TY - JOUR AN - 18014673 AU - Frost, W. H. DA - Aug ET - 08/01 J2 - American journal of public health and the nation's health LA - eng N1 - Frost, W H Am J Public Health Nations Health. 1937 Aug;27(8):759-66. PY - 1937 RN - fulltext fulltext_1208 SN - 0002-9572 (Print) 0002-9572 (Linking) SP - 759-66 ST - How Much Control of Tuberculosis? T2 - Am J Public Health Nations Health TI - How Much Control of Tuberculosis? UR - http://www.ncbi.nlm.nih.gov/pubmed/18014673http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1563282/pdf/amjphnation01049-0029.pdf VL - 27 ID - 2262 ER - TY - JOUR AN - 13458543 AU - Feldmann, F. M. DA - Oct ET - 10/01 J2 - American journal of public health and the nation's health LA - eng N1 - FELDMANN, F M Not Available Am J Public Health Nations Health. 1957 Oct;47(10):1235-41. PY - 1957 RN - fulltext fulltext_1208 SN - 0002-9572 (Print) 0002-9572 (Linking) SP - 1235-41 ST - How much control of tuberculosis: 1937-1957-1977 T2 - Am J Public Health Nations Health TI - How much control of tuberculosis: 1937-1957-1977 UR - http://www.ncbi.nlm.nih.gov/pubmed/13458543http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1551316/pdf/amjphnation01093-0004.pdf VL - 47 ID - 2263 ER - TY - JOUR AB - The second report of the Medical Research Council trial of tuberculosis vaccines in adolescents (Medical Research Council, 1959) contained an estimate of the benefit to be expected from BCG vaccination. If all those tuberculin-negative on entry to the trial in 1950–52, at the age of 14 years, had been vaccinated with BCG, the reduction in the incidence of tuberculosis in the ensuing five years would have been 59 per cent.The present study, by taking into account the recent decrease in risk of exposure to tuberculous infection in England and Wales, provides similar estimates of the scope for BCG vaccination, which are more up to date and also applicable to the whole country.Of the tuberculosis notifications among those aged 15–19 years in England and Wales in 1958, it is estimated that 52 per cent could have been prevented by BCG vaccination at the age of 14 years of all who were then tuberculin-negative. This estimate for 1958 is compared with that for 1953, which was 60 per cent. There has thus been a moderate decline in the scope for BCG vaccination during these five years. If the trend in exposure to tuberculous infection continues, BCG vaccination of all tuberculin-negative children who are aged 14 years now (1959) would apparently reduce the incidence when they become 15–19 years of age by rather less than half.In terms of the numbers of cases preventable by BCG vaccination of children aged 14 years, the scope has declined very considerably, from about 2,950 notifications among those aged 15–19 years in 1953, to 1,400 in the same age group in 1958. We may in a few years reach a situation in this country in which mass vaccination of older school children prevents only small numbers of cases of tuberculosis in adolescents. If, however, the protection from vaccination is maintained, cases will also be prevented in those aged 20 years and over.It is estimated that the official scheme for BCG vaccination at the age of 13 years, which started at the end of 1953, reduced the numbers of notifications at ages 15–19 years in England and Wales by 50 in 1956, 156 in 1957 and 241 in 1958. These small numbers are due to incomplete coverage of the 15–19 year age group in these years and the slow development of the scheme.It is suggested that a central bureau should be established to collect and interpret the information in connexion with the official vaccination scheme. This could make a valuable contribution to the eradication of tuberculosis from this country. AU - Sutherland, I. PY - 1959 RN - fulltext fulltext_1208 SP - 413-24 ST - An estimation of the scope for BCG vaccination in preventing tuberculosis among those aged 15–19 years in England and Wales at the present time T2 - Tubercle TI - An estimation of the scope for BCG vaccination in preventing tuberculosis among those aged 15–19 years in England and Wales at the present time UR - http://www.sciencedirect.com/science/article/pii/S0041387959800969 VL - 40 ID - 2264 ER - TY - JOUR AN - 14004185 AU - Waaler, H. AU - Geser, A. AU - Andersen, S. DA - Jun ET - 06/01 J2 - American journal of public health and the nation's health LA - eng N1 - WAALER, H GESER, A ANDERSEN, S Not Available Am J Public Health Nations Health. 1962 Jun;52:1002-13. PY - 1962 RN - fulltext fulltext_1208 SN - 0002-9572 (Print) 0002-9572 (Linking) SP - 1002-13 ST - The use of mathematical models in the study of the epidemiology of tuberculosis T2 - Am J Public Health Nations Health TI - The use of mathematical models in the study of the epidemiology of tuberculosis UR - http://www.ncbi.nlm.nih.gov/pubmed/14004185http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1523050/pdf/amjphnation00492-0106.pdf VL - 52 ID - 2265 ER - TY - JOUR AU - Subramaniam, M. DA - 1965 J2 - Ind.J.Tub. KW - Asia epidemiology India infection interpretation models prevalence risk of infection tuberculin tuberculin testing tuberculosis Tumkur LB - 7006 N1 - TY - JOUR TB Transmission, pathogenesis, and epidemiology Infection with tubercle bacilli Descript epi: infection TBN testing - interpretation PY - 1965 RN - fulltext fulltext_1208 SP - 101-110 ST - Mathematical approach to the study of tuberculin sensitivity T2 - Indian J Tuberc TI - Mathematical approach to the study of tuberculin sensitivity VL - 12 ID - 2266 ER - TY - JOUR AN - 6018702 AU - Brogger, S. DA - Mar ET - 03/01 J2 - The American review of respiratory disease KW - Adolescent Adult Aged BCG Vaccine Child Child, Preschool Evaluation Studies as Topic Female Humans Infant Infant, Newborn Male Middle Aged Models, Theoretical *Systems Analysis Thailand Tuberculosis/*prevention & control LA - eng N1 - Brogger, S Am Rev Respir Dis. 1967 Mar;95(3):419-34. PY - 1967 RN - fulltext fulltext_1208 SN - 0003-0805 (Print) 0003-0805 (Linking) SP - 419-34 ST - Systems analysis in tuberculosis control: a model T2 - Am Rev Respir Dis TI - Systems analysis in tuberculosis control: a model UR - http://www.ncbi.nlm.nih.gov/pubmed/6018702 VL - 95 ID - 2267 ER - TY - JOUR AN - 14754 AU - Ferebee, S. H. KW - Americas epidemiology infection models morbidity mortality tuberculosis USA N1 - IN FILE TB Transmission, pathogenesis, and epidemiology Infection with tubercle bacilli Predict epi of morbidity: prospects for the epidemic PY - 1967 RN - fulltext fulltext_1208 SP - 4-7 ST - An epidemiological model of tuberculosis in the United States T2 - Nat.Tuberc.Assoc.Bull. TI - An epidemiological model of tuberculosis in the United States UR - file://C:\literature_pdf\rm14754.pdf VL - 53 ID - 2268 ER - TY - JOUR AN - 5582655 AU - Juchniewicz, M. AU - Olakowski, T. AU - Mardon, K. ET - 01/01 KW - *Epidemiologic Methods Humans Models, Theoretical Poland Prognosis Retrospective Studies Tuberculosis/*prevention & control LA - pol N1 - Juchniewicz, M Olakowski, T Mardon, K Poland Gruzlica i choroby pluc; tuberculosis et pneumonologia Gruzlica. 1967;35(10):961-7. OP - Prognozowanie sytuacji epidemiologicznej gruzlicy na podstawie modelu epidemiometrycznego. (Doniesienie wstepne) PY - 1967 RN - fulltext fulltext_1208 SN - 0017-4955 (Print) 0017-4955 (Linking) SP - 961-967 ST - [Prognostication of the epidemiological situation of tuberculosis, based on an epidemiological model (Preliminary report)] T2 - Gruzlica i Choroby Pluc TI - [Prognostication of the epidemiological situation of tuberculosis, based on an epidemiological model (Preliminary report)] UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=5582655 VL - 35 ID - 2269 ER - TY - JOUR AB - The regional management of tuberculosis in developing nations is studied utilizing the tools of systems analysis. A tuberculosis system is visualized, the system being made up of components which are the epidemiological categories that characterize the disease. The interaction of these components determines the future state of the disease. Controls in the form of therapy, vaccinations, or prophylaxis may be superimposed on the natural processes, thus altering the future course of the disease. A descriptive mathematical model describing the flows between the various categories can be used to predict the trends both with and without intervention. An optimization model is derived from the descriptive model under the assumption that a program of reproduction of active cases has been specified. The optimization model would be used to select the forms of control which achieve the specified reduction program at least cost. Optimization is accomplished via linear programming. AN - 6059199 AU - ReVelle, C. S. AU - Lynn, W. R. AU - Feldmann, F. DA - Nov DP - Nlm ET - 11/01 KW - International Cooperation Models, Theoretical Systems Analysis Tuberculosis, Pulmonary/ prevention & control LA - eng N1 - ReVelle, C S Lynn, W R Feldmann, F United states The American review of respiratory disease Am Rev Respir Dis. 1967 Nov;96(5):893-909. PY - 1967 RN - fulltext fulltext_1208 SN - 0003-0805 (Print) 0003-0805 (Linking) SP - 893-909 ST - Mathematical models for the economic allocation of tuberculosis control activities in developing nations T2 - Am Rev Respir Dis TI - Mathematical models for the economic allocation of tuberculosis control activities in developing nations VL - 96 ID - 2270 ER - TY - JOUR AN - 5710260 AU - Waaler, H. T. DA - Dec ET - 12/01 J2 - Bulletin of the International Union against Tuberculosis KW - Adolescent Adult Aged *BCG Vaccine Child Child, Preschool *Costs and Cost Analysis Female Humans Infant Infant, Newborn Male Middle Aged Models, Theoretical Norway Operations Research Tuberculosis/prevention & control United States LA - eng N1 - Waaler, H T FRANCE Bull Int Union Tuberc. 1968 Dec;41:42-52. PY - 1968 RN - fulltext fulltext_1208 SN - 0074-9249 (Print) 0074-9249 (Linking) SP - 42-52 ST - Cost-benefit analysis of BCG-vaccination under various epidemiological situations T2 - Bull Int Union Tuberc TI - Cost-benefit analysis of BCG-vaccination under various epidemiological situations UR - http://www.ncbi.nlm.nih.gov/pubmed/5710260 VL - 41 ID - 2271 ER - TY - JOUR AU - Waaler, H. T. DO - WHO/TB/Techn.Information/67.54 KW - epidemiology fatality infection models morbidity tuberculosis LB - 4826 N1 - TY - JOUR TB Transmission, pathogenesis, and epidemiology Tuberculosis Predict epi of morbidity: prospects for the epidemic PY - 1968 RN - fulltext fulltext_1208 SP - 591-600 ST - A dynamic model for the epidemiology of tuberculosis T2 - American Review of Respiratory Disease TI - A dynamic model for the epidemiology of tuberculosis UR - Printout in Models Box 1 (In EndNote no PDF) VL - 98 ID - 2272 ER - TY - BILL AN - 4904991 DA - Jan 1 KW - Diagnosis: Computer-Assisted Tuberculosis: Pulmonary Methods Humans Models: Theoretical Statistics as Topic LB - p31852 M1 - 11 PY - 1969 RN - fulltext fulltext_1208 SP - 59-64 ST - [A statistical model for evaluating the activity of minor forms of pulmonary tuberculosis] T2 - Probl Tuberk TI - [A statistical model for evaluating the activity of minor forms of pulmonary tuberculosis] UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=4904991 VL - 47 ID - 2273 ER - TY - JOUR AB - The problems of management of tuberculosis in developing nations are studied utilizing the tools of systems analysis. The tuberculosis system consists of interacting components which are the “states of nature” of the disease. The interaction of these components determine the future state of the disease. Controls in the form of therapy, vaccinations or prophylaxis may be superimposed on the natural processes, thus altering the future course of the disease. A descriptive mathematical model describing the flows between the various categories is used to predict the trends both with and without intervention. An optimization model is derived from the descriptive model under the assumption that a program of reduction of active cases has been specified. The optimization model selects the forms of control which achieve the specified reduction program at least cost. Optimization is accomplished via linear programming. The model is general in that the parameters, costs and initial conditions may be varied for different situations. The descriptive mathematical model and the optimization model which determines the most efficient controls are intended to improve decision-making in public health management of tuberculosis. AU - Reveller, Charles AU - Lynn, Walter AU - Feldmann, Floyd DO - 10.1287/mnsc.16.4.B190 IS - 4 PY - 1969 SP - B-190-B-211 ST - An Optimization Model of Tuberculosis Epidemiology T2 - Management Science TI - An Optimization Model of Tuberculosis Epidemiology UR - http://pubsonline.informs.org/doi/abs/10.1287/mnsc.16.4.B190 VL - 16 ID - 4829 ER - TY - JOUR AU - Styblo, K. AU - Meijer, J. AU - Sutherland, I. DA - 1969 J2 - Bull.Int.Union Tuberc. KW - epidemiology models Netherlands population research risk of infection surveillance transmission tubercle tuberculosis LB - 302 N1 - TY - JOUR TB Transmission, pathogenesis, and epidemiology Infection with tubercle bacilli Etiol epi: risk of infection Risk of infection - models L1 - file://C:\literature_pdf\rm00302.pdf PY - 1969 RN - fulltext fulltext_1208 RP - IN FILE SP - 1-104 ST - The transmission of tubercle bacilli - its trend in a human population. Tuberculosis Surveillance Research Unit Report No. 1 TI - The transmission of tubercle bacilli - its trend in a human population. Tuberculosis Surveillance Research Unit Report No. 1 VL - 42 ID - 2274 ER - TY - JOUR AB - Given an adequate definition of the disease problem in epidemiological terms, it is possible to measure the epidemiological effectiveness of control measures in terms of problem reduction. This is to be distinguished from the clinical efficacy of the same measures. The practical difficulty in assessing the epidemiological effectiveness of control measures experimentally can be overcome by the construction of simulation models and the use of computers, whereby the problem reduction associated with various control strategies can be estimated numerically.By varying the levels of certain parameters of the model systematically, the sensitivity of the effectiveness of control measures to the epidemiological, operational, clinical and social parameters of a situation can be assessed. A series of articles analysing this relationship is under preparation. This first article analyses the sensitivity of the effectiveness of BCG vaccination and of the chemotherapy of tuberculosis to changes in the coverage of the eligible population groups. A previously formulated postulate stating that the marginal effectiveness of these measures decreases as their coverage increases is validated by this first series of simulations. The significance of this finding for planning national tuberculosis control strategies is discussed, as well as possible bias in the method applied. AN - 5309169 AU - Waaler, H. T. AU - Piot, M. A. ET - 01/01 J2 - Bulletin of the World Health Organization KW - Adolescent Adult Aged Antitubercular Agents/therapeutic use BCG Vaccine Child Child, Preschool Computers Epidemiologic Methods Humans Infant Infant, Newborn Middle Aged *Models, Theoretical Population Tuberculosis/*prevention & control LA - eng N1 - Waaler, H T Piot, M A SWITZERLAND Bull World Health Organ. 1969;41(1):75-93. PY - 1969 RN - fulltext fulltext_1208 SN - 0042-9686 (Print) 0042-9686 (Linking) SP - 75-93 ST - The use of an epidemiological model for estimating the effectiveness of tuberculosis control measures. Sensitivity of the effectiveness of tuberculosis control measures to the coverage of the population T2 - Bull World Health Organ TI - The use of an epidemiological model for estimating the effectiveness of tuberculosis control measures. Sensitivity of the effectiveness of tuberculosis control measures to the coverage of the population UR - http://www.ncbi.nlm.nih.gov/pubmed/5309169http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2427408/pdf/bullwho00218-0087.pdf VL - 41 ID - 2275 ER - TY - JOUR AN - 4915929 AU - Revelle, C. AU - Male, J. DA - Sep DP - Nlm ET - 09/01 KW - Costs and Cost Analysis Histological Techniques Humans Models, Theoretical Sputum/microbiology Tuberculin Test Tuberculosis/diagnosis/ prevention & control/radiography LA - eng N1 - Revelle, C Male, J United states The American review of respiratory disease Am Rev Respir Dis. 1970 Sep;102(3):403-11. PY - 1970 RN - fulltext fulltext_1208 SN - 0003-0805 (Print) 0003-0805 (Linking) SP - 403-11 ST - A mathematical model for determining case finding and treatment activities in tuberculosis control programs T2 - Am Rev Respir Dis TI - A mathematical model for determining case finding and treatment activities in tuberculosis control programs VL - 102 ID - 2276 ER - TY - JOUR AN - 5425564 AU - Waaler, H. T. DA - Jun DP - Nlm ET - 06/01 KW - Health Planning Humans Mathematics Models, Theoretical Tuberculosis, Pulmonary/epidemiology/ prevention & control LA - eng N1 - Waaler, H T France Bulletin of the International Union against Tuberculosis Bull Int Union Tuberc. 1970 Jun;43:337-44. PY - 1970 RN - fulltext fulltext_1208 SN - 0074-9249 (Print) 0074-9249 (Linking) SP - 337-44 ST - Model simulation and decision-making in tuberculosis programmes T2 - Bull Int Union Tuberc TI - Model simulation and decision-making in tuberculosis programmes VL - 43 ID - 2277 ER - TY - JOUR AB - Different combinations of coverage levels of BCG vaccination and of case-finding and treatment may achieve the same problem reduction in epidemiological terms. But the same problem reduction, in man-years of tuberculosis, may be valued differently in social terms.A social-time-preference parameter, of the form 1/(1+r)(t), is relevant to this evaluation and the level of r is critical for policy decision. The present paper studies the sensitivity of the effectiveness of BCG vaccination and of case-finding and treatment to the level of r, and the epidemiological mechanism underlying such sensitivity. A high value of r can be visualized as corresponding to a close planning horizon, a lower value of r to a more distant one. At any level of epidemiological effectiveness, a planner with a high value of r would favour case-finding and treatment, and a planner with a low value of r would tend to emphasize BCG vaccination. This influence of the social-time-preference parameter on the planner's decision is found to depend on the discounting effect of the parameter on the one hand, and on the different age- and time-patterns of the preventive effect of the major control measures, on the other. AN - 5312319 AU - Waaler, H. T. AU - Piot, M. A. DP - Nlm ET - 01/01 KW - Adolescent Adult Age Factors Aged BCG Vaccine Child Child, Preschool Humans Mathematics Middle Aged Models, Theoretical Time Factors Tuberculosis/ prevention & control LA - eng N1 - Waaler, H T Piot, M A Switzerland Bulletin of the World Health Organization Bull World Health Organ. 1970;43(1):1-16. PY - 1970 RN - fulltext fulltext_1208 SN - 0042-9686 (Print) 0042-9686 (Linking) SP - 1-16 ST - Use of an epidemiological model for estimating the effectiveness of tuberculosis control measures. Sensitivity of the effectiveness of tuberculosis control measures to the social time preference T2 - Bull World Health Organ TI - Use of an epidemiological model for estimating the effectiveness of tuberculosis control measures. Sensitivity of the effectiveness of tuberculosis control measures to the social time preference VL - 43 ID - 2278 ER - TY - JOUR AU - Chorba, R. W. AU - Sanders, J. L. PY - 1971 RN - fulltext fulltext_1208 SP - 144 ST - Planning models for tuberculosis control programs T2 - Health Services Research TI - Planning models for tuberculosis control programs UR - http://pubmedcentralcanada.ca/picrender.cgi?accid=PMC1067333&blobtype=pdf VL - 6 ID - 2279 ER - TY - JOUR AN - 5572852 AU - Endo, S. AU - Aoki, K. DA - Apr KW - Adolescent Adult Age Factors Aged BCG Vaccine Child Child, Preschool Epidemiologic Methods Humans Infant Infant, Newborn Japan Middle Aged Models, Theoretical *Systems Analysis Tuberculosis/*epidemiology/*prevention & control LA - jpn N1 - Journal Article Japan [Tuberculosis] PY - 1971 RN - fulltext fulltext_1208 SN - 0022-9776 (Print) SP - 99-111 ST - [Estimation of future epidemiological trends of tuberculosis in Japan and the evaluation of tuberculosis control programmes by simulation analysis] T2 - Kekkaku TI - [Estimation of future epidemiological trends of tuberculosis in Japan and the evaluation of tuberculosis control programmes by simulation analysis] UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=5572852 VL - 46 ID - 2280 ER - TY - JOUR AU - Sutherland, I. DA - 1971 J2 - Bull.Int.Union Tuberc. KW - epidemiology infection models research reversion risk of infection surveillance tuberculin tuberculosis LB - 4516 N1 - TY - JOUR TB Transmission, pathogenesis, and epidemiology Infection with tubercle bacilli Predict epi: risk of infection Risk of infection - models L1 - file://C:\literature_pdf\rm04516.pdf PY - 1971 RN - fulltext fulltext_1208 RP - IN FILE SP - 115-118 ST - The effect of tuberculin reversion upon the estimate of the annual risk of tuberculous infection. Tuberculosis Surveillance Research Unit Report No. 2 TI - The effect of tuberculin reversion upon the estimate of the annual risk of tuberculous infection. Tuberculosis Surveillance Research Unit Report No. 2 VL - 45 ID - 2281 ER - TY - BILL AN - 5086128 DA - Aug 11 KW - Partial Pressure Tuberculosis: Pulmonary Pulmonary Circulation Pulmonary Alveoli Humans Mathematics Models: Biological Oxygen Inhalation Therapy LB - p31846 M1 - 5 PY - 1972 RN - fulltext fulltext_1208 SP - 1237-9 ST - [Mathematical model of pulmonary tuberculosis and its treatment by lowering the partial pressure of oxygen] T2 - Dokl Akad Nauk SSSR TI - [Mathematical model of pulmonary tuberculosis and its treatment by lowering the partial pressure of oxygen] UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=5086128 VL - 205 ID - 2283 ER - TY - JOUR AN - 5077111 AU - Canetti, G. AU - Sutherland, I. AU - Svandova, E. DA - Feb 1 KW - Remission: Spontaneous Immunity France Adult Adolescent Drug Resistance: Microbial Middle Aged Epidemiologic Methods Tuberculosis: Pulmonary Netherlands Tuberculin Test Humans Great Britain Male Health Surveys Czechoslovakia Disease Outbreaks Female Mycobacterium Infections Age Factors Aged LB - p14661 PY - 1972 RN - fulltext fulltext_1208 SP - 116-34 ST - Endogenous reactivation and exogenous reinfection: their relative importance with regard to the development of non-primary tuberculosis T2 - Bull Int Union Tuberc TI - Endogenous reactivation and exogenous reinfection: their relative importance with regard to the development of non-primary tuberculosis UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=Retrieve&list_uids=5077111&dopt=abstractplus VL - 47 ID - 2282 ER - TY - BILL AN - 4775093 DA - Jan 1 KW - Costs and Cost Analysis Age Factors BCG Vaccine Humans Mathematics Tuberculosis Probability Models: Theoretical Statistics as Topic Epidemiologic Methods Socioeconomic Factors LB - p31839 M1 - 6 PY - 1973 RN - fulltext fulltext_1208 SP - 561-84 ST - [Mathematical model in tuberculosis] T2 - Ftiziologia TI - [Mathematical model in tuberculosis] UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=4775093 VL - 22 ID - 2284 ER - TY - JOUR AU - Horwitz, O. DA - 1973 J2 - Am.J.Epidemiol. KW - clinical epidemiology infection models morbidity mortality tuberculosis LB - 1172 N1 - TY - JOUR TB Transmission, pathogenesis, and epidemiology Tuberculosis Predict epi of morbidity:prospects for the epidemic PY - 1973 RN - fulltext fulltext_1208 RP - IN FILE SP - 148-159 ST - Disease, cure, and death: epidemiologic and clinical parameters for chronic diseases illustrated by a model - tuberculosis TI - Disease, cure, and death: epidemiologic and clinical parameters for chronic diseases illustrated by a model - tuberculosis VL - 97 ID - 2285 ER - TY - JOUR AU - Lotte, A. AU - Uzan, J. DA - 1973 J2 - Int.J.Epidemiol. KW - epidemiology France infection models risk of infection tuberculosis LB - 293 N1 - TY - JOUR TB Transmission, pathogenesis, and epidemiology Infection with tubercle bacilli Predict epi: risk of infection Risk of infection - models PY - 1973 RN - fulltext fulltext_1208 SP - 265-282 ST - Evolution of the rates of tuberculous infection in France and calculation of the annual risk by means of a mathematical model T2 - Int J Epidemiol TI - Evolution of the rates of tuberculous infection in France and calculation of the annual risk by means of a mathematical model VL - 2 ID - 2286 ER - TY - JOUR AB - Owing to the wide range of tuberculo statics, the treatment of tuberculosis is characerized by the possibility of applying a series of therapeutical schemes or variants"with adifferent clinical and epidemiologic efficiency in terms of ?he association of the drugs, their administration, dose, duration, etc. Epidemiologic Simplies thf preventive effect of chemotherapy in a community, overa^WenPeriod ^ ^ ^ optimization nodel 0f chemotherapy applied as acontrol.measure withinalimited area to chronic and hyperchronic patien^^^^^^ ^^^ health benefit of the population within the respective area. AN - 4775094 AU - Rusu, G. DA - Jan 1 KW - Mathematics Age Factors Humans Tuberculosis Probability Models: Theoretical Epidemiologic Methods Socioeconomic Factors LB - p31840 PY - 1973 RN - fulltext fulltext_1208 SP - 585-92 ST - [A Markovian model in tuberculosis epidemiology] T2 - Ftiziologia TI - [A Markovian model in tuberculosis epidemiology] UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=4775094 VL - 22 ID - 2287 ER - TY - JOUR AN - 9595 AU - de Ville de Goyet, C. KW - Africa AFRO epidemiology infection models risk of infection South Africa Transkei tuberculin tuberculosis N1 - IN FILE TB Transmission, pathogenesis, and epidemiology Tuberculosis Descript epi: morbidity Africa - South Africa PY - 1974 RN - fulltext fulltext_1208 SP - 957-960 ST - Annual risk of tuberculosis infection in the Transkei. Problems connected with its estimation from the data of a tuberculin survey T2 - S.Afr.Med.J. TI - Annual risk of tuberculosis infection in the Transkei. Problems connected with its estimation from the data of a tuberculin survey UR - file://C:\literature_pdf\rm09596.pdf VL - 48 ID - 2288 ER - TY - JOUR AN - 4467941 AU - Waaler, H. AU - Rouillon, A. ET - 01/01 J2 - Bulletin of the International Union against Tuberculosis KW - Adolescent *BCG Vaccine Costs and Cost Analysis Health Planning Humans Infant Models, Theoretical Psychology Time Factors Tuberculosis/*epidemiology LA - fre N1 - Waaler, H Rouillon, A FRANCE Bull Int Union Tuberc. 1974;49(1):181-206. OP - Politiques de vaccination BCG en fonction de la situation epidemiologique PY - 1974 RN - fulltext fulltext_1208 SN - 0074-9249 (Print) 0074-9249 (Linking) SP - 181-206 ST - [BCG vaccination policies as a function of the epidemiological situation] T2 - Bull Int Union Tuberc TI - [BCG vaccination policies as a function of the epidemiological situation] UR - http://www.ncbi.nlm.nih.gov/pubmed/4467941 VL - 49 ID - 2289 ER - TY - JOUR AB - Data on the dynamics of the tuberculosis situation in rural South India, obtained by the National Tuberculosis Institute, Bangalore, were fed into a mathematical model. By this means predictions about the future tuberculosis situation have been made under a wide range of hypothetical assumptions. AN - 4549350 AU - Waaler, H. T. AU - Gothi, G. D. AU - Baily, G. V. AU - Nair, S. S. ET - 01/01 J2 - Bulletin of the World Health Organization KW - Adolescent Adult Aged Antitubercular Agents/*administration & dosage/standards BCG Vaccine Child Child, Preschool Computers Demography Female Fertility Forecasting Humans India Infant Longitudinal Studies Male Middle Aged Models, Theoretical Rural Health Rural Population Tuberculosis/*epidemiology/prevention & control LA - eng M3 - Research Support, U.S. Gov't, Non-P.H.S. N1 - Waaler, H T Gothi, G D Baily, G V Nair, S S SWITZERLAND Bull World Health Organ. 1974;51(3):263-71. PY - 1974 RN - fulltext fulltext_1208 SN - 0042-9686 (Print) 0042-9686 (Linking) SP - 263-71 ST - Tuberculosis in rural South India. A study of possible trends and the potential impact of antituberculosis programmes T2 - Bull World Health Organ TI - Tuberculosis in rural South India. A study of possible trends and the potential impact of antituberculosis programmes UR - http://www.ncbi.nlm.nih.gov/pubmed/4549350http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2366280/pdf/bullwho00469-0048.pdf VL - 51 ID - 2290 ER - TY - JOUR AB - A large-scale computer service is not always available in many countries with tuberculosis problems needing epidemiological analysis. To facilitate work in such countries, a simple epidemiological model was made to calculate annual trends in the prevalence and incidence of tuberculosis and its infection, in tuberculosis mortality, and in BCG coverage, using average parameter values not specific for age groups or birth year cohorts. To test its approximation capabilities and limits, the model was applied to epidemiological data from Japan, where sufficient information was available from repeated nation-wide sample surveys and national statistics. The approximation was found to be satisfactory within certain limits. The model is best used with a desk-top computer, but the calculations can be performed with a small calculator or even by hand. AN - 1084802 AU - Azuma, Y. ET - 01/01 J2 - Bulletin of the World Health Organization KW - BCG Vaccine Epidemiologic Methods Humans Japan *Models, Theoretical Tuberculosis/*epidemiology/mortality/prevention & control LA - eng N1 - Azuma, Y SWITZERLAND Bull World Health Organ. 1975;52(3):313-22. PY - 1975 RN - fulltext fulltext_1208 SN - 0042-9686 (Print) 0042-9686 (Linking) SP - 313-22 ST - A simple simulation model of tuberculosis epidemiology for use without large-scale computers T2 - Bull World Health Organ TI - A simple simulation model of tuberculosis epidemiology for use without large-scale computers UR - http://www.ncbi.nlm.nih.gov/pubmed/1084802http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2366382/pdf/bullwho00465-0076.pdf VL - 52 ID - 2291 ER - TY - JOUR AN - 1185919 AU - Azuma, Y. DA - Jul ET - 07/01 J2 - Kekkaku : [Tuberculosis] KW - Adolescent Adult Child Child, Preschool Humans Infant Infant, Newborn Japan Middle Aged *Models, Theoretical Tuberculosis, Pulmonary/*epidemiology LA - jpn N1 - Azuma, Y JAPAN Kekkaku. 1975 Jul;50(7):199-207. PY - 1975 RN - fulltext fulltext_1208 SN - 0022-9776 (Print) 0022-9776 (Linking) SP - 199-207 ST - [Estimation of the epidemiological time trend of tuberculosis in Japan, a trial with a simple epidemiological simulation model (author's transl)] T2 - Kekkaku TI - [Estimation of the epidemiological time trend of tuberculosis in Japan, a trial with a simple epidemiological simulation model (author's transl)] UR - http://www.ncbi.nlm.nih.gov/pubmed/1185919 VL - 50 ID - 2292 ER - TY - JOUR AB - The prevalence of tuberculous infection in a population is generally estimated from calculating the proportion of tested individuals who react with at least 10 mm of induration to 5 TU of PPD-S tuberculin. Reactions due to infection with atypical mycobacteria, however, may cause the prevalence to be overestimated. This paper is concerned with an alternative method of estimating the prevalence of infection with Mycobacterium tuberculosis. The method utilizes population distributions of reaction size by dividing study populations into two groups--individuals with and without known exposure to tuberculosis. The mathematical model developed here removes the effect of atypical infections and provides a truer picture of tuberculous infection. Data from a Navy recruit population demonstrate the use of the model with the result that among recruits with no known exposure to tuberculosis, the estimated prevalence is reduced by about one-half. Among recuits with known exposure to tuberculosis, there is essentially no difference between the two methods. Important advantages in using this method are that probabilities of true infection by induration size are generated, and that itis less sensitive to variations caused by differences in reading techniques and in tuberculin potencies. Furthermore, it is applicable to other diseases if the underlying assumptions are met. AN - 1124761 AU - Rust, P. AU - Thomas, J. DA - Apr DP - Nlm ET - 04/01 KW - Epidemiologic Methods Humans Male Mathematics Models, Theoretical Naval Medicine Probability Tuberculin Test Tuberculosis, Pulmonary/ epidemiology United States LA - eng N1 - Rust, P Thomas, J United states American journal of epidemiology Am J Epidemiol. 1975 Apr;101(4):311-22. PY - 1975 RN - fulltext fulltext_1208 SN - 0002-9262 (Print) 0002-9262 (Linking) SP - 311-22 ST - A method for estimating the prevalence of tuberculosis infection T2 - Am J Epidemiol TI - A method for estimating the prevalence of tuberculosis infection UR - http://aje.oxfordjournals.org.ez.lshtm.ac.uk/content/101/4/311.full.pdf VL - 101 ID - 2293 ER - TY - JOUR AU - Sutherland, I. AU - Fayers, P. M. DA - 1975 J2 - Bull.Int.Union Tuberc. KW - age infection models risk of infection tuberculosis LB - 4519 N1 - TY - JOUR TB Transmission, pathogenesis, and epidemiology Infection with tubercle bacilli Predict epi: risk of infection Risk of infection - models L1 - file://C:\literature_pdf\rm04519.pdf PY - 1975 RN - fulltext fulltext_1208 RP - IN FILE SP - 70-81 ST - The association of the risk of tuberculous infection with age T2 - Bull.Int.Union Tuberc. TI - The association of the risk of tuberculous infection with age VL - 50 ID - 2294 ER - TY - JOUR AU - Waaler, H. AU - Galtung, O. AU - Mordal, K. DA - 1975 J2 - Bull.Int.Union Tuberc. KW - epidemiology Europe infection models Norway research risk of infection surveillance tuberculin tuberculin testing tuberculosis LB - 4517 N1 - TY - JOUR TB Transmission, pathogenesis, and epidemiology Infection with tubercle bacilli Predict epi: risk of infection Risk of infection - models L1 - file://C:\literature_pdf\rm04517.pdf PY - 1975 RN - fulltext fulltext_1208 RP - IN FILE SP - 5-61 ST - The risk of tuberculous infection in Norway. Tuberculosis Surveillance Research Unitn Report No. 3 TI - The risk of tuberculous infection in Norway. Tuberculosis Surveillance Research Unitn Report No. 3 VL - 50 ID - 2295 ER - TY - JOUR AB - Decisions about delivery programs to improve health status are characterized by indivisibilities or "lumpiness," interdependencies between case types with varying health output, high fixed costs, administrative constraints, and qualitative quity and political considerations. The nature of the constraints and the goal of health services strongly suggest a mathematical programming model to maximize a comprehensive measure of health status. In a previously unreported development, binary integer programming can be extended to consider shared fixed costs, a widespread problem in optimizing effectiveness measures such as health status. The model proposed here applies conceptually across all target populations and health programs and could be used to optimize the output of a total health system. The effects of such optimization would be appropriately reflected in the weighted life expectancy computed as a social indicator. AN - 135728 AU - Chen, M. M. AU - Bush, J. W. DA - Sep DP - Nlm ET - 09/01 KW - Cost-Benefit Analysis Health Services Humans Mass Screening Models, Theoretical Phenylketonurias/prevention & control Systems Analysis Tuberculin Test Tuberculosis/prevention & control LA - eng N1 - Chen, M M Bush, J W United states Inquiry : a journal of medical care organization, provision and financing Inquiry. 1976 Sep;13(3):215-27. PY - 1976 RN - fulltext fulltext_1208 SN - 0046-9580 (Print) 0046-9580 (Linking) SP - 215-27 ST - Maximizing health system output with political and administrative constraints using mathematical programming T2 - Inquiry TI - Maximizing health system output with political and administrative constraints using mathematical programming VL - 13 ID - 2296 ER - TY - JOUR AN - 13026 AU - Rajalalkshmi, R. AU - Nair, S. S. KW - culture diagnosis incremental yield laboratory microscopy models specimen collection sputum tuberculosis yield N1 - TB Diagnosis of tuberculosis Laboratory diagnosis Specimen collection, transport and decontamination Specimen - collection PY - 1976 RN - fulltext fulltext_1208 SP - 118-121 ST - Estimation of number of repeat examinations required to detect all tuberculosis cases in the community T2 - Indian J.Pub.Hlth. TI - Estimation of number of repeat examinations required to detect all tuberculosis cases in the community UR - file://C:\literature_pdf\rm13026.pdf VL - 20 ID - 2297 ER - TY - JOUR AU - Sutherland, I. J2 - Advances in Tuberculosis Research KW - epidemiology models risk of infection tubercle tuberculosis LB - 296 N1 - TY - JOUR TB Transmission, pathogenesis, and epidemiology Infection with tubercle bacilli Etiol epi: risk of infection Risk of infection - models L1 - file://C:\literature_pdf\rm00296.pdf PY - 1976 RN - fulltext fulltext_1208 RP - IN FILE SP - 1-63 ST - Recent studies in the epidemiology of tuberculosis, based on the risk of being infected with tubercle bacilli T2 - Advances in Tuberculosis Research TI - Recent studies in the epidemiology of tuberculosis, based on the risk of being infected with tubercle bacilli VL - 19 ID - 2298 ER - TY - JOUR AN - 1030279 AU - Sutherland, I. AU - Svandova, E. AU - Radhakrishna, S. ET - 01/01 J2 - Bulletin of the International Union against Tuberculosis KW - Adolescent Adult Female Humans Male Middle Aged *Models, Biological Recurrence Risk *Tuberculosis, Pulmonary LA - eng N1 - Sutherland, I Svandova, E Radhakrishna, S FRANCE Bull Int Union Tuberc. 1976;51(1):171-9. PY - 1976 RN - fulltext fulltext_1208 SN - 0074-9249 (Print) 0074-9249 (Linking) SP - 171-9 ST - Alternative models for the development of tuberculosis disease following infection with tubercle bacilli T2 - Bull Int Union Tuberc TI - Alternative models for the development of tuberculosis disease following infection with tubercle bacilli UR - http://www.ncbi.nlm.nih.gov/pubmed/1030279 VL - 51 ID - 2299 ER - TY - JOUR AN - 615153 AU - Nair, S. S. DA - Jul-Sep ET - 07/01 KW - *BCG Vaccine Humans *Models, Theoretical Time Factors Tuberculosis/*prevention & control LA - eng N1 - Nair, S S Comparative Study India Indian journal of public health Indian J Public Health. 1977 Jul-Sep;21(3):111-31. PY - 1977 RN - fulltext fulltext_1208 SN - 0019-557X (Print) 0019-557X (Linking) SP - 111-131 ST - A simple model for planning and assessment of programmes for tuberculosis control T2 - Indian Journal of Public Health TI - A simple model for planning and assessment of programmes for tuberculosis control UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=615153file://C:\literature_pdf\rm00731.pdf VL - 21 ID - 2300 ER - TY - BILL AN - 752918 DA - Dec 1 KW - Costs and Cost Analysis Tuberculosis: Pulmonary Brazil Humans Mathematics Models: Theoretical Socioeconomic Factors LB - p31842 M1 - 4 PY - 1978 RN - fulltext fulltext_1208 SP - 455-70 ST - [Application of a mathematical model for choosing the best combination of instruments for the detection and treatment of pulmonary tuberculosis] T2 - Rev Saude Publica TI - [Application of a mathematical model for choosing the best combination of instruments for the detection and treatment of pulmonary tuberculosis] UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=752918 VL - 12 ID - 6484 ER - TY - JOUR AU - Stevens, R. G. AU - Lee, J. A. H. DA - 1978 J2 - Am.J.Epidemiol. KW - Americas chemotherapy cohort epidemiology models mortality tuberculosis USA LB - 1249 N1 - TY - JOUR TB Transmission, pathogenesis, and epidemiology Tuberculosis deaths Descript epi: mortality Mortality - cohort studies PY - 1978 RN - fulltext fulltext_1208 SP - 120-126 ST - Tuberculosis: generation effects and chemotherapy TI - Tuberculosis: generation effects and chemotherapy VL - 107 ID - 2302 ER - TY - JOUR AU - Sivaraman, V. AU - Umasankar, V. PY - 1979 RN - fulltext fulltext_1208 SP - 4-10 ST - A simulation model of tuberculosis epidemiology adaptability to Indian conditions T2 - Ind. J. Tub. TI - A simulation model of tuberculosis epidemiology adaptability to Indian conditions UR - Print out in Chris's box VL - 26 ID - 2303 ER - TY - JOUR AB - This study illustrates how cost-effectiveness calculations provide help in decisions involving a choice between introduction of a new diagnostic procedure or a new therapy for a particular clinical problem. This type of problem is critical for areas where financial resources are limiting. Our analysis is centered on the value of diagnosis and treatment in tuberculous meningitis (Tbm) and, because of its importance to developing countries, our epidemiologic data were derived from India. When financial costs are ignored, the introduction of second line therapy (e.g., Rifampin) leads to more cures than does the introduction of even a perfect diagnostic test. However, diagnostic tests (e.g., the Bromide partition test or possibly radioassays) markedly improve case finding and to some extent increase cure rates. All affects vary markedly with the prevalence of tuberculous meningitis in the population under study. For example, net financial savings would occur were a perfect nuclear test available and conventional therapy used at a prevalence of Tbm of 30% whereas there would be a net loss if the prevalence rose to 80%. This study underscores the need for detailed studies on the radiobromide partition test and for the development of new diagnostic tests, perhaps a radioimmunoassay of either the acid fast bacillus or of an antibody to it. AN - 6771138 AU - McNeil, B. J. AU - Thompson, M. AU - Adelstein, S. J. DA - Jun DP - Nlm ET - 06/01 J2 - European journal of nuclear medicine KW - Antitubercular Agents/administration & dosage/therapeutic use Bromine/diagnostic use Cost-Benefit Analysis Decision Theory Developing Countries Humans India Length of Stay Radioisotopes/diagnostic use Tuberculosis, Meningeal/diagnosis/drug therapy/ economics LA - eng N1 - McNeil, B J Thompson, M Adelstein, S J Research Support, U.S. Gov't, P.H.S. Germany, west Eur J Nucl Med. 1980 Jun;5(3):271-6. PY - 1980 RN - fulltext fulltext_1208 SN - 0340-6997 (Print) 0340-6997 (Linking) SP - 271-6 ST - Cost effectiveness calculations for the diagnosis and treatment of tuberculous meningitis T2 - Eur J Nucl Med TI - Cost effectiveness calculations for the diagnosis and treatment of tuberculous meningitis VL - 5 ID - 2304 ER - TY - JOUR AB - An epidemiological model was used to estimate the size of the tuberculosis problem in Singapore from 1975 to 2025. It was shown that even without any control activities after 1979 there would be a reduction of the tuberculosis indices in the country. If the present control programme was pursued unchanged, a reduction of the tuberculosis problem by 10.0% and 14.5% would be expected in 2000 and 2025 respectively. Tuberculosis would be expected to remain a major public health problem over the next fifty years. In Singapore's context increased case finding and treatment of bacteriologically positive cases of tuberculosis would be the most effective ways of further reducing the tuberculosis problem over the next fifty years. Practical methods of implementing this were suggested. Reduced BCG coverage of infants was not expected to increase the tuberculosis problem to any significant extent over this period. Treatment relapse rates were shown not to be a sensitive variable that would affect the tuberculosis problem in Singapore. AN - 7283384 AU - Goh, E. H. AU - Fam, K. L. DA - Jan IS - 1 KW - Adolescent Adult *BCG Vaccine Child Child, Preschool *Forecasting Humans Immunization Schedule Infant Infant, Newborn Models, Biological Singapore Tuberculosis/*epidemiology/prevention & control N1 - Goh, E H Fam, K L eng Singapore 1981/01/01 Ann Acad Med Singapore. 1981 Jan;10(1):40-9. PY - 1981 SN - 0304-4602 (Print) 0304-4602 (Linking) SP - 40-9 ST - A dynamic model of tuberculosis epidemiology for Singapore T2 - Ann Acad Med Singapore TI - A dynamic model of tuberculosis epidemiology for Singapore UR - https://www.ncbi.nlm.nih.gov/pubmed/7283384 VL - 10 ID - 2704 ER - TY - BILL AN - 6803059 DA - Feb 15 KW - Adult Mass Screening Middle Aged Humans Mathematics Tuberculosis Adolescent Cost-Benefit Analysis Models: Theoretical Male Female Japan LB - p31832 M1 - 2 PY - 1982 RN - fulltext fulltext_1208 SP - 47-57 ST - [Use of a mathematical model for evaluation of tuberculosis case-finding with mass miniature radiography (author's transl)] T2 - Kekkaku TI - [Use of a mathematical model for evaluation of tuberculosis case-finding with mass miniature radiography (author's transl)] UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=6803059 VL - 57 ID - 2306 ER - TY - JOUR AU - Collins, J. J. DA - 1982 KW - cohort epidemiology Europe Great Britain medical models mortality tuberculosis LB - 1253 N1 - TY - JOUR TB Transmission, pathogenesis, and epidemiology Tuberculosis deaths Descript epi: mortality Mortality - cohort studies PY - 1982 RN - fulltext fulltext_1208 SP - 409-427 ST - The contribution of medical measures to the decline of mortality from respiratory tuberculosis: an age-period-cohort model T2 - Demography TI - The contribution of medical measures to the decline of mortality from respiratory tuberculosis: an age-period-cohort model VL - 19 ID - 2305 ER - TY - JOUR AB - Information on the risk of tuberculous infection in the Netherlands has been linked with information on the incidence of tuberculosis, in an attempt to estimate the risks of developing the disease following infection or reinfection. It was postulated that: (a) those with a recent primary infection had a characteristic risk of developing progressive primary tuberculosis; (b) those with a distant (i.e. not recent) primary infection and a recent reinfection had a characteristic risk of developing exogenous tuberculosis; and (c) those with a distant primary infection but no recent reinfection had a characteristic risk of developing endogenous tuberculosis. The information on the risk of tuberculous infection was used to estimate the size of the population in each of these infection classes for different age-groups and calendar years in the Netherlands. Using multiple regression to link these population figures with the information on tuberculosis incidence in the same age group and calendar year, it was possible to estimate the above risks of developing tuberculosis. For Netherlands males aged 15-69 years during the period 1951-70 the three risks of developing pulmonary tuberculosis were estimated to be: (a) 5.06 per cent annually (for 5 years) following primary infection; (b) 1.91 per cent annually (for 5 years) following reinfection; (c) 0.0253 per cent annually, after the first 5 years following primary infection, in the absence of reinfection. The corresponding (and significantly different) estimated annual risks of development of pulmonary tuberculosis for females were 5.85, 1.10 and 0.0020 per cent respectively. From these risks, it may be estimated that the degree of protection conferred by a distant primary infection, against pulmonary tuberculosis arising from a recent reinfection, was 63 per cent for males and 81 per cent for females. The estimated relative proportions of cases of progressive primary, exogenous and endogenous tuberculosis varied considerably with age and calendar year. Progressive primary tuberculosis was dominant at the younger ages, exogenous and endogenous tuberculosis at older ages. At these older ages, the great majority of cases in the Netherlands in the early 1950s appeared to be exogenous in origin, but by 1970, with the decrease in the risk of infection, the exogenous contribution had dwindled substantially, especially among males. AN - 6763793 AU - Sutherland, I. AU - Svandova, E. AU - Radhakrishna, S. DA - Dec ET - 12/01 J2 - Tubercle KW - Adolescent Adult Age Factors Aged Epidemiologic Methods Female History, 18th Century History, 20th Century Humans Male Middle Aged *Models, Biological Netherlands Recurrence Risk Sex Factors Tuberculosis, Pulmonary/*epidemiology/etiology/history LA - eng M3 - Historical Article N1 - Sutherland, I Svandova, E Radhakrishna, S SCOTLAND Tubercle. 1982 Dec;63(4):255-68. PY - 1982 RN - fulltext fulltext_1208 SN - 0041-3879 (Print) 0041-3879 (Linking) SP - 255-68 ST - The development of clinical tuberculosis following infection with tubercle bacilli. 1. A theoretical model for the development of clinical tuberculosis following infection, linking from data on the risk of tuberculous infection and the incidence of clinical tuberculosis in the Netherlands T2 - Tubercle TI - The development of clinical tuberculosis following infection with tubercle bacilli. 1. A theoretical model for the development of clinical tuberculosis following infection, linking from data on the risk of tuberculous infection and the incidence of clinical tuberculosis in the Netherlands UR - http://www.ncbi.nlm.nih.gov/pubmed/6763793http://ac.els-cdn.com/S0041387982800135/1-s2.0-S0041387982800135-main.pdf?_tid=5a366d31da488d96f9d9423663709bf6&acdnat=1345013641_fafdd63c26ae10575d849ec75af0d748 VL - 63 ID - 2307 ER - TY - BILL AB - Simulation and predictive models of tb epidemiological trends in the Czech Socialist Republic (CSR) for the 1949-2000 period were devised taking into account several variants of tb control measures. AZUMA'S simulation model from Japan was used as the basis for the mathematical processing and adapted in different parts to satisfy the conditions prevailing in the CSR. The initial conditions and parameters to go into the equations of the model were determined or estimated from statistical data for the whole of CSR or from the results of some of the more detailed partial studies. An Olivetti P 6060 minicomputer was used for calculations. Statistical data were found in satisfactory agreement with trends estimated from model simulations. The simulation models revealed that the epidemiological trends were most influenced by the treatment, less by the BCG vaccination and the least by the active case finding. As suggested by the predictive simulations, discontinuation of the programme of tb control would result in a major deterioration of the epidemiological situation. AN - 6858243 DA - Jan 1 KW - Humans Tuberculosis: Pulmonary BCG Vaccine Mathematics Models: Theoretical Male Czechoslovakia Female LB - p31837 M1 - 2 PY - 1983 RN - fulltext fulltext_1208 SP - 148-56 ST - [Measuring the effectiveness of different variants of tuberculosis control using simulation models] T2 - Z Erkr Atmungsorgane TI - [Measuring the effectiveness of different variants of tuberculosis control using simulation models] UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=6858243 VL - 160 ID - 2308 ER - TY - JOUR AN - 2504 AU - Snider, D. E., Jr. AU - Caras, G. J. AU - Koplan, J. P. KW - cost effectiveness isoniazid preventive therapy tuberculosis N1 - IN FILE TB Intervention strategies Preventive chemotherapy No sub-heading PY - 1986 RN - fulltext fulltext_1208 SP - 1579-1583 ST - Preventive therapy with isoniazid. Cost-effectiveness of different durations of therapy T2 - JAMA TI - Preventive therapy with isoniazid. Cost-effectiveness of different durations of therapy UR - file://C:\literature_pdf\rm02504.pdf VL - 255 ID - 2309 ER - TY - JOUR AB - An analysis is carried out on pulmonary tuberculosis survey data from Taiwan and Korea. A mathematical model based on a Markov process is developed and used to estimate transition rates between various disease states, as well as certain 'infection parameters', which measure the strength of the relative contributions of different disease states and of endogenous reactivation to the incidence of tuberculosis in the population. It is found that endogenous reactivation plays a primary role in generating cases, followed by chronic sources of infection, particularly those with drug-sensitive organisms. Some recommendations are made with regard to optimizing treatment regimens. The methodology can easily be applied to other countries. AD - Department of Medicine, University of British Columbia, Vancouver, Canada. AN - 3440669 AU - Schulzer, M. AU - Enarson, D. A. AU - Grzybowski, S. AU - Hong, Y. P. AU - Kim, S. J. AU - Lin, T. P. DA - Dec DP - Nlm ET - 12/01 KW - Adult Aged Epidemiologic Methods Humans Korea Middle Aged Models, Theoretical Probability Random Allocation Recurrence Taiwan Tuberculosis, Pulmonary/classification/ epidemiology LA - eng N1 - Schulzer, M Enarson, D A Grzybowski, S Hong, Y P Kim, S J Lin, T P Research Support, Non-U.S. Gov't England International journal of epidemiology Int J Epidemiol. 1987 Dec;16(4):584-9. PY - 1987 RN - fulltext fulltext_1208 SN - 0300-5771 (Print) 0300-5771 (Linking) SP - 584-9 ST - An analysis of pulmonary tuberculosis data in Taiwan and Korea T2 - Int J Epidemiol TI - An analysis of pulmonary tuberculosis data in Taiwan and Korea UR - http://ije.oxfordjournals.org.ez.lshtm.ac.uk/content/16/4/584.full.pdf VL - 16 ID - 2310 ER - TY - JOUR AB - In this paper, a simplified model describing the stochastic process underlying the etiology of contagious and noncontagious diseases with mass screening is developed. Typical examples might include screening of tuberculosis in urban ghetto areas, venereal diseases in the sexually active, or AIDS in high risk population groups. The model is addressed to diseases which have zero or negligible latent periods. In the model, it is assumed that the reliabilities of the screening tests are constant, and independent of how long the population unit has the disease. Both tests with perfect and imperfect reliabilities are considered. It is shown that most of the results of a 1978 study by W.P. Pierskalla and J.A. Voelker for noncontagious diseases can be generalized for contagious diseases. A mathematical program for computing the optimal test choice and screening periods is presented. It is shown that the optimal screening schedule is equally spaced for tests with perfect reliability. Other properties relating to the managerial problems of screening frequencies, test selection, and resource allocation are also presented. AN - 10303164 AU - Lee, H. L. AU - Pierskalla, W. P. DA - Nov-Dec DP - Nlm ET - 10/06 KW - Communicable Diseases/ etiology/transmission Health Resources Health Services Research Mass Screening/ organization & administration Models, Statistical LA - eng N1 - Lee, H L Pierskalla, W P Research Support, U.S. Gov't, Non-P.H.S. Review United states Operations research Oper Res. 1988 Nov-Dec;36(6):917-28. PY - 1988 RN - fulltext fulltext_1208 SN - 0030-364X (Print) 0030-364X (Linking) SP - 917-28 ST - Mass screening models for contagious diseases with no latent period T2 - Oper Res TI - Mass screening models for contagious diseases with no latent period VL - 36 ID - 2311 ER - TY - JOUR AB - This study illustrates the use of disease modeling and simulation techniques to the study of the spread of disease within and between social networks. A Reed-Frost type model of disease spread is used to construct a simulation of the spread of tuberculosis within three prehistoric populations of the Lower Illinois River Valley during Middle Woodland, Late Woodland, and Mississippian times. A high and low population size was modeled for each time period. Late Woodland model 2 (low population estimate) is the only model that experienced pathogen extinction with host survival. The rest of the models experienced rapid and severe host population decline. The results of the simulation suggest that a social network size of between 180 and 440 persons is required under the conditions of this model for host-pathogen coexistence (i.e., endemicity) to occur. The severe population decline experienced by these populations suggests that tuberculosis as modeled here could not have existed in these populations. Future refinements of modeling and simulation techniques can provide additional insights into how disease spreads among social contacts. AD - Department of Anthropology, Case Western Reserve University, Cleveland, Ohio 44106. AN - 3066224 AU - McGrath, J. W. DA - Dec DO - 10.1002/ajpa.1330770409 [doi] DP - Nlm ET - 12/01 KW - History, Ancient History, Medieval Humans Illinois Models, Biological Social Environment Tuberculosis/history/ transmission LA - eng N1 - McGrath, J W Historical Article United states American journal of physical anthropology Am J Phys Anthropol. 1988 Dec;77(4):483-96. PY - 1988 RN - fulltext fulltext_1208 SN - 0002-9483 (Print) 0002-9483 (Linking) SP - 483-96 ST - Social networks of disease spread in the lower Illinois valley: a simulation approach T2 - Am J Phys Anthropol TI - Social networks of disease spread in the lower Illinois valley: a simulation approach UR - http://onlinelibrary.wiley.com/doi/10.1002/ajpa.1330770409/abstract VL - 77 ID - 2312 ER - TY - JOUR AB - Isoniazid chemoprophylaxis is not recommended for all persons infected with tubercle bacilli. Because of the small but significant risk of isoniazid hepatotoxicity, chemoprophylaxis is reserved for only those at the highest risk of tuberculosis activation. To evaluate this policy, we performed a cost-effectiveness analysis of isoniazid chemoprophylaxis for two populations with positive tuberculin skin tests: recent tuberculin converters, who are at high risk for activation, and older tuberculin reactors, who have a low risk for activation and for whom chemoprophylaxis is not now recommended. The cost-effectiveness ratios found were stable, despite wide variations in model assumptions and probability estimates. For high-risk tuberculin reactors, chemoprophylaxis resulted in net medical care monetary savings, extended life expectancy, and fewer fatal illnesses. For low-risk tuberculin reactors, chemoprophylaxis resulted in positive, but small, health effects. Because the cost to gain these positive effects were also small, the resulting cost-effectiveness ratios were reasonable and in the realm of accepted prevention strategies: $12,625 to gain one year of life and $35,011 to avert one death. These findings suggest that the current policy is too restrictive and that many in the large population of low-risk tuberculin reactors should be considered for isoniazid chemoprophylaxis. AD - Department of Community Medicine, Mount Sinai School of Medicine, New York, NY 10029. AN - 3134928 AU - Rose, D. N. AU - Schechter, C. B. AU - Fahs, M. C. AU - Silver, A. L. DA - Mar-Apr ET - 03/01 KW - Adult Age Factors Cost-Benefit Analysis Drug-Induced Liver Injury/etiology/mortality Humans Isoniazid/adverse effects/*therapeutic use Life Expectancy Male Middle Aged Risk Factors Tuberculin Test Tuberculosis/diagnosis/mortality/*prevention & control LA - eng N1 - Rose, D N Schechter, C B Fahs, M C Silver, A L United states American journal of preventive medicine Am J Prev Med. 1988 Mar-Apr;4(2):102-9. PY - 1988 RN - fulltext fulltext_1208 SN - 0749-3797 (Print) 0749-3797 (Linking) SP - 102-9 ST - Tuberculosis prevention: cost-effectiveness analysis of isoniazid chemoprophylaxis T2 - Am J Prev Med TI - Tuberculosis prevention: cost-effectiveness analysis of isoniazid chemoprophylaxis UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=3134928 VL - 4 ID - 2313 ER - TY - JOUR AB - The epidemiological model Eskimo has been utilized to simulate some epidemiological parameters relative to tuberculosis in a restricted geographical area of northern Italy. After having identified a series of features relative to the regimens applied in the area in the period 1982-86 and which were found to be compatible with the observed data, this hypothesis has been utilized to project data on tuberculosis for the period 1986-1996. The results have indicated that the incidence in the area should stabilize around values of 20 new cases per year (per 100,000 population). A decrease in the incidence can be expected to occur only if the regimens so far employed are brought to a greater part of the patients' population (increasing coverage). The effects of importing the disease from developing countries through immigration and of the AIDS epidemic are likely to negatively affect the trend of tuberculosis incidence in the future. AN - 2488908 AU - Acocella, G. AU - Comaschi, E. AU - Nonis, A. AU - Rossanigo, C. AU - Migliori, G. B. DA - Jan-Dec DP - Nlm ET - 01/01 KW - Cohort Studies Computer Simulation Emigration and Immigration Forecasting Humans Italy/epidemiology Models, Theoretical Retrospective Studies Tuberculosis/ epidemiology LA - eng N1 - Acocella, G Comaschi, E Nonis, A Rossanigo, C Migliori, G B Italy Giornale italiano di chemioterapia G Ital Chemioter. 1989 Jan-Dec;36(1-3):11-6. PY - 1989 RN - fulltext fulltext_1208 SN - 0017-0445 (Print) 0017-0445 (Linking) SP - 11-6 ST - Past, present and future trends in tuberculosis epidemiology in a region of northern Italy. An analysis carried out through the application of a simulation model (Eskimo) T2 - G Ital Chemioter TI - Past, present and future trends in tuberculosis epidemiology in a region of northern Italy. An analysis carried out through the application of a simulation model (Eskimo) VL - 36 ID - 2314 ER - TY - JOUR AB - An epidemiological model of tuberculosis, based on the natural history of tuberculosis and the control programmes in Indonesia, was constructed. This model was used for estimating future tuberculosis-prevented cases and costs for three treatment strategies--the 100% standard course, the 100% short course, and the existing strategy (a combination of 65% standard course and 35% short course)--in accordance with the master plan of the Indonesian Government's tuberculosis control programme. A cost-effectiveness analysis of the three strategies confirmed that the short-course strategy was the most cost-effective. Sensitivity analysis, which applied a broad range of parameters, continued to confirm the short-course strategy as the most cost-effective. If the short-course strategy had been applied in 1980 instead of the existing strategy (using the most likely parameters), the short-course strategy would prevent 1.8 million sputum-positive cases and would save 61.0 million dollars by the year 2000. AD - Division of Chronic Disease Control, Centers for Disease Control, Atlanta, Georgia 30333. AN - 2498217 AU - Joesoef, M. R. AU - Remington, P. L. AU - Jiptoherijanto, P. T. DA - Mar ET - 03/01 J2 - International journal of epidemiology KW - Antitubercular Agents/*administration & dosage Cost-Benefit Analysis Drug Therapy, Combination Humans Indonesia Models, Theoretical National Health Programs/*economics Sensitivity and Specificity Tuberculosis, Pulmonary/*drug therapy/economics/epidemiology LA - eng M3 - Research Support, Non-U.S. Gov't N1 - Joesoef, M R Remington, P L Jiptoherijanto, P T ENGLAND Int J Epidemiol. 1989 Mar;18(1):174-9. PY - 1989 RN - fulltext fulltext_1208 SN - 0300-5771 (Print) 0300-5771 (Linking) SP - 174-9 ST - Epidemiological model and cost-effectiveness analysis of tuberculosis treatment programmes in Indonesia T2 - Int J Epidemiol TI - Epidemiological model and cost-effectiveness analysis of tuberculosis treatment programmes in Indonesia UR - http://www.ncbi.nlm.nih.gov/pubmed/2498217http://ije.oxfordjournals.org.ez.lshtm.ac.uk/content/18/1/174.full.pdf VL - 18 ID - 2315 ER - TY - JOUR AB - The role of isoniazid prophylaxis in low-risk patients with positive Mantoux skin tests has recently been questioned. In general, recent research has focused on the risk/benefit ratio. We, therefore, decided to extend these data and apply a cost-effectiveness analysis of the routine use of isoniazid prophylaxis from a societal perspective. Costs per case prevented were calculated for a 20-, 50-, and 70-yr-old low-risk patient who had a positive Mantoux test with base, high, and low costings. Rates were also calculated based on the use of direct costs alone and direct and indirect costs combined. Costs varied from Canadian $8,586.00 in a 20-yr-old patient to $40,102.00 in a 70-yr-old patient per case prevented based on direct costs with costs ranging from $3,236.00 to $11,320.00 with both direct and indirect costs included. These costs could be considered reasonable from a societal perspective but do not address the issue of any increased life expectancy resulting from chemoprophylaxis. AD - Department of Medicine, McMaster University, Hamilton, Ontario, Canada. AN - 2121080 AU - Fitzgerald, J. M. AU - Gafni, A. DA - Oct DP - Nlm ET - 10/01 J2 - The American review of respiratory disease KW - Adolescent Adult Aged Canada Child Cost-Benefit Analysis Humans Isoniazid/adverse effects/ therapeutic use Middle Aged Tuberculin Test Tuberculosis, Pulmonary/diagnosis/ economics/prevention & control LA - eng N1 - Fitzgerald, J M Gafni, A United states Am Rev Respir Dis. 1990 Oct;142(4):848-53. PY - 1990 RN - fulltext fulltext_1208 SN - 0003-0805 (Print) 0003-0805 (Linking) SP - 848-53 ST - A cost-effectiveness analysis of the routine use of isoniazid prophylaxis in patients with a positive Mantoux skin test T2 - Am Rev Respir Dis TI - A cost-effectiveness analysis of the routine use of isoniazid prophylaxis in patients with a positive Mantoux skin test VL - 142 ID - 2316 ER - TY - JOUR AB - The progression of HIV-related disease from infection to death is represented as a staged Markov model. Transitions between stages are considered reversible. The model is fitted to data from a cohort of African prostitutes by means of maximum likelihood. It appears that the progression to symptomatic disease (Centers for Disease Control stage IV) in this population is considerably more rapid than that reported from studies in Western countries. AD - Kenya Medical Research Institute, Nairobi. AN - 2175619 AU - Nagelkerke, N. J. AU - Plummer, F. A. AU - Holton, D. AU - Anzala, A. O. AU - Manji, F. AU - Ngugi, E. N. AU - Moses, S. DA - Aug DP - Nlm ET - 08/01 KW - Acquired Immunodeficiency Syndrome/classification/ epidemiology/transmission Centers for Disease Control and Prevention (U.S.) Cohort Studies Female Humans Kenya/epidemiology Markov Chains Models, Biological Prostitution Socioeconomic Factors Tanzania/ethnology United States/epidemiology individual prognoses, for developing and testing intervention strategies, for determining the reproductive rate of the disease, and for prevalence of the disease. Mathematical modeling of HIV infection in Africa is necessitated because the disease is more widespread and the immune system is constantly active due to the exposure to diseases such as malaria and tuberculosis. The Markov model for this analysis was selected because parametric estimation is not based on the time a stage is entered, but on the duration between observations and the stages at the time of observation. The HIV infected female prostitutes in the Pumwani area of Nairobi, Kenya (a population primarily of Tanzanian origin) have been identified as a study population since 1985, and seen every 6 months in clinic, or as needed. Data are constricted by the movement out of the area in the end stage of disease, which is only partially solved by tracking with community health workers. The stages identified in incubation estimation are stage 1: seropositive but symptom free (CDC stage II) stage 2: generalized lymphadenopathy (CDC stage III) stage 3: symptomatic disease (CDC stage IV) and stage 4: death. Data reflect the movement back and forth between stage 1 and 2, between 2 and 3, so the model is not a pure Longini model but rather a timed homogeneous staged model with reversible stages called transition parameters computed in a numerical differentiation. The Fortran computer program for the analyses is available from the authors. The results suggest a quick transition between seroconversion and lymphadenopathy (2.4 months) and unlikely reversal, with the mean waiting time until passage to stage 3 is approximately 2.6 years and conversions are common. Since opportunistic infections are treatable, this makes sense. Assuming a correct model, the estimation of the transition time of 20 months of h34 value of .01 and .05, the mean passage time from stage 1, 2, 3 to 4 (death) is 9.1, 8.9, and 6.2 years 12.9, 12.7, and 10.1 years respectively. The implications are that 1) when infectiousness is hypothesized to be not uniform, peak infectivity occurs earlier in Africa than in the West at least among prostitutes, or 2) if infectivity is constant throughout the incubation period, then HIV transmission must be higher in Africa to explain the high rate of infection. LA - eng N1 - Nagelkerke, N J Plummer, F A Holton, D Anzala, A O Manji, F Ngugi, E N Moses, S Research Support, Non-U.S. Gov't United states AIDS (London, England) AIDS. 1990 Aug;4(8):743-7. PY - 1990 RN - fulltext fulltext_1208 excl_noTB SN - 0269-9370 (Print) 0269-9370 (Linking) SP - 743-7 ST - Transition dynamics of HIV disease in a cohort of African prostitutes: a Markov model approach T2 - AIDS TI - Transition dynamics of HIV disease in a cohort of African prostitutes: a Markov model approach VL - 4 ID - 2317 ER - TY - JOUR AD - CASE WESTERN RESERVE UNIV,METROHLTH MED CTR,CLEVELAND,OH 44106. AN - WOS:A1991GJ22700072 AU - Suen, J. S. AU - Cebul, R. D. AU - Speroff, T. AU - Daniel, T. M. DA - Oct-Dec IS - 4 J2 - Med. Decis. Mak. KW - Health Care Sciences & Services Medical Informatics LA - English M3 - Meeting Abstract N1 - ISI Document Delivery No.: GJ227 Times Cited: 0 Cited Reference Count: 0 Suen, js cebul, rd speroff, t daniel, tm 0 Hanley & belfus inc Philadelphia PY - 1991 SN - 0272-989X SP - 331-331 ST - MODELING TUBERCULOSIS AND THE EFFECTIVENESS OF ALTERNATIVE CONTROL STRATEGIES IN AN HIV-PREVALENT POPULATION T2 - Medical Decision Making TI - MODELING TUBERCULOSIS AND THE EFFECTIVENESS OF ALTERNATIVE CONTROL STRATEGIES IN AN HIV-PREVALENT POPULATION UR - ://WOS:A1991GJ22700072 VL - 11 ID - 6399 ER - TY - JOUR AN - 12954 AU - Balasangameshwara, V. H. AU - Chakraborty, A. K. AU - Chaudhuri, K. KW - Asia case-finding epidemiology India infection interventions models morbidity mortality tuberculosis N1 - IN FILE TB Transmission, pathogenesis, and epidemiology Tuberculosis Predict epi of morbidity: prospects for the epidemic PY - 1992 RN - fulltext fulltext_1208 SP - 87-98 ST - A mathematical construct of epidemiological time trend in tuberculosis - a fifty year study T2 - Indian J.Tuberc. TI - A mathematical construct of epidemiological time trend in tuberculosis - a fifty year study UR - file://C:\literature_pdf\rm12954.pdf VL - 39 ID - 2318 ER - TY - JOUR AB - OBJECTIVE: To study the impact of the HIV epidemic on tuberculosis (TB) incidence in developing countries. DESIGN: A simple mathematical model is constructed using figures from published reports to estimate the rise of TB incidence as the HIV epidemic expands. METHOD: Two groups with different risk of developing TB are identified: individuals with dual infection of HIV and Mycobacterium tuberculosis and the rest of the population. The model is based on a combination of the incidence and the percentage of TB in these two groups. The expected rise in TB incidence and the percentage of TB cases that will be HIV-positive are plotted against the prevalence of HIV. CONCLUSIONS: Unless appropriate action is taken, TB incidence in developing countries will double as the prevalence of HIV infection reaches 13 per hundred adults. AD - Spanish Red Cross, La Paz, Bolivia. AN - 1466853 AU - Bermejo, A. AU - Veeken, H. AU - Berra, A. DA - Oct DP - Nlm ET - 10/01 KW - Cohort Studies Developing Countries Forecasting HIV Infections/complications/ epidemiology Humans Models, Theoretical Tuberculosis/complications/ epidemiology HIV infection greatly increases the risk of developing active TB among those with latent Mycobacterium tuberculosis infection. Thus researchers have used data from existing research to develop a mathematical model to gauge the increase in TB incidence in developing countries while considering rising HIV prevalence among adults. They look at 2 groups with sizable differences in risk of acquiring TB: adults with both HIV and M. tuberculosis infections and all other adults. The researchers plot the expected increase in TB incidence and percentage of TB cases that also have HIV infection against HIV prevalence. According to the model, when the prevalence of HIV infection hits 13% of adults in developing countries, the number of new TB cases doubles. Most of this increase will occur in areas that already lack diagnostic services, drugs, hospital beds, and other needed supplies. TB chemoprophylaxis treatment of HIV-positive people could result in a lower increase in TB incidence, however. WHO has set a goal of 50% reduction in LA - eng N1 - Bermejo, A Veeken, H Berra, A Comparative Study United states AIDS (London, England) AIDS. 1992 Oct;6(10):1203-6. PY - 1992 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 0269-9370 (Print) 0269-9370 (Linking) SP - 1203-6 ST - Tuberculosis incidence in developing countries with high prevalence of HIV infection T2 - AIDS TI - Tuberculosis incidence in developing countries with high prevalence of HIV infection VL - 6 ID - 2319 ER - TY - JOUR AB - Tuberculosis remains the leading cause of death in the world from a single infectious disease, although there is little knowledge of the mechanisms of its pathogenesis and protection from it. After a century of decline in the United States, tuberculosis is increasing, and strains resistant to multiple antibiotics have emerged. This excess of cases is attributable to changes in the social structure in cities, the human immunodeficiency virus epidemic, and a failure in certain major cities to improve public treatment programs. The economic costs of not adequately addressing the problem of tuberculosis in this country are estimated from an epidemiological model. AD - Howard Hughes Medical Institute, Albert Einstein College of Medicine, Bronx, NY 10461. AN - 1509256 AU - Bloom, B. R. AU - Murray, C. J. DA - Aug 21 ET - 08/21 J2 - Science KW - Acquired Immunodeficiency Syndrome/complications Animals Antibiotics, Antitubercular/pharmacology/therapeutic use Drug Resistance, Microbial History, 17th Century History, 19th Century History, 20th Century History, Ancient Humans Mycobacterium tuberculosis/drug effects Tuberculosis/complications/drug therapy/*epidemiology/transmission United States/epidemiology L1 - internal-pdf://2568331268/Bloom-1992-Tuberculosis_ commentary on a reeme.pdf LA - eng M3 - Historical Article Research Support, Non-U.S. Gov't Review N1 - Bloom, B R Murray, C J New York, N.Y. Science. 1992 Aug 21;257(5073):1055-64. PY - 1992 RN - fulltext fulltext_1208 SN - 0036-8075 (Print) 0036-8075 (Linking) SP - 1055-64 ST - Tuberculosis: commentary on a reemergent killer T2 - Science TI - Tuberculosis: commentary on a reemergent killer UR - http://www.ncbi.nlm.nih.gov/pubmed/1509256 http://science.sciencemag.org/content/sci/257/5073/1055.full.pdf VL - 257 ID - 2320 ER - TY - JOUR AB - The impact of the human immunodeficiency virus (HIV) on tuberculosis is well documented. Its effect in populations with a high proportion of dually infected individuals is likely to be significant. Sub-Saharan Africa is one such region and to better document the effect of HIV infection on tuberculosis there we developed a mathematical model to predict the likely extra numbers of tuberculosis cases due to it. A mathematical model was developed using a variety of scenarios giving a range of risks for the period 1980-2000. The four scenarios included (1) a low rate of 1% risk of tuberculosis infection in year 0 (1980) with 45% tuberculosis infection prevalence, and an HIV prevalence of 2% in 1989; (2) a 2% risk of tuberculosis infection in year 0 with 60% tuberculosis infection prevalence, and a 2% HIV prevalence in 1989; (3) a 2% risk of tuberculosis infection in year 0 with 60% tuberculosis infection prevalence, and a 10% HIV prevalence in 1989; and (4) a 2% risk of tuberculosis infection in year 0 with 60% tuberculosis infection prevalence and a 20% HIV prevalence in 1989. Under scenarios 1 and 2, a 50-60% increase in smear-positive rates in the subpopulation (15-45 years old) is predicted for the year 2000, under scenario 3, smear-positive rates in the subpopulation in the year 2000 are expected to increase four-fold from the 1980 baseline. Under scenario 4, a 10-fold increase in smear-positive rates in 2000 is expected in the subpopulation. Under this scenario, total disease will have increased 12-fold in the subpopulation.(ABSTRACT TRUNCATED AT 250 WORDS) AD - Department of Medicine, Vancouver General Hospital, British Columbia, Canada. AN - 1525378 AU - Schulzer, M. AU - Fitzgerald, J. M. AU - Enarson, D. A. AU - Grzybowski, S. DA - Feb DO - 0962-8479(92)90080-4 [pii] 10.1016/0962-8479(92)90080-4 [doi] DP - Nlm ET - 02/01 KW - Adolescent Adult Africa/epidemiology Child HIV Infections/ complications Humans Incidence Middle Aged Models, Biological Opportunistic Infections/complications/ epidemiology Prevalence Risk Factors Tuberculosis, Pulmonary/complications/ epidemiology well-documented. Its effect on populations with a high proportion of dually infected individuals is likely to be significant. Sub-Saharan Africa is one such region and in order to better document the effect of HIV infection on tuberculosis in that region, the authors developed a mathematical model to predict the likely extra numbers of tuberculosis due to it. A mathematical model was developed using a variety of scenarios which provided a range of risks for the 1980-2000 period. The 4 scenarios included: a low rate of 1% risk of tuberculosis infection in the year 0 (1980) with 45% tuberculosis infection prevalence and a HIV prevalence of 2% in 1989 a 2% risk of tuberculosis infection in year 0 with 60% tuberculosis infection prevalence and a 2% HIV prevalence in 1989 a 2% risk of tuberculosis infection in year 0 with 60% tuberculosis infection prevalence and a 10% HIV prevalence in 1989 and a 2% risk of tuberculosis infection in year 0 with 60% tuberculosis infection prevalence and a 20% HIV prevalence in 1989. In scenarios 1 and 2, a 50-60% increase in smear-positive rates in the subpopulation (ages 15-45 years old) is predicted for the year 2000 in scenario 3, smear-positive rates in the subpopulation in the year 2000 are expected to increase 4-fold from the 1980 baseline and in scenario 4, a 10-fold increase in smear-positive rates in the year 200 is expected in the subpopulation. Total disease will have increased 12-fold in the subpopulation in this scenario. These data suggest that there will be a dramatic increase in the number of tuberculosis cases due to HIV infection in sub-Saharan Africa which will likely strain the already fragile health care system in this region. (author's modified) LA - eng N1 - Schulzer, M Fitzgerald, J M Enarson, D A Grzybowski, S Scotland Tubercle and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease Tuber Lung Dis. 1992 Feb;73(1):52-8. PY - 1992 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 0962-8479 (Print) 0962-8479 (Linking) SP - 52-8 ST - An estimate of the future size of the tuberculosis problem in sub-Saharan Africa resulting from HIV infection T2 - Tuber Lung Dis TI - An estimate of the future size of the tuberculosis problem in sub-Saharan Africa resulting from HIV infection UR - http://ac.els-cdn.com/0962847992900804/1-s2.0-0962847992900804-main.pdf?_tid=cffaa2ae794e91d787e584ec38b9d418&acdnat=1345013225_6e9459f9bf03fac6da11deacd622154e VL - 73 ID - 2321 ER - TY - JOUR AB - Concerns have been raised about whether the interaction between tuberculosis and human immunodeficiency virus (HIV) may lead worldwide to a recrudescent tuberculosis pandemic. These concerns are particularly grave in Africa which has a high prevalence of both tuberculosis and HIV. This study used a computer simulation model to examine the effect of tuberculosis-HIV interactions on tuberculosis prevalence and mortality in Africa. The model then assessed the impact of expanding treatment and chemoprophylaxis programmes on tuberculosis prevalence and mortality over the next decade. In communities where 20% of the population is infected with HIV and 25% receive treatment for tuberculosis, deaths from tuberculosis would be 100% higher than in communities where none of the population is HIV-infected. In a population the size of Uganda's, during one decade there would be approximately an additional 530,000 deaths from tuberculosis. When 50% of patients with active tuberculosis receive treatment, one death will be averted for every 2.5 people who receive treatment. The prevalence of active tuberculosis could be cut by over 90% in a decade by providing effective chemoprophylaxis to 30% of individuals with inactive TB. In conclusion, TB is only one example of a preventable and treatable infectious disease which can be spread through casual contact and which, because of its higher prevalence among the HIV positive population, may lead to a preventable increase in incidence of infection among the general population. AD - Department of Health Care Policy, Harvard Medical School, Boston, MA 02115. AN - 8249065 AU - Heymann, S. J. DA - Jul-Aug DP - Nlm ET - 07/01 KW - AIDS-Related Opportunistic Infections/drug therapy/epidemiology/ prevention & control Africa/epidemiology Computer Simulation Humans Models, Biological Prevalence Tuberculosis/drug therapy/epidemiology/ prevention & control LA - eng N1 - Heymann, S J Research Support, Non-U.S. Gov't England Transactions of the Royal Society of Tropical Medicine and Hygiene Trans R Soc Trop Med Hyg. 1993 Jul-Aug;87(4):406-11. PY - 1993 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 0035-9203 (Print) 0035-9203 (Linking) SP - 406-11 ST - Modelling the efficacy of prophylactic and curative therapies for preventing the spread of tuberculosis in Africa T2 - Trans R Soc Trop Med Hyg TI - Modelling the efficacy of prophylactic and curative therapies for preventing the spread of tuberculosis in Africa UR - http://ac.els-cdn.com/003592039390014H/1-s2.0-003592039390014H-main.pdf?_tid=8ad90a4371d1c405a8a164c4f5f14d1d&acdnat=1345012470_496d33934a357930490bdffc26f770dd VL - 87 ID - 2322 ER - TY - JOUR AB - A deterministic model is proposed for the study of the dynamics of acquired immunodeficiency syndrome (AIDS) and tuberculosis (TB) co-infection. The model is comprised by a set of sixteen ordinary differential equations representing different states of both diseases, and it is intended to provide a theretical framework for the study of the interaction between both infections. Numerical simulations of the model resulted in three striking outcomes: first, the pathogenicity of Human Immunodeficiency Virus (HIV) is enhanced by the presence of TB, and vice-versa; second, the prevalence of AIDS is higher in the presence of TB; and third, relative risk analysis demonstrated a much stronger influence of AIDS on TB than the other way around. AU - Massad, Eduardo AU - Burattini, Marcelo Nascimento AU - Coutinho, Francisco Antonio Bezerra AU - Yang, Hyung Mo AU - Raimundo, Silvia Martorano DO - 10.1016/0895-7177(93)90013-O PY - 1993 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 0895-7177 SP - 7-21 ST - Modeling the interaction between aids and tuberculosis T2 - Mathematical and Computer Modelling TI - Modeling the interaction between aids and tuberculosis UR - http://www.sciencedirect.com/science/article/pii/089571779390013O VL - 17 ID - 2323 ER - TY - JOUR AB - As a result of many interacting variables, including crowded shelters and limited access to health care, homeless persons are at high risk for tuberculosis. Using traditional approaches, control of tuberculosis in this population has been difficult. Decision analysis was used to investigate the cost-effectiveness of BCG (bacillus Calmette-Guerin) vaccination in persons attending homeless shelters. This vaccination was cost-effective over a wide range of assumptions. Using conservative assumptions, a vaccine that was at least 40 percent effective would result in a net cost savings. If the efficacy of the vaccine were 50 percent, $4,000 would be saved, 12 life-years gained, and 23 cases of active tuberculosis prevented for every 1,000 persons vaccinated. Further study of the BCG vaccine in homeless persons and other populations at risk is warranted. AD - Division of General Medicine, University of Iowa College of Medicine, Iowa City. AN - 8131444 AU - Nettleman, M. D. DA - Apr DP - Nlm ET - 04/01 J2 - Chest KW - Adult BCG Vaccine/economics Cost-Benefit Analysis Decision Support Techniques Homeless Persons Humans Middle Aged Tuberculosis, Pulmonary/economics/ prevention & control United States Vaccination/economics LA - eng N1 - Nettleman, M D Research Support, Non-U.S. Gov't United states Chest. 1993 Apr;103(4):1087-90. PY - 1993 RN - fulltext fulltext_1208 SN - 0012-3692 (Print) 0012-3692 (Linking) SP - 1087-90 ST - Use of BCG vaccine in shelters for the homeless. A decision analysis T2 - Chest TI - Use of BCG vaccine in shelters for the homeless. A decision analysis VL - 103 ID - 2324 ER - TY - JOUR AB - The cost-effectiveness of chemotherapy for pulmonary sputum smear-positive tuberculosis was examined in the national tuberculosis control programmes of Malawi, Mozambique and Tanzania. In these three programmes, routine cure rates have exceeded 80 per cent. Average, average incremental and marginal unit costs for standard, short-course and retreatment regimens with and without hospitalization have been measured. The average incremental cost per year of life saved through chemotherapy ranged from US $0.90-3.10. In all conditions, short-course chemotherapy is preferable to standard 12-month chemotherapy. When hospitalization during the intensive phase of chemotherapy increases the cure rate by 10-15 percentage points, it can be relatively cost-effective. Analysing the cost-effectiveness of short-course and standard chemotherapy, where the depth of the margin of benefit is different, illustrates some of the dangers of simplistic use of cost-effectiveness ratios. AN - 10172113 AU - de Jonghe, E. AU - Murray, C. J. AU - Chum, H. J. AU - Nyangulu, D. S. AU - Salomao, A. AU - Styblo, K. DA - Apr-Jun KW - Ambulatory Care/economics Comparative Study Cost-Benefit Analysis/statistics & numerical data Data Collection Developing Countries Health Care Costs/*statistics & numerical data Hospitalization/economics Human Laboratory Techniques and Procedures/economics Malawi Mozambique National Health Programs/*economics Program Evaluation/*economics Tanzania Tuberculosis, Pulmonary/diagnosis/*drug therapy/*economics/transmission N1 - 95015805 0749-6753 Journal Article Review Review, Tutorial PY - 1994 RN - fulltext fulltext_1208 SP - 151-181 ST - Cost-effectiveness of chemotherapy for sputum smear-positive pulmonary tuberculosis in Malawi, Mozambique and Tanzania T2 - International Journal of Health Planning and Management TI - Cost-effectiveness of chemotherapy for sputum smear-positive pulmonary tuberculosis in Malawi, Mozambique and Tanzania UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=10172113 VL - 9 ID - 2325 ER - TY - JOUR AB - Forecasts of tuberculosis morbidity and mortality are presented for the decade 1990-99. An estimated 88 million new cases of tuberculosis, of which 8 million will be attributable to HIV infection, will occur in the world during the decade; 30 million people are predicted to die of tuberculosis in the same period, including 2.9 million attributable to HIV infection. The number of new tuberculosis cases occurring each year is predicted to increase from 7.5 million (143 cases per 100,000) in 1990 to 8.8 million (152 per 100,000) in 1995 and 10.2 million (163 per 100,000) in the year 2000. In 1990, 2.5 million persons were estimated to have died of tuberculosis; at the same level of availability of treatment, it is predicted that 3.0 million tuberculosis deaths will occur in 1995 and 3.5 million in 2000. Demographic factors, such as population growth and changes in the age structure of populations, will account for 79.5% of the predicted increases in new cases. Age-specific incidence rates in sub-Saharan Africa are increasing due to the HIV epidemic and will account for the remaining 20.5% of the forecast increase in new cases. In WHO's South-East Asian Region and in Central and South America the age-specific incidence rates are expected to fall during 1990-2000, but at a slower rate than in previous years because of the expected increase in HIV seroprevalence.(ABSTRACT TRUNCATED AT 250 WORDS) AD - Imperial Cancer Research Fund, Radcliffe Infirmary, University of Oxford, England. AN - 8205640 AU - Dolin, P. J. AU - Raviglione, M. C. AU - Kochi, A. DP - Nlm ET - 01/01 KW - AIDS-Related Opportunistic Infections/epidemiology Adolescent Adult Age Factors Aged Child Demography Developing Countries Forecasting Humans Incidence Middle Aged Population Growth Tuberculosis/ epidemiology/mortality LA - eng N1 - Dolin, P J Raviglione, M C Kochi, A Switzerland Bulletin of the World Health Organization Bull World Health Organ. 1994;72(2):213-20. PY - 1994 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 0042-9686 (Print) 0042-9686 (Linking) SP - 213-20 ST - Global tuberculosis incidence and mortality during 1990-2000 T2 - Bull World Health Organ TI - Global tuberculosis incidence and mortality during 1990-2000 UR - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2486541/pdf/bullwho00413-0034.pdf VL - 72 ID - 2326 ER - TY - JOUR AB - The lognormal distribution typically is used to model variability in respiratory penetration values. The lognormal model is a good descriptor where the average penetration value is low, but may be a poor descriptor where the average penetration value is high because a significant fraction of penetration values could be predicted to exceed unity. In this regard, the beta distribution offers greater flexibility than the lognormal in modeling penetration values over the physically plausible interval [0,1]. The beta distribution also is shown to be mathematically convenient for describing the risk of airborne transmission of tuberculosis among a respirator-wearing population. Infection can occur following inhalation of respirable particles, termed droplet nuclei, carrying viable Mycobacterium tuberculosis bacilli. Based on the expected number of infectious doses inhaled, the Poisson probability model traditionally is used to predict an individual's risk of infection. This article synthesizes the beta distribution, as applied to average penetration values among a respirator-wearing population, and the Poisson distribution, as applied to an individual's infection risk, to describe the population risk of M. tuberculosis infection. AD - Center for Occupational and Environmental Health, School of Public Health, University of California, Berkeley 94720. AN - 8017292 AU - Nicas, M. DA - Jun DO - 10.1080/15428119491018781 [doi] DP - Nlm ET - 06/01 KW - Humans Models, Statistical Occupational Diseases/ epidemiology/ etiology Poisson Distribution Respiratory Protective Devices Risk Tuberculosis/ epidemiology/ transmission LA - eng N1 - Nicas, M United states American Industrial Hygiene Association journal Am Ind Hyg Assoc J. 1994 Jun;55(6):515-24. PY - 1994 RN - fulltext fulltext_1208 SN - 0002-8894 (Print) 0002-8894 (Linking) SP - 515-24 ST - Modeling respirator penetration values with the beta distribution: an application to occupational tuberculosis transmission T2 - Am Ind Hyg Assoc J TI - Modeling respirator penetration values with the beta distribution: an application to occupational tuberculosis transmission UR - http://www.tandfonline.com/doi/abs/10.1080/15428119491018781 VL - 55 ID - 2327 ER - TY - JOUR AB - A mathematical model is introduced to study the accelerating impact of HIV infection on the incidence rates of tuberculosis (TB) disease. A sexually active population (15-49 years) is followed cross-sectionally over a period of time. Beginning with the year in which HIV infection was probably first present in the population, the model calculates the growing yearly incidence rates of new TB disease in HIV-positive and in HIV-negative individuals. Model equations, derived by an actuarial method, are developed recursively. Input information required for the calculations includes the age distribution of the study population, pre-HIV annual TB infection rates, annual HIV infection and mortality rates, and estimates of annual TB disease breakdown rates in the absence and in the presence of HIV infection. With correct input data, the model provides a useful blueprint for health agencies in designing effective programmes for curbing the future course of these dual epidemics in the population. AD - Respiratory Division, Vancouver General Hospital, BC, Canada. AN - 8082969 AU - Schulzer, M. AU - Radhamani, M. P. AU - Grzybowski, S. AU - Mak, E. AU - Fitzgerald, J. M. DA - Apr DP - Nlm ET - 04/01 KW - AIDS-Related Opportunistic Infections/ mortality Adolescent Adult Canada/epidemiology Cross-Sectional Studies Female HIV Infections/ mortality Humans Incidence Male Middle Aged Models, Theoretical Risk Factors Survival Analysis Tuberculosis, Pulmonary/ mortality LA - eng N1 - Schulzer, M Radhamani, M P Grzybowski, S Mak, E Fitzgerald, J M Research Support, Non-U.S. Gov't England International journal of epidemiology Int J Epidemiol. 1994 Apr;23(2):400-7. PY - 1994 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 0300-5771 (Print) 0300-5771 (Linking) SP - 400-7 ST - A mathematical model for the prediction of the impact of HIV infection on tuberculosis T2 - Int J Epidemiol TI - A mathematical model for the prediction of the impact of HIV infection on tuberculosis UR - http://ije.oxfordjournals.org.ez.lshtm.ac.uk/content/23/2/400.full.pdf VL - 23 ID - 2328 ER - TY - JOUR AB - In developed countries the major tuberculosis epidemics declined long before the disease became curable in the 1940s. We present a theoretical framework for assessing the intrinsic transmission dynamics of tuberculosis. We demonstrate that it takes one to several hundred years for a tuberculosis epidemic to rise, fall and reach a stable endemic level. Our results suggest that some of the decline of tuberculosis is simply due to the natural behaviour of an epidemic. Although other factors must also have contributed to the decline, these causal factors were constrained to operate within the slow response time dictated by the intrinsic dynamics. AD - Department of Epidemiology & Biostatistics, University of California San Francisco, San Francisco General Hospital 94143-1347, USA. AN - 7585186 AU - Blower, S. M. AU - McLean, A. R. AU - Porco, T. C. AU - Small, P. M. AU - Hopewell, P. C. AU - Sanchez, M. A. AU - Moss, A. R. DA - Aug ET - 08/01 J2 - Nature medicine KW - *Disease Outbreaks Europe/epidemiology Humans *Models, Statistical Nonlinear Dynamics North America/epidemiology Sampling Studies Time Factors Tuberculosis, Pulmonary/*epidemiology/transmission LA - eng M3 - Comparative Study Research Support, U.S. Gov't, P.H.S. N1 - Blower, S M McLean, A R Porco, T C Small, P M Hopewell, P C Sanchez, M A Moss, A R 1R29DA08153/DA/NIDA NIH HHS/ AI33831/AI/NIAID NIH HHS/ K08AI01137-01/AI/NIAID NIH HHS/ Nat Med. 1995 Aug;1(8):815-21. PY - 1995 RN - fulltext fulltext_1208 SN - 1078-8956 (Print) 1078-8956 (Linking) SP - 815-21 ST - The intrinsic transmission dynamics of tuberculosis epidemics T2 - Nat Med TI - The intrinsic transmission dynamics of tuberculosis epidemics UR - http://www.ncbi.nlm.nih.gov/pubmed/7585186 VL - 1 ID - 2329 ER - TY - JOUR AB - The expected upsurge in the number of new cases of tuberculosis resulting from the HIV/AIDS epidemic prompted an examination of the feasibility of prevention strategies to limit the increase in clinical tuberculosis. A computer spreadsheet model was developed to estimate the costs and benefits that would result from isoniazid chemoprophylaxis for tuberculosis in a hypothetical cohort of 100,000 HIV-seropositive people in South Africa over a period of 8 years. At a 50% prevalence of tuberculosis infection among those at high background risk, and 5-10% among those at low risk, there would have been 34,000 cases of active tuberculosis in the cohort and their contacts if no prophylactic therapy had been used. On the other hand, a chemoprophylaxis policy would have meant only 12,200 cases of tuberculosis, if a patient compliance rate of 68.5% had been assumed. Such a policy would have prevented 21,800 cases of active tuberculosis. The estimated total discounted cost of a chemoprophylaxis programme would have been R51.3 million. In the absence of preventive therapy the discounted cost of treating patients with active tuberculosis would have been R91.9 million over the 8-year period. Therefore, if the benefits of chemoprophylaxis were defined in terms of averted health care costs, such a policy would have resulted in net savings of R40.6 million. This study did not estimate losses in production associated with tuberculosis treatment or the value of preventing tuberculosis per se, though such indirect costs would have increased the benefit of the prevention programme.(ABSTRACT TRUNCATED AT 250 WORDS) AD - Department of Community Health, University of the Witwatersrand, Johannesburg. AN - 7597538 AU - Masobe, P. AU - Lee, T. AU - Price, M. DA - Feb DP - Nlm ET - 02/01 KW - Ambulatory Care/ economics Computer Simulation Cost of Illness Costs and Cost Analysis Feasibility Studies HIV Seropositivity/ complications Hospitalization/ economics Humans Isoniazid/economics/ therapeutic use Patient Compliance South Africa Tuberculosis/economics/ prevention & control LA - eng N1 - Masobe, P Lee, T Price, M South africa South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde S Afr Med J. 1995 Feb;85(2):75-81. PY - 1995 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 0256-9574 (Print) 0256-9574 (Linking) SP - 75-81 ST - Isoniazid prophylactic therapy for tuberculosis in HIV-seropositive patients--a least-cost analysis T2 - S Afr Med J TI - Isoniazid prophylactic therapy for tuberculosis in HIV-seropositive patients--a least-cost analysis VL - 85 ID - 2330 ER - TY - JOUR AB - OBJECTIVE: To compare tuberculin screening of all kindergartners and high school entrants (screen-all strategy) vs screening limited to high-risk children (targeted screening). DESIGN: Decision, cost-effectiveness, and cost-benefit analyses. SETTING AND SUBJECTS: Students in a large urban and rural county. DEFINITIONS: High risk of tuberculosis infection was defined as birth in a county with a high prevalence of tuberculosis. Low risk was defined as birth in the United States. OUTCOME MEASURES: Tuberculosis cases prevented for 10, 000 children screened. Net costs, net cost per case prevented, benefit-cost ratio, and incremental cost-effectiveness. RESULTS: The screen-all strategy would prevent 14.9 cases per 10,000 children screened; targeted screening would prevent 84.9 cases per 10,000 children screened. The screen-all strategy is more costly than no screening; the benefit-cost ratio is 0.58. Targeted screening would result in a net savings; the benefit-cost ratio is 1.2. Screening all children is cost saving only if the reactor rate is 20% or greater. The cost per additional case prevented for screening all children compared with targeted screening (+34 666) is more than twice as high as treatment and contact tracing for a case of tuberculosis (+16 392). CONCLUSIONS: Targeted screening of schoolchildren is much less costly than mass screening and is more efficient in prevention of tuberculosis. AD - Disease Control and Prevention Division, County of Santa Clara Public Health Department, San Jose, CA, USA. AN - 7637141 AU - Mohle-Boetani, J. C. AU - Miller, B. AU - Halpern, M. AU - Trivedi, A. AU - Lessler, J. AU - Solomon, S. L. AU - Fenstersheib, M. DA - Aug 23-30 DP - Nlm ET - 08/23 J2 - JAMA : the journal of the American Medical Association KW - Adolescent California/epidemiology Child Child, Preschool Cost-Benefit Analysis/methods Decision Trees Health Care Costs/ statistics & numerical data Humans Mass Screening/ economics/standards Risk Factors School Health Services/ economics Tuberculin Test Tuberculosis/economics/epidemiology/ prevention & control LA - eng N1 - Mohle-Boetani, J C Miller, B Halpern, M Trivedi, A Lessler, J Solomon, S L Fenstersheib, M United states JAMA. 1995 Aug 23-30;274(8):613-9. PY - 1995 RN - fulltext fulltext_1208 SN - 0098-7484 (Print) 0098-7484 (Linking) SP - 613-9 ST - School-based screening for tuberculous infection. A cost-benefit analysis T2 - JAMA TI - School-based screening for tuberculous infection. A cost-benefit analysis UR - http://jama.jamanetwork.com/data/Journals/JAMA/9401/jama_274_8_037.pdf VL - 274 ID - 2331 ER - TY - JOUR AB - SETTING: National tuberculin skin test surveys. OBJECTIVES: To review the operating characteristics of the tuberculin skin test, to ascertain the validity of estimating prevalence and risk of infection from tuberculin skin test surveys under various conditions, and to review constraints in the estimation of the magnitude of the tuberculosis problem in the community from such surveys. METHODS: This report utilizes hypothetical and selected real data obtained in regional and national surveys at various points in time to exemplify methodological issues. RESULTS: Risk of infection, the essence to be abstracted from tuberculin skin test surveys, theoretically allows for a comparison of the extent of transmission of tubercle bacilli in various populations. However, the conduct of tuberculin skin test surveys and the analysis and interpretation of their results are not free from important technical problems. Accurate estimation of infection prevalence is particularly vulnerable to the great variability of the test's specificity under various circumstances. Furthermore, the annual risk of infection has averaging characteristics that preclude a rapid assessment of changes in transmission patterns. Finally, estimates of infection risk do not necessarily provide a standardized parameter to derive incidence of infectious cases, because of variations in the quality of intervention and varying risks of progression from latent infection to overt tuberculosis. CONCLUSIONS: While tuberculin skin test surveys provide the currently most widely used means of assessing tuberculosis transmission patterns over prolonged periods of time in a community, results from such surveys must be interpreted with caution when accurate estimates of the tuberculosis problem are sought. AD - Tuberculosis Section, International Union Against Tuberculosis and Lung Disease, Paris, France. AN - 7780092 AU - Rieder, H. L. DA - Apr KW - Child Child, Preschool Humans Incidence Infant Models, Statistical Predictive Value of Tests Prevalence Tanzania/epidemiology *Tuberculin Test Tuberculosis/*epidemiology/pathology LA - eng N1 - Journal Article Scotland the official journal of the International Union against Tuberculosis and Lung Disease PY - 1995 RN - fulltext fulltext_1208 SN - 0962-8479 (Print) SP - 114-121 ST - Methodological issues in the estimation of the tuberculosis problem from tuberculin surveys T2 - Tubercle and Lung Disease TI - Methodological issues in the estimation of the tuberculosis problem from tuberculin surveys UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=7780092http://ac.els-cdn.com/0962847995905529/1-s2.0-0962847995905529-main.pdf?_tid=c07e572e-6b37-11e2-a32a-00000aacb360&acdnat=1359589977_76de43cdb6962b4403e18004d77ee7f5 VL - 76 ID - 2332 ER - TY - JOUR AB - We use mathematical models to investigate the within-host dynamics of mycobacterial infections. In particular, we investigate the mechanisms by which bacteria such as Mycobacterium tuberculosis and Mycobacterium leprae persist at low densities for extended periods, and attain high densities much later. We suggest that the persistence of bacteria in face of immune pressure may result from the bacteria having a very slow growth rate, or having a dormant stage. We show that whereas these mechanisms may lead to long-term persistence, this will be obtained at relatively low densities. We then suggest that the long-term persistence of bacteria may result in the loss of immunity because of the deletion of specific T-cells arriving from the thymus, and the exhaustion of the specific T-cells as these cells reach the Hayflick limit and die. This loss of immunity will allow the bacteria to attain a high density. We propose experiments capable of testing our models and discuss the implications of the models for the treatment of infected hosts. AD - Department of Biology, Emory University, Atlanta, Georgia 30322, USA. AN - 8920248 AU - Antia, R. AU - Koella, J. C. AU - Perrot, V. DA - Mar 22 DO - 10.1098/rspb.1996.0040 [doi] DP - Nlm ET - 03/22 KW - Humans Leprosy/drug therapy/etiology/microbiology Mathematics Models, Biological Mycobacterium Infections/ etiology/microbiology Mycobacterium leprae/growth & development/immunology Mycobacterium tuberculosis/growth & development/immunology Time Factors Tuberculosis/drug therapy/etiology/microbiology LA - eng N1 - Antia, R Koella, J C Perrot, V Research Support, Non-U.S. Gov't England Proceedings. Biological sciences / The Royal Society Proc Biol Sci. 1996 Mar 22;263(1368):257-63. PY - 1996 RN - fulltext fulltext_1208 SN - 0962-8452 (Print) 0962-8452 (Linking) SP - 257-63 ST - Models of the within-host dynamics of persistent mycobacterial infections T2 - Proc Biol Sci TI - Models of the within-host dynamics of persistent mycobacterial infections UR - http://rspb.royalsocietypublishing.org/content/263/1368/257.full.pdf VL - 263 ID - 2333 ER - TY - JOUR AB - Tuberculosis, although preventable and curable, causes more adult deaths than any other infectious disease. A theoretical framework for designing effective control strategies is developed and used to determine treatment levels for eradication, to assess the effects of noneradicating control, and to examine the global goals of the World Health Organization. The theory is extended to assess how suboptimal control programs contribute to the evolution of drug resistance. A new evaluation criterion is defined and used to suggest how control strategies can be improved. In order to control tuberculosis, treatment failure rates must be lower in developing countries than in developed countries. AD - Department of Epidemiology and Biostatistics, University of California San Francisco, CA 94143-1347, USA. AN - 8662538 AU - Blower, S. M. AU - Small, P. M. AU - Hopewell, P. C. DA - Jul 26 ET - 07/26 J2 - Science KW - Adult Antitubercular Agents/*therapeutic use Developed Countries Developing Countries Disease Outbreaks/*prevention & control Drug Resistance, Microbial Humans *Models, Biological Models, Statistical Mycobacterium tuberculosis/drug effects Treatment Failure Tuberculosis, Multidrug-Resistant/drug therapy/*epidemiology/transmission Tuberculosis, Pulmonary/microbiology/*prevention & control/transmission World Health Organization L1 - internal-pdf://0696966960/Blower-1996-Control strategies for tuberculosi.pdf LA - eng M3 - Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. N1 - Blower, S M Small, P M Hopewell, P C 1R29DA08153/DA/NIDA NIH HHS/ AI33831/AI/NIAID NIH HHS/ AI35969/AI/NIAID NIH HHS/ New York, N.Y. Science. 1996 Jul 26;273(5274):497-500. PY - 1996 RN - fulltext fulltext_1208 SN - 0036-8075 (Print) 0036-8075 (Linking) SP - 497-500 ST - Control strategies for tuberculosis epidemics: new models for old problems T2 - Science TI - Control strategies for tuberculosis epidemics: new models for old problems UR - http://www.ncbi.nlm.nih.gov/pubmed/8662538 http://science.sciencemag.org/content/sci/273/5274/497.full.pdf VL - 273 ID - 2334 ER - TY - JOUR AB - OBJECTIVE: To develop more effective methods to assess tuberculosis (TB) control strategies so we can meet national goals for the elimination of TB in the United States. DESIGN: Using a semi-Markov model that divided the US population into 3 age groups and 18 clinical states based on disease status and risk for TB and human immunodeficiency virus (HIV) infection, we measured the effects of 5 changes in TB policy, introduced singly and in combination: (1) increased coverage and (2) improved efficacy of preventive therapy, (3) increased coverage and (4) improved efficacy of treatment, and (5) introduction of BCG vaccination. RESULTS: A BCG vaccination program that reached 10% of eligible children and 1% of eligible adults each year would produce a 17% reduction in cases and an 11% decline in deaths over 10 years. Preventive therapy programs among the general population would have little effect on the number of TB cases, but a program targeting HIV-infected patients would reduce HIV-associated TB cases and deaths 14% to 20%. A 10% improvement in the coverage and efficacy of both preventive therapy and treatment, coupled with the BCG vaccination program, would lead to a 47% decline in TB cases and a 50% decline in TB deaths relative to baseline over 10 years. CONCLUSIONS: Improvements in treatment coverage or effectiveness alone are unlikely to reach established national goals for the elimination of TB. These goals can be achieved through a combination of improvements in current programs with targeted preventive therapy and BCG vaccination programs. AD - Channing Laboratory, Brigham and Women's Hospital, Boston, Mass 02115, USA. AN - 8968016 AU - Brewer, T. F. AU - Heymann, S. J. AU - Colditz, G. A. AU - Wilson, M. E. AU - Auerbach, K. AU - Kane, D. AU - Fineberg, H. V. DA - Dec 18 DP - Nlm ET - 12/18 KW - Adolescent Adult Age Distribution Antitubercular Agents/therapeutic use BCG Vaccine Child Communicable Disease Control HIV Infections Humans Middle Aged Models, Theoretical Policy Making Probability Tuberculosis/epidemiology/ prevention & control Tuberculosis, Multidrug-Resistant United States/epidemiology L1 - internal-pdf://0346664946/Brewer-1996-Evaluation of tuberculosis control.pdf LA - eng N1 - Brewer, T F Heymann, S J Colditz, G A Wilson, M E Auerbach, K Kane, D Fineberg, H V 1 F32 HS00079/HS/AHRQ HHS/United States Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. United states JAMA : the journal of the American Medical Association JAMA. 1996 Dec 18;276(23):1898-903. PY - 1996 RN - fulltext fulltext_1208 SN - 0098-7484 (Print) 0098-7484 (Linking) SP - 1898-903 ST - Evaluation of tuberculosis control policies using computer simulation T2 - JAMA TI - Evaluation of tuberculosis control policies using computer simulation UR - http://jama.jamanetwork.com/article.aspx?articleid=411957 https://jamanetwork.com/journals/jama/articlepdf/411957/jama_276_23_034.pdf VL - 276 ID - 2335 ER - TY - JOUR AU - Moore, R. D. AU - Chaulk, C. P. AU - Griffiths, R. AU - Cavalcante, S. AU - Chaisson, R. E. DA - 1996 J2 - Am.J.Respir.Crit.Care Med. KW - control cost effectiveness DOT interventions tuberculosis LB - 4779 N1 - TY - JOUR TB Tuberculosis control Treatment No sub-heading Directly observed therapy PY - 1996 RN - fulltext fulltext_1208 SP - 1013-1019 ST - Cost-effectiveness of directly observed versus self-administered therapy for tuberculosis T2 - Am.J.Respir.Crit.Care Med. TI - Cost-effectiveness of directly observed versus self-administered therapy for tuberculosis VL - 154 ID - 2336 ER - TY - JOUR AB - An adverse health impact is often treated as a binary variable (response vs. no response), in which case the risk of response is defined as a monotonically increasing function R of the dose received D. For a population of size N, specifying the forms of R(D) and of the probability density function (pdf) for D allows determination of the pdf for risk, and computation of the mean and variance of the distribution of incidence, where the latter parameters are denoted E[SN] and Var[SN], respectively. The distribution of SN describes uncertainty in the future incidence value. Given variability in dose (and risk) among population members, the distribution of incidence is Poisson-binomial. However, depending on the value of E[SN], the distribution of incidence is adequately approximated by a Poisson distribution with parameter mu = E[SN], or by a normal distribution with mean and variance equal to E[SN] and Var[SN]. The general analytical framework is applied to occupational infection by Mycobacterium tuberculosis (M. tb). Tuberculosis is transmitted by inhalation of 1-5 microns particles carrying viable M. tb bacilli. Infection risk has traditionally been modeled by the expression: R(D) = 1 - exp(-D), where D is the expected number of bacilli that deposit in the pulmonary region. This model assumes that the infectious dose is one bacillus. The beta pdf and the gamma pdf are shown to be reasonable and especially convenient forms for modeling the distribution of the expected cumulative dose across a large healthcare worker cohort. Use of the the analytical framework is illustrated by estimating the efficacy of different respiratory protective devices in reducing healthcare worker infection risk. AD - Center for Occupational and Environmental Health, School of Public Health, University of California, Berkeley 94720, USA. AN - 8819343 AU - Nicas, M. DA - Aug DP - Nlm ET - 08/01 KW - Cohort Studies Health Personnel Humans Models, Biological Occupational Diseases/epidemiology/ etiology/prevention & control Poisson Distribution Respiratory Protective Devices Risk Assessment Risk Factors Tuberculosis, Pulmonary/epidemiology/ etiology/prevention & control LA - eng N1 - Nicas, M United states Risk analysis : an official publication of the Society for Risk Analysis Risk Anal. 1996 Aug;16(4):527-38. PY - 1996 RN - fulltext fulltext_1208 SN - 0272-4332 (Print) 0272-4332 (Linking) SP - 527-38 ST - An analytical framework for relating dose, risk, and incidence: an application to occupational tuberculosis infection T2 - Risk Anal TI - An analytical framework for relating dose, risk, and incidence: an application to occupational tuberculosis infection VL - 16 ID - 2337 ER - TY - JOUR AB - STUDY OBJECTIVES: To compare the costs and effectiveness of directly observed therapy (DOT) vs self-administered therapy (SAT) for the treatment of active tuberculosis. DESIGN: Decision analysis. SETTING: We used published rates for failure of therapy, relapse, and acquired multidrug resistance during the initial treatment of drug-susceptible tuberculosis cases using DOT or SAT. We estimated costs of tuberculosis treatment at an urban tuberculosis control program, a municipal hospital, and a hospital specializing in treating drug-resistant tuberculosis. OUTCOME MEASURES: The average cost per patient to cure drug-susceptible tuberculosis, including the cost of treating failures of initial treatment. RESULTS: The direct costs of initial therapy with DOT and SAT were similar ($1,206 vs $1,221 per patient, respectively), although DOT was more expensive when patient time costs were included. When the costs of relapse and failure were included in the model, DOT was less expensive than SAT, whether considering outpatient costs only ($1,405 vs $2,314 per patient treated), outpatient plus inpatient costs ($2,785 vs $10,529 per patient treated), or outpatient, inpatient, and patients' time costs ($3,999 vs $12,167 per patient treated). Threshold analysis demonstrated that DOT was less expensive than SAT through a wide range of cost estimates and clinical event rates. CONCLUSION: Despite its greater initial cost, DOT is a more cost-effective strategy than SAT because it achieves a higher cure rate after initial therapy, and thereby decreases treatment costs associated with failure of therapy and acquired drug resistance. This cost-effectiveness analysis supports the widespread implementation of DOT. AD - Denver Disease Control Service, Denver Health and Hospitals, and the Department of Medicine, University of Colorado Health Sciences Center, 80204, USA. AN - 9228359 AU - Burman, W. J. AU - Dalton, C. B. AU - Cohn, D. L. AU - Butler, J. R. AU - Reves, R. R. DA - Jul ET - 07/01 KW - Antitubercular Agents/*administration & dosage/economics/therapeutic use Communicable Disease Control/economics Cost-Benefit Analysis Costs and Cost Analysis *Decision Support Techniques Drug Therapy, Combination Hospital Costs Humans Patient Compliance Self Administration Treatment Failure Tuberculosis/*drug therapy/*economics/epidemiology Tuberculosis, Multidrug-Resistant/*drug therapy/*economics/epidemiology United States/epidemiology LA - eng N1 - Burman, W J Dalton, C B Cohn, D L Butler, J R Reves, R R Comparative Study United states Chest Chest. 1997 Jul;112(1):63-70. PY - 1997 RN - fulltext fulltext_1208 SN - 0012-3692 (Print) 0012-3692 (Linking) SP - 63-70 ST - A cost-effectiveness analysis of directly observed therapy vs self-administered therapy for treatment of tuberculosis T2 - Chest TI - A cost-effectiveness analysis of directly observed therapy vs self-administered therapy for treatment of tuberculosis UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=9228359 VL - 112 ID - 2338 ER - TY - JOUR AB - Incomplete treatment of patients with infectious tuberculosis (TB) may not only lead to relapse but also to the development of antibiotic resistant TB-one of the most serious health problems facing society today. In this article, we formulate one-strain and two-strain TB models to determine possible mechanisms that may allow for the survival and spread of naturally resistant strains of TB as well as antibiotic-generated resistant strains of TB. Analysis of our models shows that non-antibiotic co-existence is possible but rare for naturally resistant strains while co-existence is almost the rule for strains that result from the lack of compliance with antibiotic treatment by TB infected individuals. AD - Biometrics Unit, Cornell University, Ithaca, NY 14853, USA. AN - 9225454 AU - Castillo-Chavez, C. AU - Feng, Z. DA - Jun ET - 06/01 KW - Antitubercular Agents/*pharmacology *Drug Resistance, Microbial Humans *Models, Theoretical Tuberculosis/*drug therapy/epidemiology L1 - internal-pdf://1263453073/10.1.1.1015.3529.pdf LA - eng N1 - Castillo-Chavez, C Feng, Z Research Support, U.S. Gov't, Non-P.H.S. Germany Journal of mathematical biology J Math Biol. 1997 Jun;35(6):629-56. PY - 1997 RN - fulltext fulltext_1208 SN - 0303-6812 (Print) 0303-6812 (Linking) SP - 629-656 ST - To treat or not to treat: the case of tuberculosis T2 - Journal of Mathematical Biology TI - To treat or not to treat: the case of tuberculosis UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=9225454 VL - 35 ID - 2339 ER - TY - JOUR AB - OBJECTIVE: To assess the economic benefits and costs of providing isoniazid preventive therapy for tuberculosis (TB) in HIV-infected persons in Zambia. DESIGN: A spreadsheet model incorporating variables drawn from published studies and unpublished data. SUBJECTS: Data drawn from a number of different studies and published literature involving a range of subjects. SETTING: Zambia. RESULTS: Using data primarily from Zambia we have modelled the costs and benefits of a TB preventive therapy programme using daily isoniazid for 6 months. The basecase scenario assumes recruitment at a voluntary testing and counselling site where HIV seroprevalence is 30%; persons with HIV have a 25% probability of developing active TB during their lifetime; two additional cases of TB would be prevented per person completing a course of preventive therapy; compliance would be 63%, and the efficacy of the isoniazid in preventing active TB of 60%. The costs under this scenario would exceed the benefits by a factor of 1.16 [benefit: cost ratio (BCR) of 0.86]. However, if preventing one case of TB prevented an additional five cases, the benefits would exceed the costs by a significant margin (BCR of 1.71). Other scenarios indicate that the targeted preventive therapy of persons with HIV whose occupation or living situation places them in contact with a large number of others (teachers and students, health personnel, military and police, miners, prisoners, etc.) would yield significant net benefit. The operational challenge for TB preventive therapy is thus to identify and target large numbers of such persons. AD - Department of Public Health and Policy, London School of Hygiene and Tropical Medicine, UK. AN - 9189218 AU - Foster, S. AU - Godfrey-Faussett, P. AU - Porter, J. DA - Jun DP - Nlm ET - 06/01 KW - AIDS-Related Opportunistic Infections/economics/ prevention & control Antitubercular Agents/economics/ therapeutic use Cost-Benefit Analysis Humans Isoniazid/economics/ therapeutic use Models, Economic Tuberculosis/economics/ prevention & control Zambia the economic costs and benefits of providing daily isoniazid preventive therapy for tuberculosis (TB) for 6 months in HIV-infected persons in Zambia. The base case scenario assumes recruitment at a voluntary testing and counseling site where HIV seroprevalence is 30%, HIV-infected individuals have a 25% probability of developing active TB during their lifetime, two additional cases of TB would be prevented per person completing a course of preventive therapy, compliance would be 63%, and an efficacy of isoniazid in preventing active TB of 60%. The costs under that scenario would exceed benefits by a factor of 1.16, or a benefit/cost ratio (BCR) of 0.86. However, if preventing one case of TB prevented an additional five cases, the benefits would exceed the costs by a BCR of 1.71. Other scenarios indicate likely significant net benefits from the targeted preventive therapy of HIV-infected persons whose occupation or living situation brings them into contact with a large number of other people. LA - eng N1 - Foster, S Godfrey-Faussett, P Porter, J Research Support, Non-U.S. Gov't United states AIDS (London, England) AIDS. 1997 Jun;11(7):919-25. PY - 1997 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 0269-9370 (Print) 0269-9370 (Linking) SP - 919-25 ST - Modelling the economic benefits of tuberculosis preventive therapy for people with HIV: the example of Zambia T2 - AIDS TI - Modelling the economic benefits of tuberculosis preventive therapy for people with HIV: the example of Zambia UR - http://graphics.tx.ovid.com/ovftpdfs/FPDDNCDCLFEDDD00/fs047/ovft/live/gv031/00002030/00002030-199707000-00012.pdf VL - 11 ID - 2340 ER - TY - JOUR AB - We evaluated the efficacy of recommended tuberculosis (TB) infection control measures by using a deterministic mathematical model for airborne contagion. We examined the percentage of purified protein derivative conversions under various exposure conditions, environmental controlstrategies, and respiratory protective devices. We conclude that environmental control cannot eliminate the risk for TB transmission during high-risk procedures; respiratory protective devices, and particularly high-efficiency particulate air masks, may provide nearly complete protection if used with air filtration or ultraviolet irradiation. Nevertheless, the efficiency of these control measures decreases as the infectivity of the source case increases. Therefore, administrative control measures (e.g., indentifying and isolating patients with infectious TB) are the most effective because they substantially reduce the rate of infection. AD - Dipartimento di Matematica, Universita di Perugia, Perugia, Italy. AN - 9284378 AU - Gammaitoni, L. AU - Nucci, M. C. DA - Jul-Sep DP - Nlm ET - 07/01 KW - Cross Infection/prevention & control/transmission Disease Outbreaks Europe/epidemiology Health Personnel Humans Mathematics Models, Biological Occupational Diseases/prevention & control Respiratory Protective Devices Risk Factors Tuberculosis, Pulmonary/epidemiology/ prevention & control/transmission United States/epidemiology LA - eng N1 - Gammaitoni, L Nucci, M C Research Support, Non-U.S. Gov't Review United states Emerging infectious diseases Emerg Infect Dis. 1997 Jul-Sep;3(3):335-42. PY - 1997 RN - fulltext fulltext_1208 SN - 1080-6040 (Print) 1080-6040 (Linking) SP - 335-42 ST - Using a mathematical model to evaluate the efficacy of TB control measures T2 - Emerg Infect Dis TI - Using a mathematical model to evaluate the efficacy of TB control measures VL - 3 ID - 2341 ER - TY - JOUR AB - BACKGROUND: Tuberculosis has been declining in developed countries for a long time, as a result of the intrinsic epidemiological characteristics of this disease, combined with improvement in the standard of living and more recently the use of antibiotics. In these low prevalence countries, decisions concerning the objectives of tuberculosis programmes have to be taken and the consequences of short term changes in the sanitary situation have to be assessed. METHODS: A deterministic model, without age structure, of the dynamics of pulmonary tuberculosis is proposed. The model extends that of Waaler and is intended to be more suitable for application to developed countries. The flows between seven subgroups of population, based on the natural history of the disease, are modelled and vaccination is taken into account. Values of model parameters and initial prevalences were deduced from published data. RESULTS: As a first step, qualitative comparisons are performed between the model-predicted decline in the annual risk of infection (ARI) and data from the Netherlands tuberculosis survey. Using parameter values suited to France, our model shows that the predicted decline is slower in France than in the Netherlands; a result which tallies with epidemiological observations. Uses of the model as a decision tool are illustrated in two cases, that of ending systematic BCG vaccination and that of a sudden increase in the number of infectious cases. AD - Institut Francais de Recherche Scientifique, Developpement en Cooperation, (ORSTOM), Paris, France. AN - 9126520 AU - Garcia, A. AU - Maccario, J. AU - Richardson, S. DA - Feb DP - Nlm ET - 02/01 KW - Epidemiologic Methods France/epidemiology Humans Incidence Models, Theoretical Netherlands/epidemiology Risk Assessment Time Factors Tuberculosis/ epidemiology LA - eng N1 - Garcia, A Maccario, J Richardson, S Comparative Study Research Support, Non-U.S. Gov't England International journal of epidemiology Int J Epidemiol. 1997 Feb;26(1):190-203. PY - 1997 RN - fulltext fulltext_1208 SN - 0300-5771 (Print) 0300-5771 (Linking) SP - 190-203 ST - Modelling the annual risk of tuberculosis infection T2 - Int J Epidemiol TI - Modelling the annual risk of tuberculosis infection UR - http://ije.oxfordjournals.org/content/26/1/190.full.pdf VL - 26 ID - 2342 ER - TY - JOUR AB - For tuberculosis and number of other bacterial infections, treatment with a single antimicrobial drug frequently fails due to the ascent of mutants resistant to that drug. To minimize the likelihood of this occurrence, multiple drugs with independent resistance mechanisms are used simultaneously. None the less, multiply resistant bacteria sometimes emerge even when patients are simultaneously treated with two or more drugs, and the ascent of these multiply-resistant mutants may result in treatment failure in the patient and spread of these resistant bacteria to other hosts. We consider two mathematical models of antibacterial chemotherapy which can account for the ascent of multiple antibiotic resistance within hosts treated with multiple antibiotics. In both, multiple resistance evolves because of selection favouring mutants resistant to fewer than all of the chemotherapeutic agents employed, intermediates. In one model, this occurs because of temporal fluctuations in the concentrations of the antibiotics in the course of normal treatment and/or because of non-adherence to the treatment regime. In the other, intermediates are favoured and multiple resistance evolves because of tissue and somatic cell heterogeneity. In the effective concentrations of the antibiotics and physiological variation in the sensitivity of subpopulations of bacteria to different antibiotics. We discuss the limitations (and assets) of this model and approach and the implications for the design of antibiotic treatment regimes. Finally, we consider how the assumptions behind this model and the predictions made from its analysis could be tested experimentally. AD - Department of Biology, Emory University, Atlanta, GA 30322, USA. AN - 9189638 AU - Lipsitch, M. AU - Levin, B. R. DP - NLM ET - 1997/01/01 J2 - Ciba Foundation symposium KW - Animals Anti-Bacterial Agents/*therapeutic use Bacteria/*drug effects Bacterial Infections/*drug therapy Biological Evolution *Drug Resistance, Multiple/genetics Humans *Models, Biological *Models, Theoretical LA - eng N1 - Lipsitch, M Levin, B R GM33782/GM/NIGMS NIH HHS/United States Journal Article Research Support, U.S. Gov't, P.H.S. Review Netherlands Ciba Found Symp. 1997;207:112-27; discussion 127-30. PY - 1997 SN - 0300-5208 (Print) 0300-5208 SP - 112-27; discussion 127-30 ST - The within-host population dynamics of antibacterial chemotherapy: conditions for the evolution of resistance T2 - Ciba Found Symp TI - The within-host population dynamics of antibacterial chemotherapy: conditions for the evolution of resistance VL - 207 ID - 3175 ER - TY - JOUR AU - Marcus, Alexander M. AU - Rose, David N. AU - Sacks, Henry S. AU - Schechter, Clyde B. DO - 10.1006/pmed.1996.0123 KW - Bacille Calmette-Guérin BCG health care worker isoniazid occupational health prevention tuberculin tuberculosis vaccination PY - 1997 RN - fulltext fulltext_1208 SN - 0091-7435 SP - 201-207 ST - BCG Vaccination to Prevent Tuberculosis in Health Care Workers: A Decision Analysis T2 - Preventive Medicine TI - BCG Vaccination to Prevent Tuberculosis in Health Care Workers: A Decision Analysis UR - http://www.sciencedirect.com/science/article/pii/S0091743596901231 VL - 26 ID - 2345 ER - TY - JOUR AB - BACKGROUND: Tuberculin skin testing using the purified protein derivative is recommended as part of a tuberculosis control program for health care workers. However, compliance with skin testing programs has been poor and their cost-effectiveness is unknown. METHODS: A Markov-based decision analysis was performed to determine the cost-effectiveness of tuberculin skin testing over the entire lifetimes of physicians who are now in medical school. Assumptions were deliberately chosen to present a conservative estimate of cost-effectiveness. Indirect costs were not included. RESULTS: Annual testing cost $29,000 per life-year saved and $39,000 per case of pulmonary tuberculosis prevented. In contrast, particulate respirators have been shown to cost millions of dollars per case prevented. Skin testing every 6 months was cost-effective in a subpopulation at high risk of infection (> or = 1.8-fold). During their entire lifetimes, physicians now in medical school can expect to avert 137 cases of pulmonary tuberculosis, prevent 7 tuberculosis deaths, and save 182 life-years because of skin testing programs. Improved compliance with annual skin testing and prophylactic isoniazid could more than triple this benefit. If available, a moderately effective vaccine would be even more cost-effective than tuberculin skin testing programs. CONCLUSIONS: Tuberculin skin testing is cost-effective and should be an integral part of any tuberculosis control program. Vaccination may one day be a feasible and cost-effective alternative to skin testing programs. AD - Department of Internal Medicine, Virginia Commonwealth University, Richmond, USA. AN - 9164378 AU - Nettleman, M. D. AU - Geerdes, H. AU - Roy, M. C. DA - May 26 DP - Nlm ET - 05/26 J2 - Archives of internal medicine KW - Adult Aged Antitubercular Agents/therapeutic use BCG Vaccine/ economics Cause of Death Chemoprevention Cooperative Behavior Cost-Benefit Analysis Decision Support Techniques Feasibility Studies Humans Isoniazid/therapeutic use Markov Chains Middle Aged Occupational Diseases/ prevention & control Physicians Respiratory Protective Devices/economics Risk Factors Sensitivity and Specificity Time Factors Tuberculin Test/ economics Tuberculosis, Pulmonary/ prevention & control Value of Life LA - eng N1 - Nettleman, M D Geerdes, H Roy, M C United states Arch Intern Med. 1997 May 26;157(10):1121-7. PY - 1997 RN - fulltext fulltext_1208 SN - 0003-9926 (Print) 0003-9926 (Linking) SP - 1121-7 ST - The cost-effectiveness of preventing tuberculosis in physicians using tuberculin skin testing or a hypothetical vaccine T2 - Arch Intern Med TI - The cost-effectiveness of preventing tuberculosis in physicians using tuberculin skin testing or a hypothetical vaccine UR - http://archinte.jamanetwork.com/data/Journals/INTEMED/17545/archinte_157_10_009.pdf VL - 157 ID - 2346 ER - TY - JOUR AB - A simulation model of tuberculosis (TB) transmission among hospital employees is described. A hypothetical cohort of 1000 workers was divided into low-, medium-, and high-risk groups. The number of TB patients admitted daily was treated as a Poisson random variable. A patient imparted a daily infection risk that was identical for all workers within a risk group but that varied between risk groups. In some scenarios, infected employees were assigned a daily risk of developing TB disease. If disease developed, the individual remained on the job for 3 calendar weeks and imparted a substantial infection risk to 25 close contacts. Simulations were run over 5-year intervals. Cumulative infection incidence increased over time and with more TB patients admitted. Given a scenario in which there were 600, 300, and 100 susceptibles in the low-, medium-, and high risk groups, respectively, 50 TB patients admitted annually and accounting for disease among infected employees, at 5 years there were approximately 100 primary infections (due to infection by patients), 40 secondary infections (due to infection by diseased coworkers), five primary disease cases, and two secondary disease cases. The input parameter values and simulation outcomes were reasonably consistent with the sparse information reported in the literature. AD - Nicas, M (reprint author), UNIV CALIF BERKELEY,SCH PUBL HLTH,CTR ENVIRONM & OCCUPAT HLTH,BERKELEY,CA 94720, USA. AN - WOS:A1997YK07100009 AU - Nicas, M. AU - Seto, E. DA - Oct DO - 10.1111/j.1539-6924.1997.tb00901.x IS - 5 J2 - Risk Anal. KW - tuberculosis risk modeling occupational tuberculosis infection-control programs cdc tb survey member hospitals risk Public, Environmental & Occupational Health Mathematics Mathematical Methods In Social Sciences LA - English M3 - Article N1 - ISI Document Delivery No.: YK071 Times Cited: 2 Cited Reference Count: 16 Nicas, M Seto, E Niosh cdc hhs [k01-oh00155-01] 3 0 Plenum publ corp New york PY - 1997 SN - 0272-4332 SP - 609-616 ST - A simulation model for occupational tuberculosis transmission T2 - Risk Analysis TI - A simulation model for occupational tuberculosis transmission UR - ://WOS:A1997YK07100009 VL - 17 ID - 6347 ER - TY - JOUR AB - BACKGROUND: Isoniazid chemoprophylaxis effectively prevents the development of active infectious tuberculosis. Current guidelines recommend withholding this prophylaxis for low-risk tuberculin reactors older than 35 years of age because of the risk for fatal isoniazid-induced hepatitis. However, recent studies have shown that monitoring for hepatotoxicity can significantly reduce the risk for isoniazid-related death. OBJECTIVE: To evaluate the effectiveness and cost-effectiveness of monitored isoniazid prophylaxis for low-risk tuberculin reactors older than 35 years of age. DESIGN: A Markov model was used to compare the health and economic outcomes of prescribing or withholding a course of prophylaxis for low-risk reactors 35, 50, or 70 years of age. Subsequent analyses evaluated costs and benefits when the effect of transmission of Mycobacterium tuberculosis to contacts was included. MEASUREMENTS: Probability of survival at 1 year, number needed to treat, life expectancy, and cost per year of life gained for individual persons and total population. RESULTS: Isoniazid prophylaxis increased the probability of survival at 1 year and for all subsequent years. For 35-year old, 50-year-old, and 70-year-old tuberculin reactors, life expectancy increased by 4.9 days, 4.7 days, and 3.1 days, respectively, and costs per person decreased by $101, $69, and $11, respectively. When the effect of secondary transmission to contacts was included, the gains in life expectancy per person receiving prophylaxis were 10.0 days for 35-year-old reactors, 9.0 days for 50-year-old reactors, and 6.0 days for 70-year-old reactors. Costs per person for these cohorts decreased by $259, $203, and $100, respectively. The magnitude of the benefit of isoniazid prophylaxis is moderately sensitive to the effect of isoniazid on quality of life. The hypothetical provision of isoniazid prophylaxis for all low-risk reactors older than 35 years of age in the U.S. population could prevent 35,176 deaths and save $2.11 billion. CONCLUSIONS: Monitored isoniazid prophylaxis reduces mortality rates and health care costs for low-risk tuberculin reactors older than 35 years of age, although reductions for individual patients are small. For the U.S. population, however, the potential health benefits and economic savings resulting from wider use of monitored isoniazid prophylaxis are substantial. We should consider expanding current recommendations to include prophylaxis for tuberculin reactors of all ages with no contraindications. AD - Santa Clara Valley Medical Center, San Jose, California USA. AN - 9412307 AU - Salpeter, S. R. AU - Sanders, G. D. AU - Salpeter, E. E. AU - Owens, D. K. DA - Dec 15 DP - Nlm ET - 12/31 J2 - Annals of internal medicine KW - Adult Aged Antitubercular Agents/adverse effects/economics/ therapeutic use Cost-Benefit Analysis Decision Trees Drug-Induced Liver Injury/etiology/mortality Health Care Costs Humans Isoniazid/adverse effects/economics/ therapeutic use Life Expectancy Markov Chains Middle Aged Quality of Life Sensitivity and Specificity Tuberculin Test Tuberculosis/ prevention & control/transmission LA - eng N1 - Salpeter, S R Sanders, G D Salpeter, E E Owens, D K Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. United states Ann Intern Med. 1997 Dec 15;127(12):1051-61. PY - 1997 RN - fulltext fulltext_1208 SN - 0003-4819 (Print) 0003-4819 (Linking) SP - 1051-61 ST - Monitored isoniazid prophylaxis for low-risk tuberculin reactors older than 35 years of age: a risk-benefit and cost-effectiveness analysis T2 - Ann Intern Med TI - Monitored isoniazid prophylaxis for low-risk tuberculin reactors older than 35 years of age: a risk-benefit and cost-effectiveness analysis UR - http://annals.org/data/Journals/AIM/19897/0000605-199712150-00001.pdf VL - 127 ID - 2347 ER - TY - JOUR AB - The basic reproductive rate (R0) is a measure of the severity of an epidemic. On the basis of replicated Latin hypercube sampling, the authors performed an uncertainty and sensitivity analysis of the basic reproductive rate of tuberculosis (TB). The uncertainty analysis allowed for the derivation of a frequency distribution for R0 and the assessment of the relative contribution each of the three components of R0 made when TB epidemics first arose centuries ago. (The three components of R0 are associated with fast, slow, and relapse TB.) R0 estimates indicated the existence of fairly severe epidemics when TB epidemics first arose. The R0 for the susceptible persons who developed TB slowly (R0(slow)) contributed the most to the R0 estimates; however, the relative R0(slow) contribution decreased as the severity of TB epidemics increased. The sensitivity of the magnitude of R0 to the uncertainty in estimating values of each of the input parameters was assessed. These results indicated that five of the nine input parameters, because of their estimation uncertainty, were influential in determining the magnitude of R0. This uncertainty and sensitivity methodology provides results that can aid investigators in understanding the historical epidemiology of TB by quantifying the effect of the transmission processes involved. Additionally, this method can be applied to the R0 of any other infectious disease to estimate the probability of an epidemic outbreak. AD - Epidemiology Program School of Public Health, University of California, Berkeley, USA. AN - 9199543 AU - Sanchez, M. A. AU - Blower, S. M. DA - Jun 15 DP - Nlm ET - 06/15 KW - Adult Aged Disease Outbreaks/ statistics & numerical data Disease Transmission, Infectious Humans Incidence Life Expectancy Middle Aged Models, Statistical Population Dynamics Reproduction Sample Size Survival Rate Tuberculosis/ epidemiology/transmission LA - eng N1 - Sanchez, M A Blower, S M 1R29DA08153/DA/NIDA NIH HHS/United States AI33831/AI/NIAID NIH HHS/United States D43-TW00003/TW/FIC NIH HHS/United States Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. United states American journal of epidemiology Am J Epidemiol. 1997 Jun 15;145(12):1127-37. PY - 1997 RN - fulltext fulltext_1208 SN - 0002-9262 (Print) 0002-9262 (Linking) SP - 1127-37 ST - Uncertainty and sensitivity analysis of the basic reproductive rate. Tuberculosis as an example T2 - Am J Epidemiol TI - Uncertainty and sensitivity analysis of the basic reproductive rate. Tuberculosis as an example UR - http://aje.oxfordjournals.org/content/145/12/1127.full.pdf VL - 145 ID - 2348 ER - TY - JOUR AB - The study evaluates the economic costs and benefits of improving tuberculosis control interventions in Thailand. Provider costs are determined on the basis of marginal treatment costs for varying case numbers and estimates of the cost of required infrastructure changes. Indirect costs are calculated as income lost due to morbidity and premature mortality. An epidemiological model is used to calculate case numbers and mortality under current control conditions and a scenario of improved control. An improved control strategy initially leads to a higher number of detected cases. For longer projection periods, the epidemiological impact of curing a higher proportion of infectious sources results in lower case numbers than those expected without programme improvement. Model simulations show a reduction of total annual case numbers through improved control measures by an average 45% after a simulation period of 20 years. The corresponding societal savings in form of reduced indirect costs from the disease are U.S.$2.4 billion. Reductions in direct provider costs can be expected as a result of decreased numbers of detected cases for longer evaluation periods, as well as a lower proportion of multi-drug-resistant cases. The mean value of predicted savings is U.S.$8.3 million. Since this value is likely to be higher than the required investment in improved infrastructure, net savings can be expected. The result of an uncertainty analysis shows a wide range of potential additional costs or net savings with respect to direct provider costs. Indirect cost calculations show net savings for all parameter values. AD - Global Tuberculosis Programme, World Health Organization, Geneva, Switzerland. AN - 9194242 AU - Sawert, H. AU - Kongsin, S. AU - Payanandana, V. AU - Akarasewi, P. AU - Nunn, P. P. AU - Raviglione, M. C. DA - Jun IS - 12 KW - Communicable Disease Control/*economics Cost Savings *Cost of Illness Cost-Benefit Analysis Forecasting *Health Care Costs Humans Models, Statistical Morbidity Risk Factors Thailand/epidemiology Tuberculosis/*economics/epidemiology/*prevention & control Value of Life L1 - internal-pdf://3098386177/1-s2.0-S0277953696002894-main.pdf N1 - Sawert, H Kongsin, S Payanandana, V Akarasewi, P Nunn, P P Raviglione, M C eng England 1997/06/01 Soc Sci Med. 1997 Jun;44(12):1805-16. PY - 1997 SN - 0277-9536 (Print) 0277-9536 (Linking) SP - 1805-16 ST - Costs and benefits of improving tuberculosis control: the case of Thailand T2 - Soc Sci Med TI - Costs and benefits of improving tuberculosis control: the case of Thailand UR - https://www.ncbi.nlm.nih.gov/pubmed/9194242 VL - 44 ID - 2702 ER - TY - JOUR AU - Smith, P. J. AU - Thompson, T. J. AU - Jereb, J. A. DA - 1997 KW - epidemiology models morbidity outbreaks tuberculosis LB - 5102 N1 - TY - JOUR TB Transmission, pathogenesis, and epidemiology Tuberculosis Predict epi: prospects for the epidemic PY - 1997 RN - fulltext fulltext_1208 SP - 485-496 ST - A model for interval-censored tuberculosis outbreak data T2 - Stat.Med. TI - A model for interval-censored tuberculosis outbreak data VL - 16 ID - 2349 ER - TY - JOUR AB - Many aspects of the natural history of tuberculosis are poorly understood. Though it is recognized that clinical tuberculosis may follow shortly after initial infection ('primary' disease), or many years thereafter through either endogenous reactivation or after reinfection, the relative importance of these mechanisms is often disputed. The issue is complicated by the fact that the risks of developing disease are age-dependent, and reflect infection risks which may change over time. This paper estimates the age-dependent risks of developing tuberculosis using an age-structured deterministic model of the dynamics of tuberculous infection and disease in England and Wales since 1900. The work extends the classical studies of Sutherland and colleagues. The best estimates of the risks of developing 'primary' disease (within 5 years of initial infection) were approximately 4%, 9% and 14% for individuals infected at ages 0-10, 15 years and over 20 years respectively, and a previous infection appeared to impart little protection against (further) reinfection, but 16-41% protection against disease subsequent to reinfection for adolescents and adults. We also provide evidence that reinfection made an important contribution to tuberculous morbidity in the past, as (i) exclusion of exogenous disease from the model considerably worsened the fit to observed notification rates, and (ii) the dramatic decline in the risk of tuberculous infection from 1950 in England and Wales accelerated the decline in morbidity among all individuals, even among the older age groups with a high prevalence of tuberculous infection. We conclude that the risk of infection is the single most important factor affecting the magnitude of the tuberculous morbidity in a population, as it determines both the age pattern of initial infection (and hence the risk of developing disease) and the risk of reinfection. AD - Department of Epidemiology and Population Sciences, London School of Hygiene & Tropical Medicine, UK. AN - 9363017 AU - Vynnycky, E. AU - Fine, P. E. KW - Adolescent Adult Age Distribution Age of Onset Aged Child Child, Preschool Disease Progression England/epidemiology Human Incidence Infant Male Middle Age *Models, Statistical Morbidity Population Surveillance Recurrence Risk Factors Sensitivity and Specificity Support, Non-U.S. Gov't Time Factors Tuberculosis, Pulmonary/*epidemiology/*transmission Wales/epidemiology PY - 1997 RN - fulltext fulltext_1208 SP - 183-201. ST - The natural history of tuberculosis: the implications of age-dependent risks of disease and the role of reinfection T2 - Epidemiol Infect TI - The natural history of tuberculosis: the implications of age-dependent risks of disease and the role of reinfection UR - C:\users\rw\Papers\Vynnycky, Epi and Inf, 1997.pdfhttp://www.ncbi.nlm.nih.gov/pmc/articles/PMC2808840/pdf/9363017.pdf VL - 119 ID - 2351 ER - TY - JOUR AB - Tuberculosis (TB) was thought to be safely in decline in the United States in the mid-1980s because the number of cases had dropped by 74% between 1953 and 1985. An increase in TB cases was reported, however, in 1986, and an upward trend in TB incidence has continued. The turnaround in TB is well correlated with the rise of the HIV (human immunodeficiency virus) epidemic. The purpose of this work is to investigate, through the use of mathematical models, the magnitude and duration of the effect that the HIV epidemic may have on TB. Models are developed which reflect the transmission dynamics of both TB and HIV, and the relative merits of these models are discussed. The models are then linked together to form a model for the combined spread of both diseases. A numerical study is performed to investigate the influence of certain key parameters. The effect that HIV will have on the general population is found to be dependent on the contact structure between the general population and the HIV risk groups, as well as a possible shift in the dynamics associated with TB transmission. AD - Department of Statistics, University of South Carolina, Columbia 29208, USA. AN - 9198358 AU - West, R. W. AU - Thompson, J. R. DA - Jul 1 DO - S0025556497000011 [pii] DP - Nlm ET - 07/01 KW - AIDS-Related Opportunistic Infections/ epidemiology/transmission Forecasting Humans Models, Statistical Numerical Analysis, Computer-Assisted Population Surveillance Reproducibility of Results Risk Factors Tuberculosis/ epidemiology/transmission United States/epidemiology LA - eng N1 - West, R W Thompson, J R United states Mathematical biosciences Math Biosci. 1997 Jul 1;143(1):35-60. PY - 1997 RN - fulltext fulltext_1208 SN - 0025-5564 (Print) 0025-5564 (Linking) SP - 35-60 ST - Modeling the impact of HIV on the spread of tuberculosis in the United States T2 - Math Biosci TI - Modeling the impact of HIV on the spread of tuberculosis in the United States VL - 143 ID - 2352 ER - TY - JOUR AB - Epidemic control strategies alter the competitive dynamics between drug-sensitive and drug-resistant pathogens. In this paper, we describe and discuss a mathematical model that can be used to understand, and to predict, the effects of epidemic control strategies on both drug-sensitive and drug-resistant Mycobacterium tuberculosis. We begin by briefly reviewing the structure of the model. We then present new analytical results, and show how these results can be used: (i) to predict the epidemiological outcomes of epidemic control strategies an (ii) to design epidemic control strategies. We also include two new factors in our epidemic control models (reinfection and treatment delay); we discuss the epidemiological consequences of these two factors in the design of control strategies. Finally, we conclude with a brief discussion of the implications of our theoretical results for tuberculosis control in light of recently reported results from the WHO's Global Project on Anti-tuberculosis Drug Resistance Surveillance. AD - Univ Calif San Francisco, Dept Microbiol & Immunol, San Francisco, CA 94143 USA AN - WOS:000080857400005 AU - Blower, S. AU - Porco, T. AU - Lietman, T. J2 - Innov Appl Math LA - English N1 - Bn14a Times Cited:4 Cited References Count:28 Innovations in Applied Mathematics PY - 1998 SP - 51-72 ST - Tuberculosis: The evolution of antibiotic resistance and the design of epidemic control strategies T2 - Mathematical Models in Medical and Health Science TI - Tuberculosis: The evolution of antibiotic resistance and the design of epidemic control strategies UR - ://WOS:000080857400005 ID - 4830 ER - TY - JOUR AB - The high prevalence of tuberculosis in developing countries and the recent resurgence of tuberculosis in many developed countries suggests that current control strategies are suboptimal. The increase in drug-resistant cases exacerbates the control problems. Currently employed epidemic control strategies are not devised on the basis of a theoretical understanding of the transmission dynamics of Mycobacterium tuberculosis. We describe and discuss a theoretical framework based upon mathematical transmission models that can be used for understanding, predicting, and controlling tuberculosis epidemics. We illustrate how the theoretical framework can be used to predict the temporal dynamics of the emergence of drug resistance, to predict the epidemiological consequences of epidemic control strategies in developing and developed countries, and to design epidemic control strategies. AD - Department of Microbiology and Immunology, University of California San Francisco, 94143, USA. AN - 9725765 AU - Blower, S. M. AU - Gerberding, J. L. DA - Aug DP - Nlm ET - 09/02 KW - Disease Outbreaks Drug Resistance, Microbial Health Policy Humans Models, Biological Mycobacterium tuberculosis Tuberculosis/epidemiology/microbiology/ prevention & control LA - eng N1 - Blower, S M Gerberding, J L Research Support, U.S. Gov't, P.H.S. Review Germany Journal of molecular medicine (Berlin, Germany) J Mol Med (Berl). 1998 Aug;76(9):624-36. PY - 1998 RN - fulltext fulltext_1208 SN - 0946-2716 (Print) 0946-2716 (Linking) SP - 624-36 ST - Understanding, predicting and controlling the emergence of drug-resistant tuberculosis: a theoretical framework T2 - J Mol Med (Berl) TI - Understanding, predicting and controlling the emergence of drug-resistant tuberculosis: a theoretical framework VL - 76 ID - 2353 ER - TY - JOUR AB - This article focuses on the study of an age-structure model for the disease transmission dynamics of tuberculosis in populations that are subjected to a vaccination program. We first show that the infection-free steady state is globally stable if the basic reproductive number R0 is below one, and that an endemic steady state exists when the reproductive number in the presence of vaccine is above one. We then apply the theoretical results to vaccination policies to determine the optimal age or ages at which an individual should be vaccinated. It is shown that the optimal strategies can be either one- or two-age strategies. AD - Biometrics Unit, Cornell University, Ithaca, NY 14853, USA. AN - 9711046 AU - Castillo-Chavez, C. AU - Feng, Z. DA - Aug 1 ET - 08/26 J2 - Mathematical biosciences KW - Age Distribution *BCG Vaccine Health Policy Humans *Models, Biological Prevalence Public Health Tuberculosis/epidemiology/*prevention & control/transmission *Vaccination World Health LA - eng M3 - Research Support, U.S. Gov't, Non-P.H.S. N1 - Castillo-Chavez, C Feng, Z Math Biosci. 1998 Aug 1;151(2):135-54. PY - 1998 RN - fulltext fulltext_1208 SN - 0025-5564 (Print) 0025-5564 (Linking) SP - 135-54 ST - Global stability of an age-structure model for TB and its applications to optimal vaccination strategies T2 - Math Biosci TI - Global stability of an age-structure model for TB and its applications to optimal vaccination strategies UR - http://www.ncbi.nlm.nih.gov/pubmed/9711046http://www.sciencedirect.com/science/article/pii/S0025556498100160 VL - 151 ID - 2354 ER - TY - JOUR AB - BACKGROUND: WHO advocates the use of directly observed treatment with a short-course drug regimen as part of the DOTS strategy, but the potential effect of this strategy worldwide has not been investigated. METHODS: We developed an age-structured mathematical model to explore the characteristics of tuberculosis control under DOTS, and to forecast the effect of improved case finding and cure on tuberculosis epidemics for each of the six WHO regions. FINDINGS: In countries where the incidence of tuberculosis is stable and HIV-1 absent, a control programme that reaches the WHO targets of 70% case detection and 85% cure would reduce the incidence rate by 11% (range 8-12) per year and the death rate by 12% (9-13) per year. If tuberculosis has been in decline for some years, the same case detection and cure rates would have a smaller effect on incidence. DOTS saves a greater proportion of deaths than cases, and this difference is bigger in the presence of HIV-1. HIV-1 epidemics cause an increase in tuberculosis incidence, but do not substantially reduce the preventable proportion of cases and deaths. Without greater effort to control tuberculosis, the annual incidence of the disease is expected to increase by 41% (21-61) between 1998 and 2020 (from 7.4 million to 10.6 million cases per year). Achievement of WHO targets by 2010 would prevent 23% (15-30) or 48 million cases by 2020. INTERPRETATION: The potential effect of chemotherapy (delivered as DOTS) on tuberculosis is greater in many developing countries now than it was in developed countries 50 years ago. To exploit this potential, case detection and cure rates urgently need to be improved in the main endemic areas. AD - Global Tuberculosis Programme, WHO, Geneva, Switzerland. dyec@who.ch AN - 9863786 AU - Dye, C. AU - Garnett, G. P. AU - Sleeman, K. AU - Williams, B. G. DA - Dec 12 DO - S0140673698031997 [pii] DP - Nlm ET - 12/24 KW - Communicable Disease Control Developing Countries Europe/epidemiology HIV Infections/epidemiology Health Priorities Humans Incidence Models, Theoretical Netherlands/epidemiology Sensitivity and Specificity Tuberculosis/epidemiology/ prevention & control World Health Organization L1 - internal-pdf://0321645842/1-s2.0-S0140673698031997-main.pdf LA - eng N1 - Dye, C Garnett, G P Sleeman, K Williams, B G England Lancet Lancet. 1998 Dec 12;352(9144):1886-91. PY - 1998 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 0140-6736 (Print) 0140-6736 (Linking) SP - 1886-91 ST - Prospects for worldwide tuberculosis control under the WHO DOTS strategy. Directly observed short-course therapy T2 - Lancet TI - Prospects for worldwide tuberculosis control under the WHO DOTS strategy. Directly observed short-course therapy UR - http://ac.els-cdn.com/S0140673698031997/1-s2.0-S0140673698031997-main.pdf?_tid=28243448b090057ef68206195322d939&acdnat=1345104104_a8557f9be98cd1c666ed199d7693b80f VL - 352 ID - 2355 ER - TY - JOUR AB - OBJECTIVES: To evaluate the relative efficacy of personal respiratory protection as the concentrations of infectious aerosols increase or as room ventilation rates decrease. METHODS: We modified the Wells-Riley mathematical model of airborne transmission of disease by adding a variable for respirator leakage. We modeled three categories of infectiousness using various room ventilation rates and classes of respirators over a 10-hour exposure period. RESULTS: The risk of infection decreases exponentially with increasing room ventilation or with increasing personal respiratory protection. The relative efficacy of personal respiratory protection decreases as room ventilation rates increase or as the concentrations of infectious aerosols decrease. CONCLUSIONS: These modeling data suggest that the risk of occupational tuberculosis probably can be lowered considerably by using relatively simple respirators combined with modest room ventilation rates for the infectious aerosols likely to be present in isolation rooms of newly diagnosed patients. However, more sophisticated respirators may be needed to achieve a comparable risk reduction for exposures to more highly concentrated aerosols, such as may be generated during cough-inducing procedures or autopsies involving infectious patients. There is probably minimal benefit to the use of respirators in well-ventilated isolation rooms with patients receiving appropriate therapy. AD - National Jewish Medical and Research Center and the University of Colorado Health Sciences Center, Denver 80206, USA. fennelly.kevin@njrc.org AN - 9801283 AU - Fennelly, K. P. AU - Nardell, E. A. DA - Oct DP - Nlm ET - 11/04 KW - Air Microbiology Hospitals Humans Infection Control/ standards Occupational Diseases/etiology/ prevention & control Occupational Exposure/ adverse effects Patient Isolation Respiratory Protective Devices/utilization Tuberculosis, Pulmonary/etiology/ prevention & control United States Ventilation LA - eng N1 - Fennelly, K P Nardell, E A U50/CCU810073/PHS HHS/United States Research Support, U.S. Gov't, P.H.S. United states Infection control and hospital epidemiology : the official journal of the Society of Hospital Epidemiologists of America Infect Control Hosp Epidemiol. 1998 Oct;19(10):754-9. PY - 1998 RN - fulltext fulltext_1208 SN - 0899-823X (Print) 0899-823X (Linking) SP - 754-9 ST - The relative efficacy of respirators and room ventilation in preventing occupational tuberculosis T2 - Infect Control Hosp Epidemiol TI - The relative efficacy of respirators and room ventilation in preventing occupational tuberculosis VL - 19 ID - 2356 ER - TY - JOUR AB - Exposure of populations to microbes which share antigens with pathogens can influence the apparent efficacy of vaccines. This may explain the great variation (from below 0 to 80%) observed in protection by Bacillus Calmette Guerin (BCG) against tuberculosis. This paper explores three models for the effect of such heterologous immunity, and demonstrates that: (a) if the immune responses to the microbial antigens in nature and in the vaccines differ qualitatively, there will be no effect on observed efficacy; (b) if the immune responses differ only quantitatively, the observed vaccine efficacy will be reduced, and it will be minimal when vaccine-induced and heterologous protection are of similar magnitude; and (c) if the heterologous exposure can block the vaccine action, then observed efficacy will be reduced and may even appear negative. These results provide important guidance for the interpretation of BCG's utility and for the development and evaluation of new vaccines, in particular against tuberculosis. AD - Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, UK. pfine@lshtm.ac.uk AN - 9796044 AU - Fine, P. E. AU - Vynnycky, E. KW - Antibodies, Bacterial/biosynthesis Antibodies, Heterophile/biosynthesis Antigens, Heterophile/*immunology BCG Vaccine/*immunology Environmental Exposure Human Models, Biological Mycobacterium/*immunology Support, Non-U.S. Gov't Treatment Outcome Tuberculosis/prevention & control PY - 1998 RN - fulltext fulltext_1208 SP - 1923-8. ST - The effect of heterologous immunity upon the apparent efficacy of (e.g. BCG) vaccines T2 - Vaccine TI - The effect of heterologous immunity upon the apparent efficacy of (e.g. BCG) vaccines UR - http://www.ncbi.nlm.nih.gov/htbin-post/Entrez/query?db=m&form=6&dopt=r&uid=9796044 VL - 16 ID - 2357 ER - TY - JOUR AB - OBJECTIVES: This study tested the hypothesis, first proposed by Chaussinand, that individual-level immunity acquired from exposure to tuberculosis may have contributed to the disappearance of leprosy from western Europe. METHODS: The epidemiological consequences of cross-immunity were assessed by the formulation of a mathematical model of the transmission dynamics of tuberculosis and leprosy. RESULTS: The conditions under which Mycobacterium tuberculosis could have eradicated Mycobacterium leprae were derived in terms of the basic reproductive rates of the two infections and the degree of cross-immunity. CONCLUSIONS: If the degree of cross-immunity between two diseases within an individual is known, then the epidemiological consequences of this cross-immunity can be assessed with transmission modeling. The results of this analysis, in combination with previous estimates of the basic reproductive rate of tuberculosis and degree of cross-immunity, imply that tuberculosis could have contributed to the decline of leprosy if the basic reproductive rate of leprosy was low. AD - University of California, San Francisco, USA. AN - 9431277 AU - Lietman, T. AU - Porco, T. AU - Blower, S. DA - Dec DP - Nlm ET - 02/07 KW - Cause of Death Comorbidity Cross Reactions Disease Progression Europe Humans Immunity, Active Incidence Leprosy/epidemiology/immunology/transmission Models, Statistical Reproducibility of Results Time Factors Tuberculosis/epidemiology/immunology/transmission LA - eng N1 - Lietman, T Porco, T Blower, S United states American journal of public health Am J Public Health. 1997 Dec;87(12):1923-7. PY - 1998 RN - fulltext fulltext_1208 SN - 0090-0036 (Print) 0090-0036 (Linking) SP - 1923-7 ST - Leprosy and tuberculosis: the epidemiological consequences of cross-immunity T2 - Am J Public Health TI - Leprosy and tuberculosis: the epidemiological consequences of cross-immunity VL - 87 ID - 2344 ER - TY - JOUR AB - SETTING: Patient non-compliance and/or spatial heterogeneity in drug concentration or effectiveness may contribute to the emergence of drug resistance during multiple-drug chemotherapy of tuberculosis. OBJECTIVE: Using mathematical models of mycobacterial population dynamics under antimicrobial treatment, to assess the effects of non-compliance, heterogeneity and other factors on the success of treatment. DESIGN: A mathematical model is used to generate predictions about the ascent of drug resistance in treated hosts with non-compliance and/or a 'protected compartment' of bacteria where only one drug is active; simulations of a more realistic version of this model take into account random mutation, and different assumptions about the size of, and growth rate of bacteria in, the protected compartment. RESULTS: The existence of a protected compartment can increase the likelihood of resistance to the single drug active in that compartment, but only if bacteria resistant to that drug can grow in the protected compartment or if the host is non-adherent to the treatment regimen. However, the protected compartment may also slow the ascent of bacteria resistant to drugs not active in it (e.g. isoniazid) by providing a reservoir of non-selected mycobacteria. The model predicts that relative rates of killing are more important than mutation rates in determining the order in which resistant mutants ascend. Model predictions, in combination with data about drug resistance patterns, suggest that non-compliance, but not heterogeneity, is an important cause of treatment failure. CONCLUSION: Patterns of acquired drug resistance may be used to infer processes of selection during treatment; mathematical models can aid in generating predictions about the relative impacts of treatment parameters in the evolution of resistance, and eventually in suggesting improved treatment protocols. AD - Department of Biology, Emory University, Atlanta, Georgia, USA. lipsitch@biology.emory.edu AN - 9526190 AU - Lipsitch, M. AU - Levin, B. R. DA - Mar DP - Nlm ET - 04/04 KW - Antitubercular Agents/ pharmacology Drug Resistance, Microbial Drug Resistance, Multiple Humans Mathematics Models, Theoretical Mutation Mycobacterium tuberculosis/ drug effects/genetics Population Dynamics Treatment Refusal Tuberculosis/drug therapy L1 - internal-pdf://3214225008/s4.pdf.crdownload LA - eng N1 - Lipsitch, M Levin, B R PY - 1998 RN - fulltext fulltext_1208 SN - 1027-3719 (Print) 1027-3719 (Linking) SP - 187-99 ST - Population dynamics of tuberculosis treatment: mathematical models of the roles of non-compliance and bacterial heterogeneity in the evolution of drug resistance T2 - Int J Tuberc Lung Dis TI - Population dynamics of tuberculosis treatment: mathematical models of the roles of non-compliance and bacterial heterogeneity in the evolution of drug resistance VL - 2 ID - 2358 ER - TY - JOUR AB - An epidemiological model of tuberculosis has been developed and applied to five regions of the world. Globally, 6.7 million new cases of tuberculosis and 2.4 million deaths from tuberculosis are estimated for 1998. Based on current trends in uptake of the World Health Organization's strategy of directly observed treatment, short-course, we expect a total of 225 million new cases and 79 million deaths from tuberculosis between 1998 and 2030. Active case-finding by using mass miniature radiography could save 23 million lives over this period. A single contact treatment for tuberculosis could avert 24 million cases and 11 million deaths; combined with active screening, it could reduce mortality by nearly 40%. A new vaccine with 50% efficacy could lower incidence by 36 million cases and mortality by 9 million deaths. Support for major extensions to global tuberculosis control strategies will occur only if the size of the problem and the potential for action are recognized more widely. AD - Center for Population and Development Studies, Harvard School of Public Health, 9 Bow Street, Cambridge, MA 02138, USA. AN - 9811895 AU - Murray, C. J. AU - Salomon, J. A. DA - Nov 10 DP - Nlm ET - 11/13 KW - Communicable Disease Control Humans Models, Biological Models, Theoretical Tuberculosis/ epidemiology/ prevention & control World Health Organization LA - eng N1 - Murray, C J Salomon, J A United states Proceedings of the National Academy of Sciences of the United States of America Proc Natl Acad Sci U S A. 1998 Nov 10;95(23):13881-6. PY - 1998 RN - fulltext fulltext_1208 SN - 0027-8424 (Print) 0027-8424 (Linking) SP - 13881-6 ST - Modeling the impact of global tuberculosis control strategies T2 - Proc Natl Acad Sci U S A TI - Modeling the impact of global tuberculosis control strategies UR - http://www.pnas.org/content/95/23/13881.full.pdf VL - 95 ID - 2359 ER - TY - JOUR AD - Harvard Center for Population and Development Studies, Cambridge, Massachusetts 02138, USA. AN - 9755959 AU - Murray, C. J. AU - Salomon, J. A. DA - Sep ET - 10/02 J2 - The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease KW - Cost-Benefit Analysis Humans Models, Theoretical Tuberculosis, Pulmonary/epidemiology/*prevention & control World Health *World Health Organization LA - eng N1 - Murray, C J Salomon, J A FRANCE Int J Tuberc Lung Dis. 1998 Sep;2(9 Suppl 1):S9-15. PY - 1998 RN - fulltext fulltext_1208 SN - 1027-3719 (Print) 1027-3719 (Linking) SP - S9-15 ST - Expanding the WHO tuberculosis control strategy: rethinking the role of active case-finding T2 - Int J Tuberc Lung Dis TI - Expanding the WHO tuberculosis control strategy: rethinking the role of active case-finding UR - http://www.ncbi.nlm.nih.gov/pubmed/9755959 VL - 2 ID - 2360 ER - TY - JOUR AB - A hypothetical cohort of 25,000 TB patients and their contacts were followed for a 10-year period; rates of treatment default, infectiousness following partial treatment, relapse, hospitalization, and development of drug-resistant TB were included. The average cost per case cured was $16,846 with 15% of patients starting DOT, $17,323 with 100% starting DOT, and $20,106 with none starting DOT. The incremental cost per additional case cured was $24,064 when all patients, started treatment on DOT, indicating that outpatient DOT provides a cost-effective method of improving health outcomes for TB patients and their contacts while controlling direct costs. AD - MEDTAP International, Bethesda, MD, USA. AN - 10186738 AU - Palmer, C. S. AU - Miller, B. AU - Halpern, M. T. AU - Geiter, L. J. DA - May ET - 04/07 KW - Adult Ambulatory Care/*economics Bias (Epidemiology) Cost-Benefit Analysis *Decision Support Techniques Health Care Costs/*statistics & numerical data Health Services Research Humans Observation/*methods Outcome Assessment (Health Care) *Patient Compliance/psychology *Professional-Patient Relations Sensitivity and Specificity Treatment Failure Tuberculosis/*drug therapy/*economics/psychology United States L1 - internal-pdf://1171538998/Palmer-1998-A model of the cost-effectiveness.pdf LA - eng N1 - Palmer, C S Miller, B Halpern, M T Geiter, L J Comparative Study Research Support, U.S. Gov't, P.H.S. United states Journal of public health management and practice : JPHMP J Public Health Manag Pract. 1998 May;4(3):1-13. PY - 1998 RN - fulltext fulltext_1208 SN - 1078-4659 (Print) 1078-4659 (Linking) SP - 1-13 ST - A model of the cost-effectiveness of directly observed therapy for treatment of tuberculosis T2 - J Public Health Manag Pract TI - A model of the cost-effectiveness of directly observed therapy for treatment of tuberculosis UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=10186738 VL - 4 ID - 2361 ER - TY - JOUR AB - Previously we have formulated transmission models of untreated tuberculosis epidemics (Blower et al., Nature, Medicine 1 (1995), 815-821); in this paper, we present time-dependent uncertainty and sensitivity analyses in order to quantitatively understand the transmission dynamics of tuberculosis epidemics in the absence of treatment. The time-dependent uncertainty analysis enabled us to evaluate the variability in the epidemiological outcome variables of the model during the progression of a tuberculosis epidemic. Calculated values (from the uncertainty analysis) for the disease incidence, disease prevalence, and mortality rates were approximately consistent with historical data. The time-dependent sensitivity analysis revealed that only a few of the model's input parameters significantly affected the severity of a tuberculosis epidemic; these parameters were the disease reactivation rate, the fraction of infected individuals who develop tuberculosis soon after infection, the number of individuals that an infectious individual infects per year, the disease death rate, and the population recruitment rate. Our analysis demonstrates that it is possible to improve our understanding of the behavior of tuberculosis epidemics by applying time-dependent uncertainty and sensitivity analysis to a transmission model. AD - San Francisco Department of Public Health, 25 Van Ness Avenue, Suite 710, San Francisco, California, 94102, USA. travis_porco@dph.sf.ca.us AU - Porco, T. C. AU - Blower, S. M. DO - 10.1006/tpbi.1998.1366 KW - Disease Outbreaks/statistics & numerical data Humans Incidence Models, Biological Prevalence Sensitivity and Specificity Tuberculosis/epidemiology/mortality/transmission N1 - LR: 20071114; CI: Copyright 1998; GR: 1R29DA08153/DA/NIDA NIH HHS/United States; GR: AI33831/AI/NIAID NIH HHS/United States; JID: 0256422; ppublish PY - 1998 RN - fulltext fulltext_1208 SN - 0040-5809; 0040-5809 SP - 117-132 ST - Quantifying the intrinsic transmission dynamics of tuberculosis T2 - Theoretical population biology TI - Quantifying the intrinsic transmission dynamics of tuberculosis VL - 54 Y2 - Oct ID - 2362 ER - TY - JOUR AB - SETTING: A major out-patient tuberculosis clinic in Nairobi, Kenya. OBJECTIVE: To ascertain the cost-effectiveness of the polymerase chain reaction (PCR) for the diagnosis of tuberculosis in an urban setting in a developing country. DESIGN: A cost-effectiveness analysis of PCR and direct smear microscopy examination based on theoretical modelling. The cost-effectiveness was expressed in costs per correctly diagnosed tuberculosis patient for each of the two diagnostic techniques. Data were obtained from the literature, from the staff and the register at the health facility and from structured interviews with patients. Assumptions were made when no data were available. RESULTS: The PCR is expected to be more specific and sensitive than the routine procedure for diagnosis, but it is also more costly. The routine procedure based on direct smear microscopy turned out to be 1.8 times as cost-effective as PCR. CONCLUSION: It is concluded that the PCR method can potentially be a cost-effective screening procedure for tuberculosis, provided that the largest contributing cost component, the costs of the PCR-kit, can be reduced substantially. AD - Royal Tropical Institute, The Netherlands. AN - 9526197 AU - Roos, B. R. AU - van Cleeff, M. R. AU - Githui, W. A. AU - Kivihya-Ndugga, L. AU - Odhiambo, J. A. AU - Kibuga, D. K. AU - Klatser, P. R. DA - Mar DP - Nlm ET - 04/04 KW - Bacteriological Techniques/economics Cost-Benefit Analysis Humans Kenya Models, Theoretical Polymerase Chain Reaction/ economics Sensitivity and Specificity Sputum/ microbiology Tuberculosis, Pulmonary/ diagnosis LA - eng N1 - Roos, B R van Cleeff, M R Githui, W A Kivihya-Ndugga, L Odhiambo, J A Kibuga, D K Klatser, P R Comparative Study Research Support, Non-U.S. Gov't France The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease Int J Tuberc Lung Dis. 1998 Mar;2(3):235-41. PY - 1998 RN - fulltext fulltext_1208 SN - 1027-3719 (Print) 1027-3719 (Linking) SP - 235-41 ST - Cost-effectiveness of the polymerase chain reaction versus smear examination for the diagnosis of tuberculosis in Kenya: a theoretical model T2 - Int J Tuberc Lung Dis TI - Cost-effectiveness of the polymerase chain reaction versus smear examination for the diagnosis of tuberculosis in Kenya: a theoretical model VL - 2 ID - 2363 ER - TY - JOUR AB - BACKGROUND: Isoniazid prophylaxis for 12 months effectively prevents tuberculosis in HIV-infected persons and may decrease the incidence of other HIV-related disease and mortality. Recent clinical trials have found that some short-course regimens also effectively prevent tuberculosis. OBJECTIVE: To compare the benefits, risks, and cost-effectiveness of isoniazid prophylaxis and short-course prophylaxis regimens. DESIGN: Decision and cost-effectiveness analysis. SETTING: United States. PATIENTS: Hypothetical patients who are HIV-infected and have CD4 counts of 200 cells/mm3 or less and positive results on tuberculin skin tests. INTERVENTIONS: Isoniazid prophylaxis lasting 12 months and six short-course prophylaxis regimens of isoniazid, rifampin, and pyrazinamide alone or in combination. MEASUREMENTS: 5-year survival rate, life expectancy, lifetime incidence of tuberculosis, and cost per quality-adjusted life-year saved. RESULTS: Compared with no prophylaxis, the 12-month isoniazid regimen increased 5-year survival rates by 9% and life expectancy by 8.7 months, decreased incidence of tuberculosis by 27%, and saved 4 medical care dollars for every 1 spent on prophylaxis. Regimens of isoniazid for 6 months, isoniazid and rifampin for 3 months, and rifampin and pyrazinamide for 2 months had similar results: 6.2- to 8.6-month increases in life expectancy, 19% to 26% reductions in incidence of tuberculosis, and 1 to 7 medical care dollars saved for every 1 spent on prophylaxis. A 3-month regimen of isoniazid, rifampin, and pyrazinamide resulted in fewer clinical benefits and was the only regimen tested that did not save medical care dollars. CONCLUSIONS: Prophylaxis decreases the incidence of tuberculosis and increases life expectancy for HIV-infected patients. Some regimens save medical care dollars, and some short-course regimens have clinical and economic benefits similar to those of the 12-month isoniazid regimen. Short-course prophylaxis is a reasonable alternative to the 12-month isoniazid regimen. AD - Long Island Jewish Medical Center, New Hyde Park, New York 11042, USA. AN - 9841583 AU - Rose, D. N. DA - Nov 15 ET - 12/05 KW - AIDS-Related Opportunistic Infections/*prevention & control Antibiotics, Antitubercular/administration & dosage Antitubercular Agents/*administration & dosage/adverse effects/economics Cost-Benefit Analysis Decision Trees Drug Administration Schedule Drug Therapy, Combination Drug-Induced Liver Injury/etiology Humans Isoniazid/*administration & dosage/adverse effects/economics Pyrazinamide/administration & dosage Quality-Adjusted Life Years Rifampin/administration & dosage Survival Rate Tuberculosis/*prevention & control LA - eng N1 - Rose, D N United states Annals of internal medicine Ann Intern Med. 1998 Nov 15;129(10):779-86. PY - 1998 RN - fulltext fulltext_1208 SN - 0003-4819 (Print) 0003-4819 (Linking) SP - 779-86 ST - Short-course prophylaxis against tuberculosis in HIV-infected persons. A decision and cost-effectiveness analysis T2 - Ann Intern Med TI - Short-course prophylaxis against tuberculosis in HIV-infected persons. A decision and cost-effectiveness analysis UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=9841583http://annals.org/data/Journals/AIM/19920/0000605-199811150-00005.pdf VL - 129 ID - 2364 ER - TY - JOUR AB - The authors used epidemiologic data on tuberculosis to construct a model for the time delay from initial latent infection to active disease, when infection transmission occurs. They used case rate tables in the United States to calculate the fractional rate of change per annum (A) in the incidence of active tuberculosis. They then derived estimates for the effective reproductive number (R) and the cumulative transmission, defined as the number of people whom one infected person will infect in his or her lifetime and over many multiple successive transmissions, respectively. For A of -4 percent per year, the average US condition from 1930 to 1995, they estimate the reproductive number to be about 0.55 and the cumulative transmission to be about 1.2. The estimated rate of the new latent infections in the United States is 80,000 per year, the estimated prevalence of latent infections is 5 percent, and the number of transmissions of infection per active case is 3.5. From the model, the authors predicted active case rates in various age groups and compared them with published tables. The comparison suggests that the risk of activation decreases rapidly, then gradually, for the first 10 years after initial infection; the risk is relatively constant from 10 to 40 years and may decrease again after 40 years. The authors also discuss how this model can be used to help make decisions about tuberculosis control measures in the population. AD - Center for Radiophysics and Space Research, Cornell University, Ithaca, NY 14853, USA. AN - 9508108 AU - Salpeter, E. E. AU - Salpeter, S. R. DA - Feb 15 DP - Nlm ET - 03/21 KW - Age Distribution Humans Incidence Models, Theoretical Prevalence Prospective Studies Retrospective Studies Tuberculosis/ epidemiology/transmission United States/epidemiology LA - eng N1 - Salpeter, E E Salpeter, S R Research Support, Non-U.S. Gov't United states American journal of epidemiology Am J Epidemiol. 1998 Feb 15;147(4):398-406. PY - 1998 RN - fulltext fulltext_1208 SN - 0002-9262 (Print) 0002-9262 (Linking) SP - 398-406 ST - Mathematical model for the epidemiology of tuberculosis, with estimates of the reproductive number and infection-delay function T2 - Am J Epidemiol TI - Mathematical model for the epidemiology of tuberculosis, with estimates of the reproductive number and infection-delay function UR - http://aje.oxfordjournals.org/content/147/4/398.full.pdf VL - 147 ID - 2365 ER - TY - JOUR AU - Sawert, H. AU - Girardi, E. AU - Antonucci, G. AU - Raviglione, M. C. AU - Viale, P. AU - Ippolito, G. DA - 1998 KW - Antitubercular Agents/*economics/therapeutic use AIDS-Related Opportunistic Infections/*economics/microbiology/*prevention & control Cost-Benefit Analysis Human Isoniazid/*economics/therapeutic use Italy Life Expectancy Patient Compliance Prospective Studies Quality-Adjusted Life Years Support,Non-U.S.Gov't Survival Analysis Tuberculosis/*economics/etiology/*prevention & control LB - 451 N1 - RefMgr field[1]: Journal RefMgr field[8]: Not in File PY - 1998 RN - fulltext fulltext_1208 SP - 2112-2121 ST - Preventive therapy for tuberculosis in HIV-infected persons: analysis of policy options based on tuberculin status and CD4+ cell count. Gruppo Italiano di Studio Tubercolosi e AIDS (GISTA) T2 - Archives of Internal Medicine TI - Preventive therapy for tuberculosis in HIV-infected persons: analysis of policy options based on tuberculin status and CD4+ cell count. Gruppo Italiano di Studio Tubercolosi e AIDS (GISTA) UR - http://archinte.jamanetwork.com/article.aspx?articleid=210066 VL - 158 ID - 2366 ER - TY - JOUR AB - SETTING: England and Wales. OBJECTIVE: To estimate the magnitude and trend in the annual risk of infection with Mycobacterium tuberculosis in England and Wales since 1901. DESIGN: Estimates for the prechemotherapy era are derived assuming that 1% of new infections among 0-4 year olds led to fatal tuberculosis meningitis, as found in the Netherlands. The estimates are validated against data from the 1949-1950 national tuberculin survey. We explore the trend thereafter using tuberculous meningitis notifications and data from the 1971-1973 national tuberculin survey, and discuss the utility of data collected under the national bacille Calmette-Guerin (BCG) vaccination scheme for estimating the annual risk of infection. RESULTS: Tuberculosis meningitis mortality rates among 0-4 year olds declined at 4% per annum until 1950, and suggest that the annual risk of infection declined from 12% in 1901 to 1.9% in 1949. The decline in the annual risk of infection probably accelerated in 1950, although its magnitude cannot be determined accurately. CONCLUSION: An accelerated decline in the annual risk of infection in England and Wales from 1950 probably resulted from the introduction of chemotherapy, which dramatically reduced the prevalence of sources of infection in the population. Data collected during the national BCG vaccination scheme were found to be unsuitable for estimating infection risks. AD - Department of Epidemiology and Population Sciences, London School of Hygiene and Tropical Medicine, UK. AN - 9441091 AU - Vynnycky, E. AU - Fine, P. E. DA - Oct ET - 01/24 J2 - The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease KW - Adolescent Age Distribution BCG Vaccine/*administration & dosage Child Child, Preschool Data Collection England/epidemiology Female Humans Incidence Infant Male Mycobacterium tuberculosis/*immunology Risk Factors Sex Distribution Survival Rate Tuberculin/diagnostic use Tuberculosis, Meningeal/diagnosis/*epidemiology/*prevention & control Wales/epidemiology LA - eng M3 - Research Support, Non-U.S. Gov't N1 - Vynnycky, E Fine, P E FRANCE Int J Tuberc Lung Dis. 1997 Oct;1(5):389-96. PY - 1998 RN - fulltext fulltext_1208 SN - 1027-3719 (Print) 1027-3719 (Linking) SP - 389-96 ST - The annual risk of infection with Mycobacterium tuberculosis in England and Wales since 1901 T2 - Int J Tuberc Lung Dis TI - The annual risk of infection with Mycobacterium tuberculosis in England and Wales since 1901 UR - http://www.ncbi.nlm.nih.gov/pubmed/9441091 VL - 1 ID - 2350 ER - TY - JOUR AB - The net and basic reproduction numbers are among the most widely-applied concepts in infectious disease epidemiology. A net reproduction number (the average number of secondary infectious cases resulting from each case in a given population) of above 1 is conventionally associated with an increase in incidence; the basic reproduction number (defined analogously for a 'totally susceptible' population) provides a standard measure of the 'transmission potential' of an infection. Using a model of the epidemiology of tuberculosis in England and Wales since 1900, we demonstrate that these measures are difficult to apply if disease can follow reinfection, and that they lose their conventional interpretations if important epidemiological parameters, such as the rate of contact between individuals, change over the time interval between successive cases in a chain of transmission (the serial interval). The net reproduction number for tuberculosis in England and Wales appears to have been approximately 1 from 1900 until 1950, despite concurrent declines in morbidity and mortality rates, and it declined rapidly in the second half of this century. The basic reproduction number declined from about 3 in 1900, reached 2 by 1950, and first fell below 1 in about 1960. Reductions in effective contact between individuals over this period, measured in terms of the average number of individuals to whom each case could transmit the infection, meant that the conventional basic reproduction number measure (which does not consider subsequent changes in epidemiological parameters) for a given year failed to reflect the 'actual transmission potential' of the infection. This latter property is better described by a variant of the conventional measure which takes secular trends in contact into account. These results are relevant for the interpretation of trends in any infectious disease for which epidemiological parameters change over time periods comparable to the infectious period, incubation period or serial interval. AD - Department of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, England. AN - 9825782 AU - Vynnycky, E. AU - Fine, P. E. DA - Oct ET - 11/24 J2 - Epidemiology and infection KW - Adolescent Adult Aged Child Child, Preschool Disease Susceptibility/*epidemiology Disease Transmission, Infectious/statistics & numerical data England/epidemiology Epidemiologic Methods Female Humans Infant Infant, Newborn Male Middle Aged Risk Factors Time Factors Tuberculosis/*epidemiology Wales/epidemiology LA - eng M3 - Research Support, Non-U.S. Gov't N1 - Vynnycky, E Fine, P E ENGLAND Epidemiol Infect. 1998 Oct;121(2):309-24. PY - 1998 RN - fulltext fulltext_1208 SN - 0950-2688 (Print) 0950-2688 (Linking) SP - 309-24 ST - The long-term dynamics of tuberculosis and other diseases with long serial intervals: implications of and for changing reproduction numbers T2 - Epidemiol Infect TI - The long-term dynamics of tuberculosis and other diseases with long serial intervals: implications of and for changing reproduction numbers UR - http://www.ncbi.nlm.nih.gov/pubmed/9825782 VL - 121 ID - 2367 ER - TY - JOUR AU - Bell, J. C. AU - Rose, D. N. AU - Sacks, H. S. DA - 1999 KW - Africa control cost effectiveness HIV interventions NTP preventive therapy tuberculosis Preventive Therapy TB and HIV LB - 6488 N1 - TY - JOUR TB Intervention strategies Preventive chemotherapy No sub-heading PY - 1999 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SP - 1549-1556 ST - Tuberculosis preventive therapy for HIV-infected people in sub-Saharan Africa is cost-effective T2 - AIDS TI - Tuberculosis preventive therapy for HIV-infected people in sub-Saharan Africa is cost-effective UR - http://graphics.tx.ovid.com/ovftpdfs/FPDDNCDCLFEDDD00/fs046/ovft/live/gv023/00002030/00002030-199908200-00016.pdf VL - 13 ID - 2368 ER - TY - JOUR AB - The availability of DNA fingerprinting techniques for Mycobacterium tuberculosis has led to attempts to estimate the extent of recent transmission in populations, using the assumption that groups of tuberculosis patients with identical isolates ("clusters") are likely to reflect recently acquired infections. It is never possible to include all cases of tuberculosis in a given population in a study, and the proportion of isolates found to be clustered will depend on the completeness of the sampling. Using stochastic simulation models based on real and hypothetical populations, the authors demonstrate the influence of incomplete sampling on the estimates of clustering obtained. The results show that as the sampling fraction increases, the proportion of isolates identified as clustered also increases and the variance of the estimated proportion clustered decreases. Cluster size is also important: the underestimation of clustering for any given sampling fraction is greater, and the variability in the results obtained is larger, for populations with small clusters than for those with the same number of individuals arranged in large clusters. A considerable amount of caution should be used in interpreting the results of studies on clustering of M. tuberculosis isolates, particularly when sampling fractions are small. AD - Infectious Disease Epidemiology Unit, London School of Hygiene and Tropical Medicine, England, United Kingdom. AN - 10025480 AU - Glynn, J. R. AU - Vynnycky, E. AU - Fine, P. E. DA - Feb 15 ET - 02/20 J2 - American journal of epidemiology KW - Bias (Epidemiology) Cluster Analysis *DNA Fingerprinting Epidemiologic Methods Humans Models, Statistical Mycobacterium tuberculosis/*genetics Sampling Studies San Francisco South Africa Stochastic Processes Tuberculosis, Pulmonary/*transmission LA - eng M3 - Research Support, Non-U.S. Gov't N1 - Glynn, J R Vynnycky, E Fine, P E Am J Epidemiol. 1999 Feb 15;149(4):366-71. PY - 1999 RN - fulltext fulltext_1208 SN - 0002-9262 (Print) 0002-9262 (Linking) SP - 366-71 ST - Influence of sampling on estimates of clustering and recent transmission of Mycobacterium tuberculosis derived from DNA fingerprinting techniques T2 - Am J Epidemiol TI - Influence of sampling on estimates of clustering and recent transmission of Mycobacterium tuberculosis derived from DNA fingerprinting techniques UR - http://www.ncbi.nlm.nih.gov/pubmed/10025480http://aje.oxfordjournals.org/content/149/4/366.full.pdf VL - 149 ID - 2369 ER - TY - JOUR AB - Since 1985, there has been a renewed epidemic of tuberculosis (TB) that was previously thought to be in check. There is evidence to believe the main factor for this resurgence has been the human immunodeficiency virus (HIV). Co-infection with HIV and M. Tuberculosis has profound implications for the course of both diseases. This study represents a first attempt to understand how the introduction of an opportunistic infection, namely Mycobacterium tuberculosis, the bacteria that causes TB, affects the dynamic interaction of HIV-1 and the immune system. We create a mathematical model using ordinary differential equations to describe the interaction of HIV and TB with the immune system. It is known that infection with TB can decrease the CD4(+) T cell counts-a key marker of AIDS progression; thus, it shortens survival in HIV infected individuals. Another main marker for HIV progression is the viral load. If this load is increased due to the presence of opportunistic infections, the disease progression is much more rapid. We also explore the effects of drug treatment on the TB infection in the doubly-infected patient. AD - Department of Microbiology and Immunology, The University of Michigan Medical School, 6730 Medical Science Building II, Ann Arbor, Michigan, 48109-0620, USA. AN - 9925811 AU - Kirschner, D. DA - Feb DO - S0040-5809(98)91382-X [pii] 10.1006/tpbi.1998.1382 [doi] DP - Nlm ET - 02/02 KW - AIDS-Related Opportunistic Infections/ immunology/mortality CD4 Lymphocyte Count Disease Progression HIV-1/ immunology Humans Macrophages/immunology Models, Immunological Models, Theoretical Mycobacterium tuberculosis/ immunology Survival Rate Tuberculosis, Pulmonary/ immunology/mortality Viral Load LA - eng N1 - Kirschner, D United states Theoretical population biology Theor Popul Biol. 1999 Feb;55(1):94-109. PY - 1999 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 0040-5809 (Print) 0040-5809 (Linking) SP - 94-109 ST - Dynamics of co-infection with M. Tuberculosis and HIV-1 T2 - Theor Popul Biol TI - Dynamics of co-infection with M. Tuberculosis and HIV-1 UR - http://ac.els-cdn.com/S004058099891382X/1-s2.0-S004058099891382X-main.pdf?_tid=189b89f5729a64420cd0d53151ea421c&acdnat=1345012541_8bb51f37ee63fbdd230b9d23f406634c VL - 55 ID - 2370 ER - TY - JOUR AU - Marchand, R. AU - Tousignant, P. AU - Chang, H. DA - 1999 J2 - Int.J.Epidemiol. KW - case-finding cost effectiveness elderly infection institutions screening tuberculin testing tuberculosis LB - 9035 N1 - TY - JOUR TB Tuberculosis control Case-finding No sub-heading PY - 1999 RN - fulltext fulltext_1208 SP - 563-570 ST - Cost-effectiveness of screening compared to case-finding approaches to tuberculosis in long-term care facilities for the elderly T2 - International Journal of Epidemiology TI - Cost-effectiveness of screening compared to case-finding approaches to tuberculosis in long-term care facilities for the elderly VL - 28 ID - 2371 ER - TY - JOUR AB - We assessed the direct and indirect economic costs and benefits of the current policy of revaccinating tuberculin-negative schoolchildren in the Czech Republic. The analysis is conducted from the perspective of the payer for health care. In considering whether revaccination should be discontinued, we consistently made assumptions which tend to favor revaccination. The direct costs of revaccination are estimated at Czech Koruna (KCR) 15.0 million (US$0.46 million) annually. The direct benefits are the treatment costs saved for future cases averted by revaccination. These range from KCR 0.5 million (US$0.015 million, ambulatory care, excluding transmission benefits) to KCR 13.7 million (US$0.4 million, hospitalization, including transmission benefits). Costs exceed benefits even if children are revaccinated without prior tuberculin testing. The major indirect cost is the loss of work output attributable to tuberculosis morbidity. Counting the averted loss in output as a benefit does not change the results qualitatively, although there is a 50% chance that the benefits will be greater than costs if treatment continues to be hospital-based. Thus, the costs of revaccination in the Czech Republic are found to exceed benefits over most, plausible variations in parameter values. The cost-benefit ratio is especially large if patients are given ambulatory treatment, as recommended by the World Health Organization. AD - Department of Health Systems, World Health Organization, Geneva, Switzerland. AN - 10217591 AU - Pathania, V. S. AU - Trnka, L. AU - Krejbich, F. AU - Dye, C. DA - Apr 9 KW - Ambulatory Care/economics BCG Vaccine/*economics/immunology Child Cohort Studies Cost of Illness Cost-Benefit Analysis Czech Republic/epidemiology Health Care Costs Hospitalization/economics Human Immunization Schedule Incidence Insurance, Health/economics Life Expectancy Multivariate Analysis Time Factors Treatment Outcome Tuberculin Test/economics Tuberculosis/economics/epidemiology/immunology/*prevention & control Vaccination/*economics World Health Organization N1 - 99231943 0264-410x Journal Article PY - 1999 RN - fulltext fulltext_1208 SP - 1926-1935 ST - A cost-benefit analysis of BCG revaccination in the Czech Republic T2 - Vaccine TI - A cost-benefit analysis of BCG revaccination in the Czech Republic UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=10217591 VL - 17 ID - 2372 ER - TY - JOUR AB - To determine the incremental cost of directly observed therapy (DOT) for patients with tuberculosis at low risk for treatment default, we applied a model of DOT effectiveness to 1,377 low-risk patients in California during 1995. The default rate for this cohort, which consisted of those with no recent history of substance abuse, homelessness, or incarceration, was 1.7%. The model predicted that DOT and self-administered therapy (SAT) cured 93.1 and 90.8% of these patients, respectively. DOT would initially cost $1.83 million more than SAT, but avert $569,191 in treatment cost for relapse cases and their contacts, for a net incremental cost of $1.27 million ($919 per patient treated), or $40,620 per additional case cured. The cost-effectiveness of DOT was sensitive to the default rate and relapse rate after completing SAT. DOT would generate cost savings only when the default and relapse rates were more than 32.2 and 9.2%, respectively. Given the low default rate and resulting high incremental cost of DOT, provision of DOT to low-risk patients in California should be evaluated in the context of resource availability, competing program priorities, and program success in completing self-administered therapy with a low relapse rate. AD - California Department of Health Services, Tuberculosis Control Branch, Berkeley, CA, USA. AN - 10430732 AU - Snyder, D. C. AU - Chin, D. P. DA - Aug ET - 08/03 KW - Adult Antitubercular Agents/*economics/therapeutic use California Cost-Benefit Analysis Female Health Resources/economics Humans Male Outcome and Process Assessment (Health Care) *Patient Compliance Patient Dropouts Recurrence Risk Self Administration/economics Tuberculosis, Pulmonary/drug therapy/*economics LA - eng N1 - Snyder, D C Chin, D P Comparative Study United states American journal of respiratory and critical care medicine Am J Respir Crit Care Med. 1999 Aug;160(2):582-6. PY - 1999 RN - fulltext fulltext_1208 SN - 1073-449X (Print) 1073-449X (Linking) SP - 582-6 ST - Cost-effectiveness analysis of directly observed therapy for patients with tuberculosis at low risk for treatment default T2 - Am J Respir Crit Care Med TI - Cost-effectiveness analysis of directly observed therapy for patients with tuberculosis at low risk for treatment default UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=10430732 VL - 160 ID - 2373 ER - TY - JOUR AU - Snyder, D. C. AU - Paz, E. A. AU - Mohle-Boetani, J. C. AU - Fallstad, R. AU - Black, R. L. AU - Chin, D. P. DA - 1999 J2 - Am.J.Respir.Crit.Care Med. KW - cost effectiveness effectiveness interventions methadone prevention preventive therapy screening substance abuse tuberculosis LB - 6572 N1 - TY - JOUR TB Intervention strategies Preventive chemotherapy No sub-heading PY - 1999 RN - fulltext fulltext_1208 SP - 178-185 ST - Tuberculosis prevention in methadone maintenance clinics. Effectiveness and cost-effectiveness TI - Tuberculosis prevention in methadone maintenance clinics. Effectiveness and cost-effectiveness VL - 160 ID - 2374 ER - TY - JOUR AB - BACKGROUND: The dramatic decline in tuberculosis (TB) in developed countries during the past century has been attributed to many factors, including improvements in living and social conditions and, more recently, effective treatment. Each of these changes should have reduced the average number of individuals 'effectively contacted' (i.e. sufficiently to transmit infection) by each infectious TB case. METHOD: Estimates of the average number of individuals effectively contacted by each infectious TB case, for each year since 1900 in England and Wales, are derived as the ratio between published estimates of the annual risk of infection and estimates of the prevalence of infectious cases, as derived using a published model of the epidemiology of TB. RESULTS: The results suggest that each infectious case contacted, on average, about 22 individuals in 1900 sufficiently to transmit Mycobacterium tuberculosis infection, and that this number declined to about 10 by 1950 and to approximately one by 1990. CONCLUSIONS: Although several factors contributed to the decline in TB in developed countries during this century, a major contributor has been the decline in the number of effective contacts by each case over time. Similar declines have doubtless occurred over the past century for many infections in developed countries. AD - Department of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, UK. AN - 10342699 AU - Vynnycky, E. AU - Fine, P. E. DA - Apr ET - 05/26 J2 - International journal of epidemiology KW - Adolescent Adult Age Distribution Aged Child Child, Preschool Contact Tracing/*trends Disease Transmission, Infectious/*prevention & control Female Great Britain/epidemiology Humans Male Middle Aged Models, Statistical Population Surveillance Prevalence Reproducibility of Results Risk Factors Sex Distribution Survival Rate Tuberculosis, Pulmonary/*epidemiology/*transmission LA - eng M3 - Research Support, Non-U.S. Gov't N1 - Vynnycky, E Fine, P E ENGLAND Int J Epidemiol. 1999 Apr;28(2):327-34. PY - 1999 RN - fulltext fulltext_1208 SN - 0300-5771 (Print) 0300-5771 (Linking) SP - 327-34 ST - Interpreting the decline in tuberculosis: the role of secular trends in effective contact T2 - Int J Epidemiol TI - Interpreting the decline in tuberculosis: the role of secular trends in effective contact UR - http://www.ncbi.nlm.nih.gov/pubmed/10342699http://ije.oxfordjournals.org/content/28/2/327.full.pdf VL - 28 ID - 2375 ER - TY - JOUR AB - Adherence to therapy in patients with tuberculosis (TB) is a major determinant of their outcomes. Unfortunately, there are no currently known predictors of adherence, given that this phenomenon represents a complex, task-specific behavior. Notwithstanding criticisms from civil liberty advocates, directly observed therapy (DOT), facilitated by education, holistic care, enablers and incentives, is still the best strategy to ensure patient adherence to treatment. To enhance delivery of DOT, short-course chemotherapy (SCC) must be strongly advocated. Monitoring of patient progress, dependable drug supply, and adequate programme funding are other important elements of the entire strategy. Indeed, since the global resurgence of TB and associated rampant drug resistance in the 1990s, directly observed therapy, short-course (DOTS) has now become the WHO strategy for effective TB control. Data obtained so far in different continents worldwide have underscored the unrivalled efficacy of DOTS in ensuring treatment success and preventing development of acquired drug resistance. The recent WHO/International Union against Tuberculosis and Lung Disease (IUATLD) global project on anti-TB drug resistance surveillance has also revealed that countries in which >33-90% of the population has access to the WHO DOTS strategy have, as a group, lower levels of drug resistance: primary multidrug-resistant (MDR) (1.4%; median) and acquired MDR index (0. 6; median). The use of SCC was also inversely associated with the prevalence of combined resistance to any drug. Countries with MDR rates >2% reported using SCC in a median of 70% of their patients, compared with 100% in countries with MDR rates <2% (WHO/TB/97.229). Despite greater initial cost, DOTS is a more cost-effective strategy than self-administered therapy because it decreases the re-treatment costs associated with therapy failure and acquired drug resistance. Finally, in addition to harnessing the complementary roles of a national tuberculosis programme and community participation, DOTS might be further enhanced by the use of newly developed drugs with a long duration of action or more potent bactericidal and sterilizing activities. AD - Tuberculosis and Chest Unit, Grantham Hospital, Hong Kong, China. AN - 10449895 AU - Yew, W. W. DO - 48479 DP - Nlm ET - 08/18 J2 - Chemotherapy KW - Antitubercular Agents/ administration & dosage Drug Administration Schedule Humans International Cooperation Monitoring, Physiologic Patient Advocacy Patient Compliance Physician-Patient Relations Tuberculosis, Multidrug-Resistant/ drug therapy/prevention & control Tuberculosis, Pulmonary/ drug therapy/prevention & control World Health LA - eng N1 - Yew, W W Switzerland Chemotherapy. 1999;45 Suppl 2:26-33. PY - 1999 RN - fulltext fulltext_1208 SN - 0009-3157 (Print) 0009-3157 (Linking) SP - 26-33 ST - Directly observed therapy, short-course: the best way to prevent multidrug-resistant tuberculosis T2 - Chemotherapy TI - Directly observed therapy, short-course: the best way to prevent multidrug-resistant tuberculosis VL - 45 Suppl 2 ID - 2376 ER - TY - JOUR AU - Aparicio, J. P. AU - Capurro, A. F. AU - Castillo-Chavez, C. DA - 2000 KW - airborne contacts infection models transmission tuberculosis LB - 8135 N1 - TY - JOUR TB Transmission, pathogenesis, and epidemiology Infection with tubercle bacilli Etiol epi: RF for infection Transmission - airborne PY - 2000 RN - fulltext fulltext_1208 SP - 327-341 ST - Transmission and dynamics of tuberculosis on generalized households T2 - J.Theor.Biol. TI - Transmission and dynamics of tuberculosis on generalized households VL - 206 ID - 2377 ER - TY - JOUR AB - SETTING: From 1958 to 1978, Baltimore maintained one of the highest pulmonary tuberculosis (TB) rates in the US. But, from 1978 to 1992 its TB rate declined by 64.3% and its ranking for TB fell from second highest among large US cites to twenty-eighth. This TB trend coincided with the implementation of an aggressive directly observed therapy (DOT) program by Baltimore's Health Department. OBJECTIVES: We used modeling to estimate the range of TB cases prevented in Baltimore under DOT. Case estimates equal the difference between the observed number of TB cases in Baltimore versus the expected number if Baltimore's TB trend was replaced by the TB trend for the US (low estimate) or the TB trend for all US cities with over 250,000 residents (high estimate). Economic savings are estimated. RESULTS: Without DOT we estimate there would have been between 1,577 (53.6%) and 2,233 (75.9%) more TB cases in Baltimore, costing $18.8 million to $27.1 million. Cases prevented and expenditures saved increased with increased DOT participation. CONCLUSION: Our model predicts that Baltimore's TB decline accompanying DOT resulted in health care savings equal to twice the city's total TB control budget for this period. These results are most plausibly due to DOT, since it was the only major change in Baltimore's TB control program, and rising TB risk factors-AIDS, injection drug use, poverty-in a city where TB had been epidemic should have triggered a TB increase as in comparable US cities, rather than the observed decline. As national TB rates continue to decline it will be important to identify ways to capture and reinvest these savings to support effective TB control programs. AD - Annie E. Casey Foundation, Baltimore, Maryland 21202, USA. patc@aecf.org AN - 10751064 AU - Chaulk, C. P. AU - Friedman, M. AU - Dunning, R. DA - Mar DP - Nlm ET - 04/06 KW - Antitubercular Agents/ administration & dosage/economics Cost Savings Cost of Illness Humans Maryland/epidemiology Models, Economic Prevalence Risk Factors Tuberculosis, Pulmonary/ drug therapy/economics/ epidemiology LA - eng N1 - Chaulk, C P Friedman, M Dunning, R France The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease Int J Tuberc Lung Dis. 2000 Mar;4(3):201-7. PY - 2000 RN - fulltext fulltext_1208 SN - 1027-3719 (Print) 1027-3719 (Linking) SP - 201-7 ST - Modeling the epidemiology and economics of directly observed therapy in Baltimore T2 - Int J Tuberc Lung Dis TI - Modeling the epidemiology and economics of directly observed therapy in Baltimore VL - 4 ID - 2378 ER - TY - JOUR AB - Although tuberculosis (TB) screening of immigrants has been conducted for over 50 yr in many industrialized countries, its cost- effectiveness has never been evaluated. We prospectively compared the yield and cost-effectiveness of two immigrant TB screening programs, using close-contact investigation and passive case detection. Study subjects included all immigration applicants undergoing radiographic screening, already arrived immigrants requiring surveillance for inactive TB, and close contacts of active cases resident in Montreal, Quebec, Canada, who were referred from June 1996 to June 1997 to the Montreal Chest Institute (MCI), a referral center specializing in respiratory diseases. For all subjects seen, demographic data, investigations, diagnoses, and therapy were abstracted from administrative data bases and medical charts. Estimated costs of detecting and treating each prevalent active case and preventing future active cases, based on federal and provincial health reimbursement schedules, were compared with the costs for passively diagnosed cases of active TB. Over a period of 1 yr, the three programs detected 27 cases of prevalent active TB and prevented 14 future cases. As compared with passive case detection, close-contact investigation resulted in net savings of $815 for each prevalent active case detected and treated and of $2,186 for each future active case prevented. The incremental cost to treat each case of prevalent active TB was $39,409 for applicant screening and $24,225 for surveillance, and the cost of preventing each case was $33,275 for applicants and $65,126 for surveillance. Close-contact investigation was highly cost effective and resulted in net savings. Immigrant applicant screening and surveillance programs had a significant impact but were much less cost effective, in large part because of substantial operational problems. AD - Respiratory Epidemiology Unit, McGill University, Montreal, QC, Canada. AN - 11112118 AU - Dasgupta, K. AU - Schwartzman, K. AU - Marchand, R. AU - Tennenbaum, T. N. AU - Brassard, P. AU - Menzies, D. DA - Dec DP - Nlm ET - 12/09 KW - Cohort Studies Contact Tracing/ economics/methods/statistics & numerical data Cost-Benefit Analysis/economics/statistics & numerical data Emigration and Immigration/statistics & numerical data Humans Markov Chains Mass Screening/ economics/methods/statistics & numerical data Population Surveillance/methods Prospective Studies Quebec Sensitivity and Specificity Treatment Outcome Tuberculosis, Pulmonary/diagnosis/drug therapy/ economics/transmission LA - eng N1 - Dasgupta, K Schwartzman, K Marchand, R Tennenbaum, T N Brassard, P Menzies, D Comparative Study Research Support, Non-U.S. Gov't United states American journal of respiratory and critical care medicine Am J Respir Crit Care Med. 2000 Dec;162(6):2079-86. PY - 2000 RN - fulltext fulltext_1208 SN - 1073-449X (Print) 1073-449X (Linking) SP - 2079-86 ST - Comparison of cost-effectiveness of tuberculosis screening of close contacts and foreign-born populations T2 - Am J Respir Crit Care Med TI - Comparison of cost-effectiveness of tuberculosis screening of close contacts and foreign-born populations UR - http://ajrccm.atsjournals.org/content/162/6/2079.full.pdf VL - 162 ID - 2379 ER - TY - JOUR AB - Current theory in the molecular epidemiology of tuberculosis holds that tuberculosis cases harboring Mycobacterium tuberculosis strains with a common deoxyribonucleic acid (DNA) fingerprint are the result of recent M. tuberculosis transmission. Here we propose a mathematical approach independent of DNA fingerprinting to estimating the percentage of recent transmissions responsible for current tuberculosis incidence. The "short-term reproductive number" of tuberculosis is defined as the average number of tuberculosis cases developing within 1 year of infection. Multiplying the short-term reproductive number by the number of tuberculosis cases in each year and dividing by the subsequent year's tuberculosis case burden equals the proportion of tuberculosis cases in the subsequent year that are due to recent transmission. We carried out separate calculations for human immunodeficiency virus (HIV)-negative and HIV-positive tuberculosis cases. We applied the model to pulmonary (infectious) tuberculosis cases diagnosed in New York City during 1989-1993, using tuberculosis and AIDS surveillance data. Model-based estimates of the proportion of tuberculosis due to recent transmission were lower than estimates based on DNA fingerprints. Reconciliation of these divergent estimates may require the re-estimation of model parameters from data collected de novo, additional model development, and further advances in DNA fingerprinting methods. AD - Department of Preventive Medicine and Community Health, UMDNJ-New Jersey Medical School, Newark 07103-2714, USA. AN - 10874545 AU - Davidow, A. L. AU - Alcabes, P. AU - Marmor, M. DA - Jul DP - Nlm ET - 06/30 KW - Acquired Immunodeficiency Syndrome/complications Adult Aged DNA Fingerprinting DNA, Viral/analysis Disease Outbreaks Disease Progression Disease Transmission, Infectious Female Humans Male Middle Aged Models, Theoretical Mycobacterium tuberculosis New York City/epidemiology Tuberculosis, Pulmonary/ epidemiology/virology LA - eng N1 - Davidow, A L Alcabes, P Marmor, M 1P30AI27742/AI/NIAID NIH HHS/United States HL51517/HL/NHLBI NIH HHS/United States R21 AI42521/AI/NIAID NIH HHS/United States Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. United states Epidemiology (Cambridge, Mass.) Epidemiology. 2000 Jul;11(4):394-401. PY - 2000 RN - fulltext fulltext_1208 SN - 1044-3983 (Print) 1044-3983 (Linking) SP - 394-401 ST - The contribution of recently acquired Mycobacterium tuberculosis infection to the New York City tuberculosis epidemic, 1989-1993 T2 - Epidemiology TI - The contribution of recently acquired Mycobacterium tuberculosis infection to the New York City tuberculosis epidemic, 1989-1993 VL - 11 ID - 2380 ER - TY - JOUR AB - We have developed a computer-implemented, multivariate Markov chain model to project tuberculosis (TB) incidence in the United States from 1980 to 2010 in disaggregated demographic groups. Uncertainty in model parameters and in the projections is represented by fuzzy numbers. Projections are made under the assumption that current TB control measures will remain unchanged for the projection period. The projections of the model demonstrate an intermediate increase in national TB incidence (similar to that which actually occurred) followed by continuing decline. The rate of decline depends strongly on geographic, racial, and ethnic characteristics. The model predicts that the rate of decline in the number of cases among Hispanics will be slower than among white non-Hispanics and black non-Hispanics a prediction supported by the most recent data. AD - Department of Epidemiology and Biostatistics, School of Medicine, Case Western Reserve University, Cleveland, OH 44106-4945, USA. smd@hal.cwru.edu AN - 10756148 AU - Debanne, S. M. AU - Bielefeld, R. A. AU - Cauthen, G. M. AU - Daniel, T. M. AU - Rowland, D. Y. DA - Mar-Apr DP - Nlm ET - 04/11 KW - Adolescent Adult Aged Child Child, Preschool Computer Simulation Emigration and Immigration Ethnic Groups Female Humans Male Markov Chains Middle Aged Models, Biological Multivariate Analysis Tuberculosis, Pulmonary/ epidemiology United States/epidemiology LA - eng N1 - Debanne, S M Bielefeld, R A Cauthen, G M Daniel, T M Rowland, D Y Research Support, Non-U.S. Gov't United states Emerging infectious diseases Emerg Infect Dis. 2000 Mar-Apr;6(2):148-57. PY - 2000 RN - fulltext fulltext_1208 SN - 1080-6040 (Print) 1080-6040 (Linking) SP - 148-57 ST - Multivariate Markovian modeling of tuberculosis: forecast for the United States T2 - Emerg Infect Dis TI - Multivariate Markovian modeling of tuberculosis: forecast for the United States VL - 6 ID - 2381 ER - TY - JOUR AB - BACKGROUND: Tuberculosis (TB) is still amongst the most important causes of human morbidity and mortality, killing approximately two million people each year. Standard short-course chemotherapy (SSCC) can rapidly control illness and dramatically reduce the chance of death, but the impact of treatment has rarely been evaluated in these terms. METHOD: We developed a mathematical model that makes use of routinely-collected data to calculate the number of deaths directly prevented by TB treatment (i.e. excluding those due to reduced transmission). The method was applied to the world's largest TB control programme covering over 500 million people in 12 provinces of China. RESULTS: Counties which had been enrolled in the programme since 1991 were, by 1997, preventing at least 46% (37-56%) of the TB deaths that would otherwise have occurred. If replicated across the entire TB control programme area, this would amount to 30 000 (range 26 000-59 000) deaths directly prevented each year. CONCLUSIONS: Short-course chemotherapy has substantially reduced TB mortality in half of China. The analytical method described here could be applied to TB control operations in many other countries, and should help to quantify the true burden of tuberculosis alleviated by SSCC. AD - Communicable Disease Control, Prevention and Eradication, World Health Organization, Geneva, Switzerland. AN - 10869331 AU - Dye, C. AU - Fengzeng, Z. AU - Scheele, S. AU - Williams, B. DA - Jun DP - Nlm ET - 06/28 KW - Anti-Bacterial Agents/ therapeutic use China/epidemiology Cost of Illness Forecasting Humans Models, Theoretical Mortality/trends Preventive Medicine Tuberculosis, Pulmonary/drug therapy/ mortality/prevention & control LA - eng N1 - Dye, C Fengzeng, Z Scheele, S Williams, B England International journal of epidemiology Int J Epidemiol. 2000 Jun;29(3):558-64. PY - 2000 RN - fulltext fulltext_1208 SN - 0300-5771 (Print) 0300-5771 (Linking) SP - 558-64 ST - Evaluating the impact of tuberculosis control: number of deaths prevented by short-course chemotherapy in China T2 - Int J Epidemiol TI - Evaluating the impact of tuberculosis control: number of deaths prevented by short-course chemotherapy in China UR - http://ije.oxfordjournals.org/content/29/3/558.full.pdf VL - 29 ID - 2382 ER - TY - JOUR AB - Antibiotic resistance is a growing impediment to the control of infectious diseases worldwide, tuberculosis (TB) being among them. TB kills two million people each year and foci of multidrug-resistant TB (MDR-TB) have been identified in Eastern Europe, Africa, Asia, and Latin America. A critical question for health policy is whether standardized short-course chemotherapy for TB, based on cheap first-line drugs, can prevent and reverse the spread of drug resistance. Here we use mathematical modeling, in conjunction with treatment results from six countries, to show that best-practice short-course chemotherapy is highly likely to bring strains resistant to either of the two key drugs isoniazid and rifampicin under control and to prevent the emergence of MDR-TB. However, it is not certain to contain MDR-TB once it has emerged, partly because cure rates are too low. We estimate that approximately 70% of prevalent, infectious MDR-TB cases should be detected and treated each year, and at least 80% of these cases should be cured, in order to prevent outbreaks of MDR-TB. Poor control programs should aim to increase case detection and cure rates together for three reasons: (i) these variables act synergistically; (ii) when either is low, the other cannot succeed alone; and (iii) the second-line drugs needed to raise MDR-TB cure rates are few and extremely costly. We discuss the implications of these results for World Health Organization policy on the management of antibiotic resistance. AD - Communicable Disease Control, Prevention and Eradication, World Health Organization, CH-1211 Geneva 27, Switzerland. dyec@who.ch AN - 10859359 AU - Dye, C. AU - Williams, B. G. DA - Jul 5 DO - 10.1073/pnas.140102797 [doi] 140102797 [pii] DP - Nlm ET - 06/22 KW - Antitubercular Agents/ therapeutic use Drug Resistance, Multiple Humans Isoniazid/therapeutic use Models, Theoretical Practice Guidelines as Topic Rifampin/therapeutic use Tuberculosis, Pulmonary/ drug therapy/prevention & control World Health Organization L1 - internal-pdf://3473116560/Dye-2000-Criteria for the control of drug-resi.pdf LA - eng N1 - Dye, C Williams, B G United states Proceedings of the National Academy of Sciences of the United States of America Proc Natl Acad Sci U S A. 2000 Jul 5;97(14):8180-5. PY - 2000 RN - fulltext fulltext_1208 SN - 0027-8424 (Print) 0027-8424 (Linking) SP - 8180-5 ST - Criteria for the control of drug-resistant tuberculosis T2 - Proc Natl Acad Sci U S A TI - Criteria for the control of drug-resistant tuberculosis UR - http://www.pnas.org/content/97/14/8180.full.pdf https://www.ncbi.nlm.nih.gov/pmc/articles/PMC16690/pdf/pq008180.pdf VL - 97 ID - 2383 ER - TY - CHAP A2 - Portaels, F. A2 - Bastian, I. AB - Threshold theory in infectious disease epidemiology states that there is some combination of case detection and cure rates above which tuberculosis, including multidrug-resistant tuberculosis (MDR; resistance to at least isoniazid and rifampicin) cannot spread through a population. The analytical challenge in MDR control is to identify which combinations of case detection and cure rates ensure that the number of MDR cases will decline, and to calculate the rate of decline. AU - Dye, C. AU - Williams, B. G. AU - Bastian, I. C3 - www CY - Dortrecht LB - 25 N1 - RefMgr field[1]: Book Chapter RefMgr field[8]: Not in File PB - Kluwer Academic Publishers PY - 2000 RN - fulltext fulltext_1208 ST - Population dynamics and control of multidrug-resistant tuberculosis T2 - MDR Mycobacterium Tuberculosis TI - Population dynamics and control of multidrug-resistant tuberculosis ID - 2384 ER - TY - JOUR AB - Following primary tuberculosis (TB) infection, only approximately 10% of individuals develop active T.B. Most people are assumed to mount an effective immune response to the initial infection that limits proliferation of the bacilli and leads to long-lasting partial immunity both to further infection and to reactivation of latent bacilli remaining from the original infection. Infected individuals may develop active TB as a consequence of exogenous reinfection, i.e., acquiring a new infection from another infectious individual. Our results in this paper suggest that exogenous reinfection has a drastic effect on the qualitative dynamics of TB. The incorporation of exogenous reinfection into our TB model allows the possibility of a subcritical bifurcation at the critical value of the basic reproductive number R(0)=1, and hence the existence of multiple endemic equilibria for R(0)<1 and the exogenous reinfection rate larger than a threshold. Our results suggest that reducing R(0) to be smaller than one may not be sufficient to eradicate the disease. An additional reduction in reinfection rate may be required. These results may also partially explain the recently observed resurgence of TB. AD - Department of Mathematics, Purdue University, West Lafayette, Indiana, 47907-1395, USA. AN - 10828216 AU - Feng, Z. AU - Castillo-Chavez, C. AU - Capurro, A. F. DA - May DO - 10.1006/tpbi.2000.1451 [doi] S0040-5809(00)91451-5 [pii] DP - Nlm ET - 06/01 KW - Disease Susceptibility Emigration and Immigration Endemic Diseases/statistics & numerical data Humans Models, Biological Tuberculosis/ epidemiology/prevention & control/ transmission LA - eng N1 - Feng, Z Castillo-Chavez, C Capurro, A F Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. United states Theoretical population biology Theor Popul Biol. 2000 May;57(3):235-47. PY - 2000 RN - fulltext fulltext_1208 SN - 0040-5809 (Print) 0040-5809 (Linking) SP - 235-47 ST - A model for tuberculosis with exogenous reinfection T2 - Theor Popul Biol TI - A model for tuberculosis with exogenous reinfection UR - http://ac.els-cdn.com/S0040580900914515/1-s2.0-S0040580900914515-main.pdf?_tid=3bb76eba266c190e215b1de750b07574&acdnat=1345012329_4b250005c2ef4164ec2df2d398ddaf54 VL - 57 ID - 2385 ER - TY - JOUR AB - OBJECTIVE: Because delay in the diagnosis of tuberculosis (TB) contributes to the spread of disease and the associated mortality risk, the authors examined the effectiveness and cost of recent advances in methods of diagnosing TB and testing for drug susceptibility, comparing these rapid methods to traditional approaches. METHODS: Decision analysis was used to compare newer rapid and older nonrapid methods for diagnosing TB and testing for drug susceptibility. The average time to diagnosis, average time to treatment, average mortality, and cost of caring for patients evaluated for TB were compared. RESULTS: Using a combination of solid medium and broth cultures, nucleic acid probes for identification, and radiometric broth drug susceptibility testing would lead to diagnosis on average 15 days faster and to appropriate therapy on average five days sooner than methods currently employed by many U.S. laboratories. The average mortality would drop by five patients per 1000 patients evaluated (31%) and the average cost per patient would drop by $272 (18%). CONCLUSIONS: In this era of cost containment, it is important to incorporate test sensitivity and specificity when evaluating technologies. Tests with higher unit costs may lead to lower medical expenditures when diagnostic accuracy and speed are improved. U.S. laboratories should employ available rapid techniques for the diagnosis of TB. AD - Department of Health and Social Behavior, Harvard School of Public Health, Boston, MA 02115, USA. AN - 10822480 AU - Heymann, S. J. AU - Brewer, T. F. AU - Ettling, M. DA - Nov-Dec ET - 05/24 KW - Bacteriological Techniques/economics/*standards Cost Control Cost-Benefit Analysis Decision Trees Drug Resistance, Microbial Health Expenditures/statistics & numerical data Humans Mass Screening/economics/*methods Microbial Sensitivity Tests Mycobacterium tuberculosis/*isolation & purification Prevalence Reproducibility of Results Sensitivity and Specificity Time Factors Tuberculosis/*diagnosis/economics/*microbiology/mortality/prevention & control United States/epidemiology L1 - internal-pdf://0325095967/Heymann-2000-Effectiveness and cost of rapid a.pdf LA - eng N1 - Heymann, S J Brewer, T F Ettling, M 1 F32 HS00079/HS/AHRQ HHS/United States Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. United states Public health reports (Washington, D.C. : 1974) Public Health Rep. 1997 Nov-Dec;112(6):513-23. PY - 2000 RN - fulltext fulltext_1208 SN - 0033-3549 (Print) 0033-3549 (Linking) SP - 513-23 ST - Effectiveness and cost of rapid and conventional laboratory methods for Mycobacterium tuberculosis screening T2 - Public Health Rep TI - Effectiveness and cost of rapid and conventional laboratory methods for Mycobacterium tuberculosis screening UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=10822480 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1381931/pdf/pubhealthrep00037-0071.pdf VL - 112 ID - 2343 ER - TY - JOUR AB - OBJECTIVE: Tuberculosis (TB) control programs have been less successful among children than among adults in the United States. Between 1992 and 1997, the rate of decline of TB cases among 0- to 14-year-old children was less than the rate of decline among any other age group of US-born persons. Because of the higher prevalence of active TB among adults and their higher infectivity, most programs for TB in the United States have targeted adults. The inherent assumption has been that by targeting adults, from whom children may become infected, TB morbidity and mortality among children also will be reduced effectively. METHODS: Using a semi-Markov model that divided the US population into age groups <15 years old and >/=15 years old and into 18 clinical states based on the risk for or presence of TB and human immunodeficiency virus infection, we developed a computer-based simulation model to examine the effect of a range of potential TB control strategies on projected TB cases and deaths in children. We compare the impact of interventions targeted at children with the impact of interventions targeted at adults on pediatric morbidity and mortality. RESULTS: After 10 years, a 5% increase in the number of adults with TB who enter treatment would only lead to a.05% decline in TB cases among children, compared with predicted cases without this intervention. Improving treatment efficacy among those adults who are already receiving treatment for their TB leads to a smaller decline in cases among children of only.003%. In contrast, a 5% increase in the number of children who enter treatment leads to a 25% decline, after 10 years, in the number of TB cases among children and a 16% decline in the number of TB deaths. In the presence of immigration of tuberculin-positive children, the benefit of targeting programs directly at children is magnified. CONCLUSIONS: Marginal changes in programs targeted directly at children are significantly more effective at further reducing pediatric TB morbidity and mortality than the same changes in programs targeted at adults with the indirect goal of reducing spread to children. Marginal increases in the number of children who enter treatment are far more effective at decreasing morbidity and mortality than equivalent marginal increases in treatment effectiveness. Unfortunately, declining insurance coverage and increasing restrictions on services to immigrants have made it harder for those who are at greatest risk of TB to get medical care. Marginal increases in preventive therapy rates substantially reduce future pediatric TB cases and deaths among children with TB infection and human immunodeficiency virus. AD - Harvard School of Public Health, Brigham and Women's Hospital, Boston, MA 02115, USA. jheymann@hsph.harvard.edu AN - 10878170 AU - Heymann, S. J. AU - Brewer, T. F. AU - Wilson, M. E. AU - Colditz, G. A. AU - Fineberg, H. V. DA - Jul DP - Nlm ET - 07/06 KW - Adolescent Adult Child Child, Preschool Computer Simulation Humans Infant Infant, Newborn Prevalence Survival Rate Tuberculosis/epidemiology/mortality/ prevention & control United States/epidemiology LA - eng N1 - Heymann, S J Brewer, T F Wilson, M E Colditz, G A Fineberg, H V 1K08 AI01444-01A1/AI/NIAID NIH HHS/United States Research Support, U.S. Gov't, Non-P.H.S. Research Support, U.S. Gov't, P.H.S. United states Pediatrics Pediatrics. 2000 Jul;106(1):E1. PY - 2000 RN - fulltext fulltext_1208 SN - 1098-4275 (Electronic) 0031-4005 (Linking) SP - E1 ST - Pediatric tuberculosis: what needs to be done to decrease morbidity and mortality T2 - Pediatrics TI - Pediatric tuberculosis: what needs to be done to decrease morbidity and mortality UR - http://pediatrics.aappublications.org/content/106/1/e1.full.pdf VL - 106 ID - 2386 ER - TY - JOUR AB - Isoniazid taken daily for 12 mo and isoniazid and rifampin taken daily for 4 mo are both recommended options for patients with radiographic evidence of previous tuberculosis and positive tuberculin skin tests who have not had prior treatment. We compared the completion rates, number of adverse effects, and cost effectiveness of these two regimens. Patients were treated at the San Francisco Tuberculosis Clinic from 1993 through 1996. A Markov model was developed to assess impact on life expectancy and costs. One thousand twenty-two patients, with a mean age of 52 yr, and > 90% foreign born, were treated; 545 received isoniazid and 477 received isoniazid and rifampin. For isoniazid, 79.8% completed 12 mo of therapy and 4.9% had adverse effects versus 83.6% completion, 6.1% adverse effects for isoniazid and rifampin (p > 0.05 for all between-group comparisons). Both regimens increased life expectancy by 1.4-1.5 yr. Compared with isoniazid, isoniazid and rifampin produced net incremental savings of $135 per patient treated. In patients with radiographic evidence of prior tuberculosis who have not been previously treated, isoniazid for 12 mo and isoniazid and rifampin for 4 mo have similar rates of completion and adverse effects, and both increase life expectancy compared with no treatment. Isoniazid and rifampin for 4 mo is cost saving compared with isoniazid alone. This advantage was maintained even when compared with 9 mo of isoniazid, the new American Thoracic Society/Centers for Disease Control (ATS/CDC) recommendation for treatment with isoniazid alone. AD - Division of Pulmonary and Critical Care Medicine, San Francisco General Hospital Medical Center, and the Department of Medicine, University of California, San Francisco, CA, USA. rjasmer@itsa.ucsf.edu AN - 11069790 AU - Jasmer, R. M. AU - Snyder, D. C. AU - Chin, D. P. AU - Hopewell, P. C. AU - Cuthbert, S. S. AU - Antonio Paz, E. AU - Daley, C. L. DA - Nov DP - Nlm ET - 11/09 J2 - American journal of respiratory and critical care medicine KW - Antitubercular Agents/ administration & dosage/economics Cost-Benefit Analysis Drug Administration Schedule Drug Costs Drug Therapy, Combination Female Health Care Costs Humans Isoniazid/ administration & dosage/adverse effects/economics Life Expectancy Male Middle Aged Outcome Assessment (Health Care) Patient Compliance Recurrence Rifampin/ administration & dosage/adverse effects/economics San Francisco Tuberculosis, Pulmonary/ drug therapy/ economics/radiography LA - eng N1 - Jasmer, R M Snyder, D C Chin, D P Hopewell, P C Cuthbert, S S Antonio Paz, E Daley, C L AI01549/AI/NIAID NIH HHS/United States AI34238/AI/NIAID NIH HHS/United States Comparative Study Research Support, U.S. Gov't, P.H.S. United states Am J Respir Crit Care Med. 2000 Nov;162(5):1648-52. PY - 2000 RN - fulltext fulltext_1208 SN - 1073-449X (Print) 1073-449X (Linking) SP - 1648-52 ST - Twelve months of isoniazid compared with four months of isoniazid and rifampin for persons with radiographic evidence of previous tuberculosis: an outcome and cost-effectiveness analysis T2 - Am J Respir Crit Care Med TI - Twelve months of isoniazid compared with four months of isoniazid and rifampin for persons with radiographic evidence of previous tuberculosis: an outcome and cost-effectiveness analysis UR - http://ajrccm.atsjournals.org/content/162/5/1648.full.pdf VL - 162 ID - 2387 ER - TY - JOUR AB - We use 2 simple mathematical models (one a preexposure vaccine model and the other a postexposure vaccine model) to provide general insight into the effects of vaccination on tuberculosis epidemics. We discuss how these models can be used as health policy tools: to identify which vaccines are "equivalent," to design control strategies, and to predict the epidemiological impact of different vaccination strategies. Our results show that even moderately effective vaccines could have a significant effect on reducing tuberculosis epidemics if they can be coupled with moderate to high treatment rates. We suggest that both preexposure and postexposure tuberculosis vaccines can be used to help eliminate tuberculosis in developing countries. In developed countries, only a preexposure vaccine (used in combination with a high level of treatment) would be necessary to eliminate tuberculosis. AD - Francis I. Proctor Foundation and Department of Ophthalmology, University of California San Francisco, San Francisco, CA 94143, USA. AN - 10875909 AU - Lietman, T. AU - Blower, S. M. DA - Jun DO - CID990621 [pii] 10.1086/313881 [doi] DP - Nlm ET - 07/06 KW - BCG Vaccine Disease Outbreaks/ prevention & control Humans Models, Biological Tuberculosis, Pulmonary/epidemiology/ prevention & control Vaccination LA - eng N1 - Lietman, T Blower, S M K08AI01441/AI/NIAID NIH HHS/United States R01AI41935/AI/NIAID NIH HHS/United States Research Support, U.S. Gov't, P.H.S. Review United states Clinical infectious diseases : an official publication of the Infectious Diseases Society of America Clin Infect Dis. 2000 Jun;30 Suppl 3:S316-22. PY - 2000 RN - fulltext fulltext_1208 SN - 1058-4838 (Print) 1058-4838 (Linking) SP - S316-22 ST - Potential impact of tuberculosis vaccines as epidemic control agents T2 - Clin Infect Dis TI - Potential impact of tuberculosis vaccines as epidemic control agents UR - http://cid.oxfordjournals.org/content/30/Supplement_3/S316.full.pdf VL - 30 Suppl 3 ID - 2388 ER - TY - JOUR AB - OBJECTIVE: To assess the cost-effectiveness of adding school based Mantoux screening programs to the New South Wales current TB prevention strategy. METHOD: A decision analysis model compared the costs and consequences of screening strategies against the current no-screen strategy. Costs associated with screening and with treating future cases of TB were considered. Consequences considered were deaths and adult cases of TB prevented. The study was based on data from prevalence surveys conducted in 1992 and 1994 in Central and South Western Sydney, New South Wales. Screening strategies considered were screening all or only overseas born (OSB) 6 year olds and all or only OSB 14 year olds in school settings. RESULTS: Screening 14 year olds prevented more deaths and adult cases of TB than screening 6 year olds for a similar cost. For both age groups targeted screening of OSB children was more cost-effective than screening all children. Targeted screening of 14 year olds--the most cost effective option--cost $17,956 (costs and benefits discounted at 5%) per adult case prevented, equivalent to approximately $130,000 per life year saved. The cost-effectiveness ratios decline substantially if lower discount rates and less conservative assumptions are applied. CONCLUSION: Targeted screening was more cost effective than screening all children, however, there are ethical implications of targeting a group based on their origin of birth. IMPLICATIONS: As prevention and control of TB continues to be a high priority for NSW, the implications of a school based screening program should be seriously considered. AD - Centre for Health Economics, Research and Evaluation, University of Sydney, New South Wales. AN - 10937400 AU - Lowin, A. AU - Slater, J. AU - Hall, J. AU - Alperstein, G. DA - Jun DP - Nlm ET - 08/11 J2 - Australian and New Zealand journal of public health KW - Adolescent Adult Child Cost-Benefit Analysis Decision Theory Health Services Research Humans Mass Screening/ economics/methods New South Wales/epidemiology School Health Services/ economics Tuberculin Test/economics/ methods Tuberculosis/ diagnosis/prevention & control LA - eng N1 - Lowin, A Slater, J Hall, J Alperstein, G Research Support, Non-U.S. Gov't Australia Aust N Z J Public Health. 2000 Jun;24(3):247-53. PY - 2000 RN - fulltext fulltext_1208 SN - 1326-0200 (Print) 1326-0200 (Linking) SP - 247-53 ST - Cost effectiveness analysis of school based Mantoux screening for TB infection T2 - Aust N Z J Public Health TI - Cost effectiveness analysis of school based Mantoux screening for TB infection UR - http://onlinelibrary.wiley.com/store/10.1111/j.1467-842X.2000.tb01564.x/asset/j.1467-842X.2000.tb01564.x.pdf?v=1&t=h6geefvr&s=99a4a3e086ebe7c619f8cc41eb3b0e94c9846b8f VL - 24 ID - 2390 ER - TY - JOUR AB - INTRODUCTION: The potential cost-effectiveness of screening depends on the risk of tuberculosis (TB) in the population being screened and the rate at which the screening outcome (prevention) is achieved. AIMS: To compare the cost-effectiveness of contact screening for TB for: (1) contact screening as it actually occurred in Victoria in 1991 (Model 1); (2) the process which should have occurred had the 1991 contact screening guidelines been followed (Model 2); (3) a hypothetical evidence-based model (Model 3). METHODS: Three models were constructed according to the aims. The cost-effectiveness of contact screening is presented as costs to government per unit outcome (in the form of cases prevented, cases found and contacts traced) for each model. Assumptions about disease behaviour were consistent between models. A sensitivity analysis was performed to examine the effect of the assumptions made in Model 3 about rates of referral and treatment of infected contacts, and about the efficacy of isoniazid (INH) in preventing TB. RESULTS: The total cost of Model 1 was greater than that of the other Models. Model 1 is the least cost-effective, costing $309 065 per case prevented, and Model 3 is the most cost-effective, costing $32 210 per case prevented. The cost of Model 2 was $58 742 per case prevented. The incremental cost-effectiveness of Model 3 compared to Model 2 is $107 per additional contact screened, and $3881 per additional case prevented. Case finding is not as cost-effective as best-practice case prevention, ranging from $231 799 per case found in Model 1 to $205 596 per case found in Model 2. The sensitivity analysis shows that the cost-effectiveness of Model 3 decreases with lower referral rates, lower rates of preventive therapy, and lower efficacy of INH. However, even allowing for reduced programme parameters, Model 3 is most cost-effective. DISCUSSION: Costing policy options is an important component of programme delivery, but needs to be considered in the context of the product being purchased, e.g. the prevention of disease, or case finding. Case finding as a product of contact screening is expensive in all three models. Prevention of TB, on the other hand, can be cost-effective, as shown in Model 3. It was least cost-effective in Model 1, largely because prevention was not considered a priority, and few infected contacts actually received preventive therapy. Clear programme aims, adherence to guidelines and high rates of preventive therapy are essential in order to achieve cost-effectiveness. AD - Department of Public Health and Community Medicine, Westmead Hospital, Westmead, Australia. RainaM@nch.edu.au AN - 10903541 AU - Macintyre, C. R. AU - Plant, A. J. AU - Hendrie, D. DA - Jul DO - 10.1002/1099-1050(200007)9:5<411::AID-HEC524>3.0.CO;2-9 [pii] ET - 07/21 KW - Antitubercular Agents/economics/therapeutic use Contact Tracing Cost of Illness Cost-Benefit Analysis Drug Costs *Evidence-Based Medicine Humans Isoniazid/economics/therapeutic use Mass Screening/*economics/standards Models, Econometric New South Wales *Practice Guidelines as Topic Tuberculosis/*diagnosis/drug therapy/economics/*prevention & control LA - eng N1 - Macintyre, C R Plant, A J Hendrie, D Research Support, Non-U.S. Gov't England Health economics Health Econ. 2000 Jul;9(5):411-21. PY - 2000 RN - fulltext fulltext_1208 SN - 1057-9230 (Print) 1057-9230 (Linking) SP - 411-21 ST - The cost-effectiveness of evidence-based guidelines and practice for screening and prevention of tuberculosis T2 - Health Econ TI - The cost-effectiveness of evidence-based guidelines and practice for screening and prevention of tuberculosis UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=10903541 VL - 9 ID - 2391 ER - TY - JOUR AB - We consider a simple unstructured individual based stochastic epidemic model with contact tracing. Even in the onset of the epidemic, contact tracing implies that infected individuals do not act independent of each other. Nevertheless, it is possible to analyze the embedded non-stationary Galton-Watson process. Based upon this analysis, threshold theorems and also the probability for major outbreaks can be derived. Furthermore, it is possible to obtain a deterministic model that approximates the stochastic process, and in this way, to determine the prevalence of disease in the quasi-stationary state and to investigate the dynamics of the epidemic. AD - Biomathematik, Universitat Tubingen, Auf der Morgenstelle 10, D-72076, Tubingen, Germany. johannes.mueller@uni-tuebingen.de AN - 10704637 AU - Muller, J. AU - Kretzschmar, M. AU - Dietz, K. DA - Mar DO - S0025-5564(99)00061-9 [pii] DP - Nlm ET - 03/08 KW - Communicable Diseases/epidemiology/ transmission Computer Simulation Contact Tracing/economics/ statistics & numerical data Disease Outbreaks/ statistics & numerical data Female Humans Male Models, Biological Prevalence Sexually Transmitted Diseases/epidemiology Stochastic Processes Tuberculosis/epidemiology LA - eng N1 - Muller, J Kretzschmar, M Dietz, K Comparative Study United states Mathematical biosciences Math Biosci. 2000 Mar;164(1):39-64. PY - 2000 RN - fulltext fulltext_1208 SN - 0025-5564 (Print) 0025-5564 (Linking) SP - 39-64 ST - Contact tracing in stochastic and deterministic epidemic models T2 - Math Biosci TI - Contact tracing in stochastic and deterministic epidemic models UR - http://ac.els-cdn.com/S0025556499000619/1-s2.0-S0025556499000619-main.pdf?_tid=70d9bb8a42a340b1a448eb257fe83e11&acdnat=1345012817_4f26fbbdf286867526670b1b80de9081 VL - 164 ID - 2392 ER - TY - JOUR AB - Most models for contaminant dispersion in indoor air are deterministic and do not account for the probabilistic nature of the pollutant concentration at a given room position and time. Such variability can be important when estimating concentrations involving small numbers of contaminant particles. This article describes the use of probabilistic models termed Markov chains to account for a portion of this variability. The deterministic and Markov models are related in that the former provide the expected concentration values. To explain this relationship, a single-zone (well-mixed room) scenario is described as a Markov chain. Subsequently, a two-zone room is cast as a Markov model, and the latter is applied to assessing a health care worker's risk of tuberculosis infection. Airborne particles carrying Mycobacterium tuberculosis bacilli are usually present in small numbers in a room occupied by an infectious tuberculosis patient. For a given scenario, the Markov model permits estimates of variability in exposure intensity and the resulting variability in infection risk. AD - Center for Occupational and Environmental Health, School of Public Health, University of California, Berkeley 94720, USA. AN - 10976677 AU - Nicas, M. DA - Jul-Aug DP - Nlm ET - 09/08 KW - Air Microbiology Air Pollution, Indoor/ analysis Humans Markov Chains Models, Statistical Occupational Exposure/analysis/prevention & control Tuberculosis/prevention & control/transmission Ventilation LA - eng N1 - Nicas, M K01-OH00155-01/OH/NIOSH CDC HHS/United States Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. United states AIHAJ : a journal for the science of occupational and environmental health and safety AIHAJ. 2000 Jul-Aug;61(4):484-91. PY - 2000 RN - fulltext fulltext_1208 SN - 1529-8663 (Print) 1529-8663 (Linking) SP - 484-91 ST - Markov modeling of contaminant concentrations in indoor air T2 - AIHAJ TI - Markov modeling of contaminant concentrations in indoor air VL - 61 ID - 2393 ER - TY - JOUR AB - The present study examines whether pulmonary tuberculosis (PTB) has an annual seasonal pattern. A mathematical model is also obtained to forecast the pattern of incidence. The data for the study are the cases of PTB reported throughout Spain, published in the Epidemiology Bulletin by the Carlos III Health Center of the Spanish Ministry of Health in a 26-year period, 1971-1996. The analytical results show that the low rates in tuberculosis notifications over the period 1971-1981 have changed, halting in 1982 and reversing with high incidence from 1983 onwards. An annual seasonal pattern was also shown with higher incidence during summer and autumn. With the mathematical model we predicted the disease behaviour in 1997 and the results were compared to the reported cases. In Spain, as in several industrialised countries, the reason for this recent increase in the number of reported cases is, mainly, the human immunodeficiency virus (HIV) infection. The seasonal trend, with higher incidence in winter, can be attributed to the increase in indoor activities, much more common than in a warm climate. The tubercle bacilli expelled from infected persons in a room with closed windows may remain infectious for a long time, increasing the risk of exposure of healthy persons to the bacilli. As the preclinical period, from exposure to clinical onset, may be of several weeks, the high incidence in spring would be explained. Moreover, in winter and spring the infections of viral aetiology, like flu, are more frequent and cause immunological deficiency which is another reason for the seasonal trend observed. An incidence greater than that foreseen by the mathematical model would express a failure in epidemiologic surveillance, and thus the results of this study may be used to assess a quality of the preventive measures. AD - Statistical Department, University of Barcelona, Spain. rios@porthos.bio.ub.es AN - 10997837 AU - Rios, M. AU - Garcia, J. M. AU - Sanchez, J. A. AU - Perez, D. DA - May DP - Nlm ET - 09/21 KW - Cohort Studies Humans Likelihood Functions Models, Statistical Seasons Spain/epidemiology Time Factors Tuberculosis, Pulmonary/ epidemiology LA - eng N1 - Rios, M Garcia, J M Sanchez, J A Perez, D Comparative Study Netherlands European journal of epidemiology Eur J Epidemiol. 2000 May;16(5):483-8. PY - 2000 RN - fulltext fulltext_1208 SN - 0393-2990 (Print) 0393-2990 (Linking) SP - 483-8 ST - A statistical analysis of the seasonality in pulmonary tuberculosis T2 - Eur J Epidemiol TI - A statistical analysis of the seasonality in pulmonary tuberculosis VL - 16 ID - 2394 ER - TY - JOUR AB - All adult immigrant applicants to Canada undergo chest radiographic screening for tuberculosis (TB). Tuberculin skin testing could reduce the number of chest X-rays, and identify more candidates for prophylaxis. We modeled the cost-effectiveness of chest radiography and tuberculin skin testing for TB prevention over a 20-yr time frame, among three simulated cohorts of 20-yr-old immigrants. Compared with no screening, radiographic screening prevented 4.3% of expected active TB cases in the highest risk cohort (50% TB-infected, 10% human immunodeficiency virus [HIV] seroprevalence), and 8.0% in the lowest risk cohort (5% TB-infected, 1% HIV seroprevalence). Tuberculin skin testing further reduced the expected incidence 8.0% and 4.0%, respectively. Compared with no screening, radiographic screening cost $3,943 Canadian per active TB case prevented in the highest risk cohort, and $236,496 per case prevented in the lowest risk group. Compared with radiographic screening, mass tuberculin skin testing cost $32,601 per additional case prevented in the highest risk group, and $68,799 per additional case prevented in the lowest risk group. Chest radiographic screening of young immigrants from countries with a high prevalence of TB is a relatively inexpensive means of TB prevention. Tuberculin skin testing is considerably less cost-effective. For immigrants from low-prevalence countries, both interventions are extremely costly with negligible impact. The cost-effectiveness of either strategy would be greatly enhanced by increased adherence to chemoprophylaxis recommendations. Radiographic screening of groups with a high prevalence of tuberculous infection will then likely save money. AD - Respiratory Division, McGill University Health Centre, and Respiratory Epidemiology Unit, McGill University, Montreal, Quebec, Canada. kevins@meakins.lan.mcgill.ca AN - 10712322 AU - Schwartzman, K. AU - Menzies, D. DA - Mar DP - Nlm ET - 03/11 KW - AIDS-Related Opportunistic Infections/economics/epidemiology/prevention & control Adult Canada Cost-Benefit Analysis Cross-Sectional Studies Emigration and Immigration/ statistics & numerical data Female Humans Male Mass Chest X-Ray/economics Mass Screening/economics Tuberculin Test/economics Tuberculosis, Pulmonary/economics/ epidemiology/prevention & control LA - eng N1 - Schwartzman, K Menzies, D Comparative Study Research Support, Non-U.S. Gov't United states American journal of respiratory and critical care medicine Am J Respir Crit Care Med. 2000 Mar;161(3 Pt 1):780-9. PY - 2000 RN - fulltext fulltext_1208 SN - 1073-449X (Print) 1073-449X (Linking) SP - 780-9 ST - Tuberculosis screening of immigrants to low-prevalence countries. A cost-effectiveness analysis T2 - Am J Respir Crit Care Med TI - Tuberculosis screening of immigrants to low-prevalence countries. A cost-effectiveness analysis VL - 161 ID - 2395 ER - TY - JOUR AB - We propose a stepwise mutation model to describe the dynamics of DNA fingerprint variation in Mycobacterium tuberculosis. The genome of M. tuberculosis carries insertion sequences (IS6110) that are relatively stable over time periods of months but have an observable transposition rate over longer time scales. Variability in copy number and genomic location of (IS6110) can be harnessed to generate a DNA fingerprint for each strain, by digesting the genome with a restriction enzyme and using a portion of the element as a probe for Southern blots. The number of bands found for a given genome approximates the number of copies of IS6110 it carries. A large data set of such fingerprints from tuberculosis (TB) cases in San Francisco provides an observed distribution of IS6110 copy number. Implementation of the model through deterministic and stochastic simulation indicates some general features of IS/TB dynamics. By comparing observations with outcomes of the model, we conclude that the IS/TB system is very heterogeneous and far from equilibrium. We find that the transposition parameters have a much stronger effect than the epidemic parameters on copy number distribution. AD - Department of Biological Sciences, and Division of Infectious Diseases and Geographic Medicine, Stanford University, CA 94305, USA. markt@charles.stanford.edu AN - 10716736 AU - Tanaka, M. M. AU - Small, P. M. AU - Salamon, H. AU - Feldman, M. W. DA - Mar 28 KW - DNA Fingerprinting *Epidemiology, Molecular Human Models, Genetic Monte Carlo Method Mycobacterium tuberculosis/*genetics *Repetitive Sequences, Nucleic Acid Support, Non-U.S. Gov't Support, U.S. Gov't, P.H.S. Tuberculosis/*epidemiology N1 - 20202670 0027-8424 Journal Article PY - 2000 RN - fulltext fulltext_1208 SP - 3532-3537 ST - The dynamics of repeated elements: applications to the epidemiology of tuberculosis T2 - Proceedings of the National Academy of Sciences of the USA TI - The dynamics of repeated elements: applications to the epidemiology of tuberculosis UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=10716736http://www.ncbi.nlm.nih.gov/pmc/articles/PMC16274/pdf/pq003532.pdf VL - 97 ID - 2396 ER - TY - JOUR AU - Taylor, Z. DA - 2000 KW - Americas control strategies cost effectiveness elimination infection interventions preventive therapy screening tuberculosis USA LB - 8025 N1 - TY - JOUR TB Periodical PY - 2000 RN - fulltext fulltext_1208 SP - S127-S133 ST - The cost-effectiveness of screening for latent tuberculosis infection T2 - Int.J.Tuberc.Lung Dis. TI - The cost-effectiveness of screening for latent tuberculosis infection VL - 4(suppl 2) ID - 2397 ER - TY - JOUR AB - The lifetime risk of developing disease, the incubation period, and the time period between infection and transmission (the serial interval) are three important measures for interpreting trends in tuberculous infection and disease but are complicated by strong age dependencies regarding disease risk and by the potential for reinfection to occur. By using a model of the epidemiology of tuberculosis in England and Wales, the authors demonstrated that all three measures changed dramatically during the 20th century largely as a result of declines in the risk of infection. The estimated lifetime risk was highest following infection in early adulthood and declined with year of infection; the age-weighted average was approximately 12% during the last 50 years. Incubation period distributions depend on whether they are viewed prospectively (from infection to disease onset) or retrospectively (since infection for cases with disease onset at a particular time). As children rarely develop infectious forms of tuberculosis, infections acquired in childhood are associated with considerably longer serial intervals than those acquired in adulthood. These unusual properties are probably shared by other infections with long intervals between infection and disease. The results are important for interpreting data on transmission patterns, as are now being derived from molecular epidemiologic studies. AD - Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, United Kingdom. emilia.vynnycky@lshtm.ac.uk AN - 10933272 AU - Vynnycky, E. AU - Fine, P. E. DA - Aug 1 ET - 08/10 J2 - American journal of epidemiology KW - Adult Aged Child Child, Preschool England/epidemiology Humans Incidence Male *Models, Statistical Molecular Epidemiology Recurrence Risk Time Factors Tuberculosis, Pulmonary/*epidemiology/mortality/transmission Wales/epidemiology LA - eng M3 - Research Support, Non-U.S. Gov't N1 - Vynnycky, E Fine, P E Am J Epidemiol. 2000 Aug 1;152(3):247-63. PY - 2000 RN - fulltext fulltext_1208 SN - 0002-9262 (Print) 0002-9262 (Linking) SP - 247-63 ST - Lifetime risks, incubation period, and serial interval of tuberculosis T2 - Am J Epidemiol TI - Lifetime risks, incubation period, and serial interval of tuberculosis UR - http://www.ncbi.nlm.nih.gov/pubmed/10933272http://aje.oxfordjournals.org/content/152/3/247.full.pdf VL - 152 ID - 2398 ER - TY - JOUR AB - OBJECTIVE: To describe the economic benefits of a better tuberculosis (TB) vaccine by modeling prevented TB medical spending and lost productivity throughout the world. DESIGN: One model is based on benefits obtained from reducing the impact of TB on health spending. An alternative model is based on minimizing the impact of TB on health spending and lost productivity due to death and disability. Both models are applied to various world populations based on secondary data. RESULTS: In terms of avoided medical spending, preventing 100% of the TB risk in a single individual is estimated to be worth from $38 for males in formerly socialist countries to S0.23 for children in Asia. More than 1 billion people would reckon their expected medical savings to exceed $25.00 if they received a 75% effective vaccine of 10 years' duration. Preventing lost productivity is worth substantially more throughout the world. CONCLUSIONS: Improved TB vaccines would be of substantial immediate financial value to most of the populations of the world, including the poorest. The scientific uncertainties surrounding the development of a better vaccine could be a larger obstacle than investor uncertainty over whether a vaccine would be profitable. AD - Department of Population and Family Health Sciences, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland 21205, USA. dbishai@jhsph.edu AN - 11716349 AU - Bishai, D. M. AU - Mercer, D. DA - Nov DP - Nlm ET - 11/22 KW - Adolescent Adult Aged Bacterial Vaccines/ economics Child Cost Savings Cost of Illness Efficiency Female Health Care Costs Humans Male Middle Aged Models, Economic Mycobacterium tuberculosis/ immunology Risk Factors Tuberculosis/ economics/epidemiology/ prevention & control Vaccination/ economics LA - eng N1 - Bishai, D M Mercer, D Research Support, Non-U.S. Gov't France The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease Int J Tuberc Lung Dis. 2001 Nov;5(11):984-93. PY - 2001 RN - fulltext fulltext_1208 SN - 1027-3719 (Print) 1027-3719 (Linking) SP - 984-93 ST - Modeling the economic benefits of better TB vaccines T2 - Int J Tuberc Lung Dis TI - Modeling the economic benefits of better TB vaccines VL - 5 ID - 2399 ER - TY - JOUR AB - This study estimated to what extent tuberculosis transmission in the Netherlands depends on the age and sex of source cases. DNA fingerprints of Mycobacterium tuberculosis isolates were matched to patient information in the Netherlands Tuberculosis Register for 1993-1998. Clusters were defined as groups of patients with pulmonary tuberculosis whose isolates had identical DNA fingerprints. Source cases were assigned by using two models. The first-case model assumed that the first diagnosed case was the source case. The incidence rate model estimated source case probabilities from the incidence rates of potential source cases and the time of diagnosis. DNA fingerprints of 6,102 isolates were matched to patient information on 5,080 (83%) cases, 3,479 of whom had pulmonary disease. According to both models, the number of infectious cases generated per source case was lower for female than for male source cases and decreased with increasing age of the source case. The authors concluded that transmission of tuberculosis is associated with the age and sex of source cases as well as the age of secondary cases. Increased transmission among immigrant groups in the Netherlands is largely attributable to the relatively young age of immigrant source cases. AD - Royal Netherlands Tuberculosis Association, The Hague, The Netherlands. borgdorffm@kncvtbc.nl AN - 11700248 AU - Borgdorff, M. W. AU - Nagelkerke, N. J. AU - de Haas, P. E. AU - van Soolingen, D. DA - Nov 15 ET - 11/09 J2 - American journal of epidemiology KW - Adult Age Factors Aged Cluster Analysis DNA Fingerprinting Female Humans Incidence Male Middle Aged *Models, Statistical Mycobacterium tuberculosis/genetics/*isolation & purification Netherlands/epidemiology Sex Factors Sputum/microbiology Time Factors Tuberculosis, Pulmonary/*epidemiology/genetics/*transmission LA - eng N1 - Borgdorff, M W Nagelkerke, N J de Haas, P E van Soolingen, D Am J Epidemiol. 2001 Nov 15;154(10):934-43. PY - 2001 RN - fulltext fulltext_1208 SN - 0002-9262 (Print) 0002-9262 (Linking) SP - 934-43 ST - Transmission of Mycobacterium tuberculosis depending on the age and sex of source cases T2 - Am J Epidemiol TI - Transmission of Mycobacterium tuberculosis depending on the age and sex of source cases UR - http://www.ncbi.nlm.nih.gov/pubmed/11700248http://aje.oxfordjournals.org/content/154/10/934.full.pdf VL - 154 ID - 2400 ER - TY - JOUR AB - CONTEXT: The rate of tuberculosis (TB) among US homeless persons may be 20 times that of the general adult population. Studies suggest that the majority of urban homeless TB cases are attributable to ongoing transmission of TB. Optimal TB-control strategies in both chronically and transiently homeless populations are not known. OBJECTIVE: To examine the effects of TB-control strategies on projected TB cases and deaths in US homeless populations using a computer-based simulation model. DESIGN, SETTING, AND POPULATION: The US general population and a theoretical population of 2 million homeless individuals in 1995 were divided into 18 clinical states based on the risk for or presence of TB and human immunodeficiency virus (HIV) infection in a semi-Markov model. MAIN OUTCOME MEASURES: Prevalence of transiently and chronically homeless individuals with active TB and deaths from TB as a function of public health measures taken to control and eliminate TB, including improvement of treatment effectiveness, improvement in access to treatment, and vaccination with BCG. RESULTS: A 10% increase in access to treatment among homeless persons with active TB produced larger declines in predicted TB cases and deaths after 10 years (cases and deaths among chronically homeless persons decreased 12.5% and 19.8% and among transiently homeless persons dropped 35.9% and 32.4%, respectively) than improvements in the effectiveness of treatment programs (cases and deaths among chronically homeless persons declined 7.2% and 3.1% and among transiently homeless persons dropped 10.9% and 4.1%, respectively). A 10% increase in access to treatment among homeless persons with latent TB infection led to a 6.7% decline in TB among chronically homeless persons and a 5.7% decline among transiently homeless persons, while a 10% improvement in effectiveness of treatment for latent TB infection was associated with declines of 3.0% and 3.3%, respectively. When treatment for latent TB infection was modeled to be the same in vaccinated and nonvaccinated populations, BCG vaccination led to TB case declines of 15.4% and 21.5% in chronically and transiently homeless populations, respectively. CONCLUSIONS: Overcoming barriers faced by homeless individuals in accessing TB treatment programs will be crucial to reducing the burden of TB in this high-risk group. Increased treatment access, improvement in the effectiveness of treatment programs, and BCG vaccination of HIV-negative homeless individuals have the best chance to markedly decrease TB morbidity and mortality. AD - Channing Laboratory, 181 Longwood Ave, Boston, MA 02115, USA. timothy.brewer@channing.harvard.edu AN - 11497538 AU - Brewer, T. F. AU - Heymann, S. J. AU - Krumplitsch, S. M. AU - Wilson, M. E. AU - Colditz, G. A. AU - Fineberg, H. V. DA - Aug 15 DO - jcu10000 [pii] DP - Nlm ET - 08/22 KW - Antitubercular Agents/therapeutic use BCG Vaccine Health Services Accessibility Homeless Persons/statistics & numerical data Humans Medically Uninsured Models, Theoretical Risk Tuberculosis/epidemiology/ prevention & control United States/epidemiology Vaccination LA - eng N1 - Brewer, T F Heymann, S J Krumplitsch, S M Wilson, M E Colditz, G A Fineberg, H V 1K08 AI01444-01A1/AI/NIAID NIH HHS/United States Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. United States JAMA : the journal of the American Medical Association JAMA. 2001 Aug 15;286(7):834-42. PY - 2001 RN - fulltext fulltext_1208 SN - 0098-7484 (Print) 0098-7484 (Linking) SP - 834-42 ST - Strategies to decrease tuberculosis in us homeless populations: a computer simulation model T2 - JAMA TI - Strategies to decrease tuberculosis in us homeless populations: a computer simulation model UR - http://jama.jamanetwork.com/article.aspx?articleid=194096 VL - 286 ID - 2401 ER - TY - JOUR AU - Feng, Z. AU - Huang, W. AU - Castillo-Chavez, C. PY - 2001 RN - fulltext fulltext_1208 SP - 425-452 ST - On the role of variable latent periods in mathematical models for tuberculosis T2 - Journal of Dynamics and Differential equations TI - On the role of variable latent periods in mathematical models for tuberculosis VL - 13 ID - 2403 ER - TY - JOUR AU - Jones, T. F. AU - Schaffner, W. DA - 2001 J2 - Am.J.Respir.Crit.Care Med. KW - case-finding cost effectiveness institutions prisons screening tuberculosis LB - 8818 N1 - TY - JOUR TB Tuberculosis control Case-finding No sub-heading PY - 2001 RN - fulltext fulltext_1208 SP - 77-81 ST - Miniature chest radiograph screening for tuberculosis in jails. A cost-effectiveness analysis TI - Miniature chest radiograph screening for tuberculosis in jails. A cost-effectiveness analysis VL - 164 ID - 2404 ER - TY - JOUR AB - Environmental control measures (ventilation, high-efficiency particulate air filtration, and upper room ultraviolet germicidal irradiation [UVGI]) are recommended to effectively control tuberculosis (TB) transmission from unsuspected TB patients in high-risk settings, but the effectiveness of their use is not often clear. This study presents a simulation model for a hypothetical hospital waiting room, in which the number of susceptible immunocompetent people in the waiting room follows a Poisson distribution (M = 5) in either low (annual number of TB patients = 5) or high TB risk settings (annual number of TB patients = 50), and used the model to evaluate the reduction of TB transmission risk by upper room UVGI. An exponential dose-response model was used for TB transmission and a two-zone model was used for evaluating the effect of upper room UVGI. Upper room UVGI reduced TB risk by 1.6-fold at 3 microW/cm2 UV irradiance in the upper room in the low TB risk setting and by 4.1-fold at 15 microW/cm2 UV irradiance in the upper room in the high TB risk setting. Use of upper room UVGI also reduced the mean annual new infection rate from 2.2 to 1.3 infections per year at 3 microW/cm2 and to 0.6 infections per year at 15 microW/cm2 in our hypothetical high-risk settings. The effect of upper room UVGI was sensitive to both vertical air velocity (air mixing) and UV irradiance level. Results from partitioning variability indicate that most variability of TB transmission risk came from waiting time in our hypothetical hospital. AD - Department of Environmental Health, Harvard School of Public Health, Boston, MA, USA. gko@email.unc.edu AN - 11726019 AU - Ko, G. AU - Burge, H. A. AU - Nardell, E. A. AU - Thompson, K. M. DA - Aug DP - Nlm ET - 12/01 KW - Computer Simulation Cost-Benefit Analysis Disease Transmission, Infectious/ prevention & control Environment, Controlled Health Facility Environment Humans Incidence Models, Theoretical Risk Tuberculosis/ epidemiology Ultraviolet Rays LA - eng N1 - Ko, G Burge, H A Nardell, E A Thompson, K M United States Risk analysis : an official publication of the Society for Risk Analysis Risk Anal. 2001 Aug;21(4):657-73. PY - 2001 RN - fulltext fulltext_1208 SN - 0272-4332 (Print) 0272-4332 (Linking) SP - 657-73 ST - Estimation of tuberculosis risk and incidence under upper room ultraviolet germicidal irradiation in a waiting room in a hypothetical scenario T2 - Risk Anal TI - Estimation of tuberculosis risk and incidence under upper room ultraviolet germicidal irradiation in a waiting room in a hypothetical scenario VL - 21 ID - 2405 ER - TY - JOUR AB - OBJECTIVE: The prompt diagnosis of smear-negative pulmonary tuberculosis (PTB) is a clinical challenge. It may be achieved by a number of tests which have varying accuracies, costs and degrees of invasiveness. The objective of this study was to compare the cost-effectiveness of clinical judgement (empirical), the Roche Cobas amplicor assay for Mycobacterium tuberculosis (amplicor), acid-fast staining of bronchoalveolar lavage specimens (BAL), nucleic acid amplification tests of bronchoalveloar lavage specimens for M. tuberculosis (BAL + NAA), computed tomography (CT) and amplicor assay followed by BAL. METHODOLOGY: The range of predictive values of the various strategies were derived from published data and a new study of 441 consecutive adult patients with suspected smear-negative PTB prospectively stratified into three pretest risk groups: low, intermediate and high. The cost-effectiveness was evaluated with a decision tree model (DATA software). RESULTS: The incidence of PTB was 5.7% (4% culture positive) for the whole group, 95% in the high-risk group, 0.9% in the low-risk group and 3.4% in the intermediate-risk group. The sensitivity of the empirical approach was 49% and of the amplicor assay was 44%. Patient outcomes were expressed as life expectancy for the base case of a 58-year-old man with a pretest probability of 5.7%. At this low pretest risk the differences in life expectancies between tests was < 0.1 years and the empirical approach incurred the lowest cost. Sensitivity analysis at increasing pretest risks showed better life expectancies (approximately 1 years) for CT scan and test combinations than empirical and amplicor for additional costs of US$243-US$309. Bronchoalveolar lavage had the worst overall cost-effectiveness. CONCLUSIONS: We conclude that the pretest risk of active PTB was a key determinant of test utility; that the AMPLICOR assay was comparable to clinical judgement; that BAL was the least useful test; and that with increasing risks, CT scan and test combinations performed better. Further studies are needed to better define patients with intermediate risk for PTB and to directly compare the cost-effectiveness of more sensitive nucleic acid amplification tests such as the enhanced Gen Probe, CT scan and test combinations/sequences in these patients. AD - Department of Medicine, National University of Singapore, Singapore. mdclimtk@nus.edu.sg AN - 11192555 AU - Lim, T. K. AU - Cherian, J. AU - Poh, K. L. AU - Leong, T. Y. DA - Dec ET - 02/24 KW - Bacteriological Techniques/economics/*standards *Bronchoalveolar Lavage Fluid Bronchoscopy/economics/*standards Cost-Benefit Analysis Decision Trees Humans Life Expectancy Male Middle Aged Nucleic Acid Amplification Techniques/economics/*standards Patient Selection Risk Factors Sensitivity and Specificity Sputum/*microbiology Tomography, X-Ray Computed/economics/*standards Tuberculosis, Pulmonary/*diagnosis/microbiology LA - eng N1 - Lim, T K Cherian, J Poh, K L Leong, T Y Case Reports Comparative Study Validation Studies Australia Respirology (Carlton, Vic.) Respirology. 2000 Dec;5(4):403-9. PY - 2001 RN - fulltext fulltext_1208 SN - 1323-7799 (Print) 1323-7799 (Linking) SP - 403-9 ST - The rapid diagnosis of smear-negative pulmonary tuberculosis: a cost-effectiveness analysis T2 - Respirology TI - The rapid diagnosis of smear-negative pulmonary tuberculosis: a cost-effectiveness analysis UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=11192555 VL - 5 ID - 2389 ER - TY - JOUR AB - This study examined whether costs associated with tuberculosis (TB) screening and directly observed preventive therapy (DOPT) among drug injectors attending a syringe exchange are justified by cases and costs of active TB cases prevented and examined the impact of monetary incentives to promote adherence on cost-effectiveness. We examined program costs and projected savings using observed adherence and prevalence rates and literature estimates of isoniazid (INH) preventive therapy efficacy, expected INH hepatoxicity rates, and TB treatment costs; we conducted sensitivity analyses for a range of INH effectiveness, chest X-ray (CXR) referral adherence, and different strategies regarding anergy among persons affected with human immunodeficiency virus (HIV). For 1,000 patients offered screening, incorporating real observed program adherence rates, the program would avert $179,934 in TB treatment costs, for a net savings of $123,081. Assuming a modest risk of TB among HIV-infected anergic persons, all strategies with regard to anergy were cost saving, and the strategy of not screening for anergy and not providing DOPT to HIV-infected anergic persons resulted in the greatest cost savings. If an incentive of $25 per person increased CXR adherence from the observed 31% to 50% or 100%, over a 5-year follow-up the net cost savings would increase to $170,054 and $414,856, respectively. In this model, TB screening and DOPT at a syringe exchange is a cost-effective intervention and is cost-saving compared to costs of treating active TB cases that would have occurred in the absence of the intervention. This model is useful in evaluating the cost impact of planned program refinements, which can then be tested. Monetary incentives for those referred for screening CXRs would be justified on a cost basis if they had even a modest beneficial impact on adherence. AD - Beth Israel Medical Center, First Avenue at 16th Street, New York City, NY 10003, USA. dperlman@bethisraelny.org AN - 11564856 AU - Perlman, D. C. AU - Gourevitch, M. N. AU - Trinh, C. AU - Salomon, N. AU - Horn, L. AU - Des Jarlais, D. C. DA - Sep DO - 10.1093/jurban/78.3.550 ET - 09/21 KW - AIDS-Related Opportunistic Infections/complications/diagnosis/prevention & control Adolescent Adult Antitubercular Agents/economics/therapeutic use/toxicity Cost-Benefit Analysis Female HIV Seropositivity Humans Incidence Isoniazid/economics/therapeutic use/toxicity Male Mass Screening/*economics Middle Aged *Needle-Exchange Programs New York City Substance Abuse, Intravenous/epidemiology Tuberculosis/*diagnosis/epidemiology/*prevention & control LA - eng N1 - Perlman, D C Gourevitch, M N Trinh, C Salomon, N Horn, L Des Jarlais, D C R01 DA9005/DA/NIDA NIH HHS/United States Research Support, U.S. Gov't, P.H.S. United States Journal of urban health : bulletin of the New York Academy of Medicine J Urban Health. 2001 Sep;78(3):550-67. PY - 2001 RN - fulltext fulltext_1208 SN - 1099-3460 (Print) 1099-3460 (Linking) SP - 550-67 ST - Cost-effectiveness of tuberculosis screening and observed preventive therapy for active drug injectors at a syringe-exchange program T2 - J Urban Health TI - Cost-effectiveness of tuberculosis screening and observed preventive therapy for active drug injectors at a syringe-exchange program UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=11564856http://www.springerlink.com/content/c7n6868776414512/fulltext.pdf VL - 78 ID - 2406 ER - TY - JOUR AB - HIV affects the pathogenesis and the transmission of Mycobacterium tuberculosis. We used a discrete event simulation model to predict the potential impact of HIV on increasing the probability and the expected severity of tuberculosis outbreaks. Our predictions reveal that an HIV epidemic can significantly increase the frequency and severity of tuberculosis outbreaks, but that this amplification effect of HIV on tuberculosis outbreaks is very sensitive to the tuberculosis treatment rate. At moderate or low treatment rates, even a moderate HIV epidemic can cause the average size of tuberculosis outbreaks to almost double in comparison with the expected outbreak size when HIV is absent. However, we determined that the amplification effect of HIV can be substantially reduced if the treatment rate of tuberculosis is very high. We discuss the significant implications of these results for the global control of tuberculosis. Our results also reveal that occasionally a "normal-virulence" strain of M. tuberculosis can be expected to generate a large outbreak. We discuss the implications of these results in understanding the virulence of M. tuberculosis and in the planned elimination of tuberculosis in the United States. AD - San Francisco Department of Public Health, San Francisco, California, USA. AN - 11744831 AU - Porco, T. C. AU - Small, P. M. AU - Blower, S. M. DA - Dec 15 DP - Nlm ET - 12/18 KW - Antitubercular Agents/therapeutic use Computer Simulation Disease Outbreaks HIV Infections/ epidemiology Humans Models, Biological Tuberculosis/drug therapy/ epidemiology/prevention & control United States LA - eng N1 - Porco, T C Small, P M Blower, S M AI35969/AI/NIAID NIH HHS/United States AI41935/AI/NIAID NIH HHS/United States DA10135/DA/NIDA NIH HHS/United States Research Support, U.S. Gov't, P.H.S. United States Journal of acquired immune deficiency syndromes (1999) J Acquir Immune Defic Syndr. 2001 Dec 15;28(5):437-44. PY - 2001 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1525-4135 (Print) 1525-4135 (Linking) SP - 437-44 ST - Amplification dynamics: predicting the effect of HIV on tuberculosis outbreaks T2 - J Acquir Immune Defic Syndr TI - Amplification dynamics: predicting the effect of HIV on tuberculosis outbreaks VL - 28 ID - 2407 ER - TY - JOUR AB - BACKGROUND: The international controversy surrounding the use and effectiveness of the Bacillus Calmette-Guerin (BCG) vaccine and the low incidence of tuberculosis (TB) among Japanese children prompted this study. METHODS: We compared 'universal BCG vaccination' with 'no vaccination at all' using a cost-effectiveness analysis. The study population was a hypothetical cohort comprising a total of 1.2 million infants born in 1996 at locations all over Japan. A model was developed to calculate the number of TB cases prevented by the vaccination programme. Assuming 40-80% overall vaccine efficacy (64-86% for TB-meningitis) and 10 years of protection, we calculated the cost and number of immunizations required to prevent one child from developing TB, the total number of TB cases averted by vaccination and total costs required for the programme. RESULTS: Based on an assumption of flexible vaccine efficacy (40-80%), we estimated that 111-542 TB cases including 10-27 of TB-meningitis would be prevented during the 10 years after BCG vaccination among the cohort of infants born in 1996. About US$35 950-175 862 or 2125-10 399 immunizations would be required to prevent one child from developing TB. Sensitivity analyses covering a wide duration of protection, incidence of TB, vaccine coverage and discount rate, revealed that other than vaccine efficacy, the cost of preventing a single case of TB is highly sensitive to the duration of BCG protection and TB incidence. CONCLUSION: The cost per case of TB prevented is heavily dependent on vaccine efficacy and the duration of protection, and is high compared with the cost of treating one child who has developed TB. AD - Department of General Medicine and Clinical Epidemiology, Kyoto University Graduate School of Medicine, Kyoto, Japan. AN - 11369746 AU - Rahman, M. AU - Sekimoto, M. AU - Takamatsu, I. AU - Hira, K. AU - Shimbo, T. AU - Toyoshima, K. AU - Fukui, T. DA - Apr J2 - International journal of epidemiology KW - BCG Vaccine/adverse effects/*economics Child Child, Preschool Cost-Benefit Analysis *Health Planning Humans Immunization Programs/*economics Infant Japan/epidemiology Models, Econometric Tuberculosis/epidemiology/mortality/*prevention & control LA - eng N1 - Comparative Study Journal Article Research Support, Non-U.S. Gov't England PY - 2001 RN - fulltext fulltext_1208 SN - 0300-5771 (Print) SP - 380-385 ST - Economic evaluation of universal BCG vaccination of Japanese infants T2 - Int J Epidemiol TI - Economic evaluation of universal BCG vaccination of Japanese infants UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=11369746 VL - 30 ID - 2408 ER - TY - JOUR AB - This paper documents and attempts to explain the epidemic spread of tuberculosis (TB) in Russia during the 1990s. After several decades of decline, the notification rate of all new TB cases among permanent residents increased by 7.5% per year from 1991-1999 and the death rate by 11% per year. Growth was quickest from 1993-1995 but increased again after the economic crisis of August 1998. Approximately 120 000 new cases and 30 000 deaths were reported in 1999. Case detection and cure rates have fallen in Russia since the mid-1980s; the fall has been accompanied by a higher frequency of severe disease among cases, and higher death and case fatality rates. With a mathematical model describing the deterioration in case finding and cure rates we could replicate the average rate of increase in incidence 1991-1999 but not the precise timing of the observed changes. Other factors that probably helped to shape the observed rise in caseload include enhanced transmission due to the mixing of prison and civilian populations, an increase in susceptibility to disease, and changes in the proportion of cases detected by surveillance. Although our explanation for the resurgence of TB is incomplete, we have identified a set of measures that can be implemented now to cut transmission, incidence and deaths. AD - Department of Epidemiology and Antituberculosis Care Organization, Research Institute of Phthisiopulmonology, I. M. Setchenov Medical Academy, 4 Dostoevsky Street, 101478 Moscow, Russian Federation. AN - 11516384 AU - Shilova, M. V. AU - Dye, C. DA - Jul 29 DO - 10.1098/rstb.2001.0895 [doi] DP - Nlm ET - 08/23 KW - Humans Prevalence Prisons Quality of Health Care Russia/epidemiology Survival Rate Treatment Outcome Tuberculosis/drug therapy/ epidemiology LA - eng N1 - Shilova, M V Dye, C Research Support, Non-U.S. Gov't England Philosophical transactions of the Royal Society of London. Series B, Biological sciences Philos Trans R Soc Lond B Biol Sci. 2001 Jul 29;356(1411):1069-75. PY - 2001 RN - fulltext fulltext_1208 SN - 0962-8436 (Print) 0962-8436 (Linking) SP - 1069-75 ST - The resurgence of tuberculosis in Russia T2 - Philos Trans R Soc Lond B Biol Sci TI - The resurgence of tuberculosis in Russia UR - http://rstb.royalsocietypublishing.org.ez.lshtm.ac.uk/content/356/1411/1069.full.pdf VL - 356 ID - 2409 ER - TY - JOUR AB - Though it is recognized that the extent of 'clustering' of isolates from tuberculosis cases in a given population is related to the amount of disease attributable to recent transmission, the relationship between the two statistics is poorly understood. Given age-dependent risks of disease and the fact that a long study (e.g. spanning several years) is more likely to identify transmission-linked cases than a shorter study, both measures, and thus the relationship between them, probably depend strongly on the ages of the cases ascertained and study duration. The contribution of these factors is explored in this paper using an age-structured model which describes the introduction and transmission of M. tuberculosis strains with different DNA fingerprint patterns in The Netherlands during this century, assuming that the number of individuals contacted by each case varies between cases and that DNA fingerprint patterns change over time through random mutations, as observed in several studies. Model predictions of clustering in different age groups and over different time periods between 1993 and 1997 compare well against those observed. According to the model, the proportion of young cases with onset in a given time period who were 'clustered' underestimated the proportion of disease attributable to recent transmission in this age group (by up to 25% in males); for older individuals, clustering overestimated this proportion. These under- and overestimates decreased and increased respectively as the time period over which the cases were ascertained increased. These results have important implications for the interpretation of estimates of the proportion of disease attributable to recent transmission, based on 'clustering' statistics, as are being derived from studies of the molecular epidemiology of tuberculosis in many populations. AD - Department of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine. AN - 11293682 AU - Vynnycky, E. AU - Nagelkerke, N. AU - Borgdorff, M. W. AU - van Soolingen, D. AU - van Embden, J. D. AU - Fine, P. E. KW - Adolescent Adult Age Factors Aged Child Child, Preschool Cluster Analysis *DNA Fingerprinting Epidemiology, Molecular Female Human Infant Infant, Newborn Life Style Longitudinal Studies Male Middle Age Models, Biological Mutation Mycobacterium tuberculosis/*classification/genetics/isolation & purification Netherlands Support, Non-U.S. Gov't Time Factors Tuberculosis/epidemiology/prevention & control/*transmission PY - 2001 RN - fulltext fulltext_1208 SP - 43-62. ST - The effect of age and study duration on the relationship between 'clustering' of DNA fingerprint patterns and the proportion of tuberculosis disease attributable to recent transmission T2 - Epidemiol Infect TI - The effect of age and study duration on the relationship between 'clustering' of DNA fingerprint patterns and the proportion of tuberculosis disease attributable to recent transmission UR - http://www.ncbi.nlm.nih.gov/htbin-post/Entrez/query?db=m&form=6&dopt=r&uid=11293682http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2869673/pdf/11293682.pdf VL - 126 ID - 2410 ER - TY - JOUR AB - A key issue for the study of tuberculosis infection (TB) is to understand why individuals infected with Mycobacterium tuberculosis experience different clinical outcomes. Elaborating the immune mechanisms that determine whether an infected individual will suffer active TB or latent infection can aid in developing treatment and prevention strategies. To better understand the dynamics of M. tuberculosis infection and immunity, we have developed a virtual human model that qualitatively and quantitatively characterizes the cellular and cytokine control network operational during TB infection. Using this model, we identify key regulatory elements in the host response. In particular, factors affecting cell functions, such as macrophage activation and bactericidal capabilities, and effector T cell functions such as cytotoxicity and cytokine production can each be determinative. The model indicates, however, that even if latency is achieved, it may come at the expense of tissue damage if the response is not properly regulated. A balance in Th1 and Th2 immune responses governed by IFN-gamma, IL-10, and IL-4 facilitate this down-regulation. These results are further explored through virtual deletion and depletion experiments. AD - Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109, USA. AN - 11160244 AU - Wigginton, J. E. AU - Kirschner, D. KW - Acute Disease Animals Disease Progression Humans Immunity, Cellular Interleukin-10/biosynthesis/deficiency/genetics Macrophage Activation/genetics/immunology Macrophages/*immunology/metabolism/microbiology Mice Mice, Knockout *Models, Immunological Mycobacterium tuberculosis/growth & development/*immunology Sequence Deletion Tuberculosis/etiology/*immunology/microbiology/prevention & control LA - eng N1 - Wigginton, J E Kirschner, D HL62119-01/HL/NHLBI NIH HHS/United States Comparative Study Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. United States Journal of immunology (Baltimore, Md. : 1950) J Immunol. 2001 Feb 1;166(3):1951-67. PY - 2001 RN - fulltext fulltext_1208 SN - 0022-1767 (Print) 0022-1767 (Linking) SP - 1951-1967 ST - A model to predict cell-mediated immune regulatory mechanisms during human infection with Mycobacterium tuberculosis T2 - Journal of Immunology TI - A model to predict cell-mediated immune regulatory mechanisms during human infection with Mycobacterium tuberculosis UR - http://www.ncbi.nlm.nih.gov/pubmed/11160244http://www.jimmunol.org/content/166/3/1951.full.pdf VL - 166 ID - 2411 ER - TY - JOUR AB - The risk of developing active tuberculosis is highest within the first 2 years of infection. Therefore, an intervention that targets persons with recent infection, such as identifying contacts of active cases, could be particularly effective as an epidemic control measure. A mathematical model of a tuberculosis epidemic is formulated and used to evaluate the strategy of targeting therapy to persons with recently acquired latent tuberculosis infection. The model is used to quantify the effectiveness of therapy for early latent tuberculosis infection in reducing the prevalence of active tuberculosis. The model is also used to demonstrate how effective therapy for early latent tuberculosis infection has to be to eliminate tuberculosis, when used in conjunction with therapy for active tuberculosis. Analysis of the model suggests that programs such as contact investigations, which identify and treat persons recently infected with Mycobacterium tuberculosis, may have a substantial effect on controlling tuberculosis epidemics. AD - Department of Medicine, Veterans' Affairs Medical Center, San Francisco 94121, USA. eziv@itsa.ucsf.edu AN - 11207156 AU - Ziv, E. AU - Daley, C. L. AU - Blower, S. M. DA - Feb 15 ET - 02/24 J2 - American journal of epidemiology KW - Antitubercular Agents/therapeutic use Humans *Models, Theoretical Mycobacterium tuberculosis/isolation & purification Risk Factors Time Factors Treatment Outcome Tuberculosis/*drug therapy/epidemiology/prevention & control LA - eng M3 - Research Support, U.S. Gov't, Non-P.H.S. Research Support, U.S. Gov't, P.H.S. N1 - Ziv, E Daley, C L Blower, S M R01-AI41935/AI/NIAID NIH HHS/ Am J Epidemiol. 2001 Feb 15;153(4):381-5. PY - 2001 RN - fulltext fulltext_1208 SN - 0002-9262 (Print) 0002-9262 (Linking) SP - 381-5 ST - Early therapy for latent tuberculosis infection T2 - Am J Epidemiol TI - Early therapy for latent tuberculosis infection UR - http://www.ncbi.nlm.nih.gov/pubmed/11207156http://aje.oxfordjournals.org/content/153/4/381.full.pdf VL - 153 ID - 2413 ER - TY - JOUR AB - Abrupt changes in environmental conditions--broadly understood to include demographic and social dynamics--can seriously impact the local or global disease dynamics of a population. These changes in the evolutionary landscape, which may occur over relatively short time-scales, are very likely to play a critical role in disease evolution. The potential impact of demographic, social and epidemiological shifts on the evolution of tuberculosis epidemics in the United States over the past century and a half is the main subject of this article. Evidence is provided to support the hypothesis that the observed substantial decreases in the incidence of active tuberculosis are the result of abrupt reductions in the rates of disease progression. AD - Department of Biometrics & Mathematical and Theoretical Biology Institute, Cornell University, 431 Warren Hall, Ithaca, NY 14853-7801, USA. jpa9@cornell.edu AN - 12051976 AU - Aparicio, J. P. AU - Capurro, A. F. AU - Castillo-Chavez, C. DA - Mar 21 DO - 10.1006/jtbi.2001.2489 [doi] S0022519301924890 [pii] DP - Nlm ET - 06/08 KW - Disease Outbreaks Disease Progression Humans Life Style Models, Statistical Nutritional Physiological Phenomena Prevalence Social Environment Tuberculosis/ epidemiology/microbiology/transmission United States/epidemiology Urbanization LA - eng N1 - Aparicio, Juan P Capurro, AngelL F Castillo-Chavez, Carlos Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. England Journal of theoretical biology J Theor Biol. 2002 Mar 21;215(2):227-37. PY - 2002 RN - fulltext fulltext_1208 SN - 0022-5193 (Print) 0022-5193 (Linking) SP - 227-37 ST - Markers of disease evolution: the case of tuberculosis T2 - J Theor Biol TI - Markers of disease evolution: the case of tuberculosis UR - http://ac.els-cdn.com/S0022519301924890/1-s2.0-S0022519301924890-main.pdf?_tid=248e607c3524c38ff4ea031877b0a45e&acdnat=1345011913_2c141ed2452b2d827ae048d90a11fd90 VL - 215 ID - 2414 ER - TY - JOUR AB - OBJECTIVE: The annual risk of infection (ARI) for tuberculosis is the probability that an individual without previous contact with the tubercle bacillus has of being infected during the course of a year. The ARI is the most appropriate indicator for estimating the degree of tuberculosis infection in a population. The objective of this paper was to estimate the ARI and its trends in the city of Cali, Colombia, using data provided by the Municipal Secretariat of Health. METHODS: We used a deterministic model of the dynamics of pulmonary tuberculosis. The flows among the population subgroups were based on the natural history of the disease, taking vaccination into account. Using the data from the Municipal Secretariat of Health, we estimated the initial conditions and the values of the parameters. RESULTS: The mean ARI values were 1.24% in the 1970s, 0.93% in the 1980s, and 0.85% in the 1990s. In order to assess trends, we attempted to predict the annual risk, utilizing a nonlinear least-squares adjustment of the data on the overall percentage for each year. With that approach, we projected that the ARI in 2003 would be 1.3%, indicating a return to the patterns found in the 1970s. CONCLUSIONS: The estimated risk of tuberculosis infection in Cali during the decades of the 1970s, the 1980s, and the 1990s was very high in comparison with the risk in countries such as the Netherlands, which in 1985 had an ARI of 0.012%. However, the ARI in Cali is not so high in comparison to indices for other countries of South America, which range from 0.5% to 1.5%. This model and the simulation it produced showed a rising trend in the ARI for Cali, as well as demonstrated that the ARI will tend to continue to rise if control measures are not improved. AD - Universidad Autonoma de Occidente, Departamento de Ciencias Basicas, Calle 25 No. 115-85, Cali, Colombia. AN - 11998182 AU - de la Pava, E. AU - Salguero, B. AU - Alzate, A. DA - Mar J2 - Revista panamericana de salud publica = Pan American journal of public health KW - Colombia Humans *Models, Statistical Risk Assessment Time Factors Tuberculosis/*epidemiology LA - spa N1 - English Abstract Journal Article United States OP - Modelo matematico del riesgo anual de infeccion tuberculosa en Cali. PY - 2002 RN - fulltext fulltext_1208 SN - 1020-4989 (Print) SP - 166-171 ST - [A mathematical model of the annual risk of tuberculosis infection in Cali, Colombia] T2 - Rev Panam Salud Publica TI - [A mathematical model of the annual risk of tuberculosis infection in Cali, Colombia] UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=11998182 VL - 11 ID - 2415 ER - TY - JOUR AB - The discovery of high prevalences of antibiotic resistance in some pathogens, in some parts of the world, has provoked fears of a widespread loss of drug efficacy. Here, we use a mathematical model to investigate the evolution of resistance to four major anti-tuberculosis drugs (isoniazid, rifampicin, ethambutol and streptomycin) in 47 sites around the world. The model provides a new method of estimating the relative risk of treatment failure for patients carrying drug-resistant strains and the proportion of patients who develop resistance after failing treatment. Using estimates of these two quantities together with other published data, we reconstructed the epidemic spread of isoniazid resistance over the past 50 years. The predicted median prevalence of resistance among new cases today was 7.0% (range 0.9-64.3%), close to the 6.3% (range 0-28.1%) observed. Predicted and observed prevalences of resistance to isoniazid plus rifampicin (multidrug-resistant or MDR-TB) after 30 years of combined drug use were also similar, 0.9% (0.1-5.9%) and 1.0% (range 0-14.1%), respectively. With current data, and under prevailing treatment practices, it appears that MDR-TB will remain a localized problem, rather than becoming a global obstacle to tuberculosis control. To substantiate this result, further measurements are needed of the relative fitness of drug-resistant strains. AD - Communicable Diseases, World Health Organization, Geneva, Switzerland. dyec@who.int AN - 12123297 AU - Dye, C. AU - Espinal, M. A. DA - Jan 7 DO - 10.1098/rspb.2000.1328 [doi] DP - Nlm ET - 07/19 KW - Antitubercular Agents/ pharmacology Drug Resistance, Multiple, Bacterial Humans Isoniazid/pharmacology Microbial Sensitivity Tests Models, Biological Mycobacterium tuberculosis/ drug effects Prevalence Rifampin/pharmacology Treatment Failure Tuberculosis, Multidrug-Resistant/drug therapy/ epidemiology/microbiology Tuberculosis, Pulmonary/drug therapy/ epidemiology/microbiology L1 - internal-pdf://0211382621/Dye-2002-Will tuberculosis become resistant to.pdf LA - eng N1 - Dye, C Espinal, M A England Proceedings. Biological sciences / The Royal Society Proc Biol Sci. 2001 Jan 7;268(1462):45-52. PY - 2002 RN - fulltext fulltext_1208 SN - 0962-8452 (Print) 0962-8452 (Linking) SP - 45-52 ST - Will tuberculosis become resistant to all antibiotics? T2 - Proc Biol Sci TI - Will tuberculosis become resistant to all antibiotics? UR - http://rspb.royalsocietypublishing.org.ez.lshtm.ac.uk/content/268/1462/45.full.pdf http://rspb.royalsocietypublishing.org/content/royprsb/268/1462/45.full.pdf VL - 268 ID - 2402 ER - TY - JOUR AU - Feng, Z. AU - Iannelli, M. AU - Milner, F. A. PY - 2002 SP - 1634-1656 ST - A two-strain tuberculosis model with age of infection T2 - SIAM J Appl Math TI - A two-strain tuberculosis model with age of infection VL - 62 ID - 3946 ER - TY - JOUR AB - Studies of early bactericidal activity (EBA) are important in the rapid evaluation of new antituberculosis drugs. Historically, these have concentrated on the log fall in the viable count in sputum during the first 48 hours of therapy. In this paper, we provide a mathematical model that suggests that the viable count in sputum follows an exponential decay curve with the equation V = S + Me(-kt) (where V is the viable count, M the population of bacteria susceptible to the test drug, S the population susceptible only to sterilizing agents, t the day of sputum collection as related to start of therapy, k the rate constant for the bacteria killed each day, and e the Napierian constant). We demonstrate that data from clinical trials fits the exponential decay model. We propose that future EBA studies should be performed by measuring daily quantitative counts for at least 5 days. We also propose that the comparison of the early bactericidal activity of antituberculosis drugs should be evaluated using the time taken to reduce the viable count by 50% (vt(50)). A further reiterative refinement following a rule set based on statistically the best fit to the exponential decay model is described that will allow investigators to identify anomalous results and thus enhance the accuracy in measuring early bactericidal activity. AD - Academic Department of Medical Microbiology, Royal Free and University College Medical School, London, United Kingdom. stepheng@rfc.ucl.ac.uk AN - 12091167 AU - Gillespie, S. H. AU - Gosling, R. D. AU - Charalambous, B. M. DA - Jul 1 DP - Nlm ET - 07/02 KW - Anti-Infective Agents/pharmacology Antitubercular Agents/ pharmacology Ciprofloxacin/pharmacology Clinical Trials as Topic/statistics & numerical data Colony Count, Microbial Drug Evaluation/ statistics & numerical data Humans Isoniazid/pharmacology Models, Biological Mycobacterium tuberculosis/ drug effects Regression Analysis Sputum/microbiology Tuberculosis, Pulmonary/ drug therapy LA - eng N1 - Gillespie, Stephen H Gosling, Roland D Charalambous, Bambos M Research Support, Non-U.S. Gov't United States American journal of respiratory and critical care medicine Am J Respir Crit Care Med. 2002 Jul 1;166(1):31-5. PY - 2002 RN - fulltext fulltext_1208 SN - 1073-449X (Print) 1073-449X (Linking) SP - 31-5 ST - A reiterative method for calculating the early bactericidal activity of antituberculosis drugs T2 - Am J Respir Crit Care Med TI - A reiterative method for calculating the early bactericidal activity of antituberculosis drugs UR - http://ajrccm.atsjournals.org/content/166/1/31.full.pdf VL - 166 ID - 2417 ER - TY - JOUR AD - Fac Ciencias Lisboa, DBV, P-1749016 Lisbon, Portugal. Ctr Matemat & Aplicacoes Fundamentais, P-1649003 Lisbon, Portugal. Gomes, MC (reprint author), Fac Ciencias Lisboa, DBV, Bloco C2,Piso 4,Campo Grande, P-1749016 Lisbon, Portugal. AN - WOS:000172946800008 AU - Gomes, M. C. AU - Margheri, A. AU - Rebelo, C. DA - Feb DO - 10.1016/s0362-546x(00)00211-x IS - 4 J2 - Nonlinear Anal.-Theory Methods Appl. KW - tuberculosis bifurcation stability persistence epidemiology mortality Mathematics LA - English M3 - Article N1 - ISI Document Delivery No.: 506AB Times Cited: 2 Cited Reference Count: 27 Gomes, MC Margheri, A Rebelo, C Rebelo, Carlota/M-2582-2015; Margheri, Alessandro/M-8717-2015; Gomes, Manuel/F-9633-2011 Rebelo, Carlota/0000-0001-5818-8892; Margheri, Alessandro/0000-0001-6475-3405; Gomes, Manuel/0000-0002-2679-0974 2 0 3 Pergamon-elsevier science ltd Oxford PY - 2002 SN - 0362-546X SP - 617-636 ST - Stability and persistence in a compartment model of pulmonary tuberculosis T2 - Nonlinear Analysis-Theory Methods & Applications TI - Stability and persistence in a compartment model of pulmonary tuberculosis UR - ://WOS:000172946800008 VL - 48 ID - 6263 ER - TY - JOUR AB - Optimal control theory is applied to a system of ordinary differential equations modeling a two-strain tuberculosis model. Seeking to reduce the latent and infectious groups with the resistant-strain tuberculosis, we use controls representing two types of treatments. The optimal controls are characterized in terms of the optimality system, which is solved numerically for several scenarios. AD - Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA Univ Tennessee, Dept Math, Knoxville, TN 37996 USA Purdue Univ, Dept Math, W Lafayette, IN 47907 USA AN - WOS:000178082300001 AU - Jung, E. AU - Lenhart, S. AU - Feng, Z. DA - Nov IS - 4 J2 - Discrete Cont Dyn-B KW - mathematical model tuberculosis optimal control antibiotic resistance strategies LA - English N1 - 594zl Times Cited:111 Cited References Count:15 PY - 2002 SN - 1531-3492 SP - 473-482 ST - Optimal control of treatments in a two-strain tuberculosis model T2 - Discrete and Continuous Dynamical Systems-Series B TI - Optimal control of treatments in a two-strain tuberculosis model UR - ://WOS:000178082300001 VL - 2 ID - 4831 ER - TY - JOUR AB - The effects of standard patterns of population growth in blended SI-SEI models (of which models for 'fast and slow' tuberculosis are an instance) are considered. When the incidence has the 'true mass action' form, the system is globally stable under both exponential and logistic population dynamics, whereas sustained oscillations occur in the case of bilinear incidence. This shows in the final analysis, the minimal dynamical ingredients needed to generate oscillations in basic epidemiological models: provided the population is exponentially growing and the incidence is bilinear, at least a fraction of the newly exposed individuals must enter the infective state with a delay. AD - Dipartimento Stat & Mat Applicata Econ, I-56124 Pisa, Italy Dipartimento Sci Econ & Metodi Quantitat, I-28100 Novara, Italy AN - WOS:000181449600002 AU - Manfredi, P. AU - Salinelli, E. DA - Jun IS - 2 J2 - Ima J Math Appl Med KW - basic epidemiological models exponential and logistic population dynamics sustained oscillations dependent death rate epidemic models tuberculosis LA - English N1 - 653qy Times Cited:6 Cited References Count:20 PY - 2002 SN - 0265-0746 SP - 95-111 ST - Population-induced oscillations in blended SI-SEI epidemiological models T2 - Ima Journal of Mathematics Applied in Medicine and Biology TI - Population-induced oscillations in blended SI-SEI epidemiological models UR - ://WOS:000181449600002 VL - 19 ID - 4832 ER - TY - JOUR AB - A population model for the transmission dynamics of tuberculosis (TB) which incorporates a preventive vaccine and an effective therapeutic treatment is analysed qualitatively. The existence and uniqueness of the associated endemic equilibrium are discussed. By constructing a Lyapunov function, the global stability of the disease-free equilibrium of the model is established. The stability analysis of the diseasefree equilibrium reveals that the disease dynamics depends on a threshold quantity called the basic reproduction number (R0) such that the disease will be eradicated from the community if R0 < 1 and it persists if R0 > 1. The model is adapted and used to study the case where no preventive vaccine is administered. In addition to establishing the global stability of the vaccination-free model, the optimal treatment rate needed for disease eradication is determined. The vaccination-free model is then extended to monitor the effect of exogenous re-infection in the transmission dynamics of TB. Our analysis shows that the vaccination-free model with exogenous re-infection may undergo the phenomenon of bistability where a stable endemic equilibrium can co-exist with the stable disease-free equilibrium when R0 < 1. This shows that, unlike in the case without exogenous re-infection, reducing R0 to values less than unity may fail to eradicate the disease. AU - Moghadas, S. M. AU - Gumbo, A. B. IS - 3 PY - 2002 SP - 411-428 ST - ANALYSIS OF A MODEL FOR TRANSMISSION DYNAMICS OF TB T2 - Canadian Applied Mathematics Quarterly TI - ANALYSIS OF A MODEL FOR TRANSMISSION DYNAMICS OF TB UR - http://ami.math.ualberta.ca/CAMQ/pdf_files/vol_10/10_3/10_3e.pdf VL - 10 ID - 4937 ER - TY - JOUR AB - There is wide variation in endemic tuberculosis (TB) levels between countries and we seek to identify possible causes of these differences. In this study we present an epidemiological model of Mycobacterium tuberculosis infection to investigate the effects of host genetics and demographic factors on epidemic TB. We discuss the general framework for this approach and present analytical results to identify important parameters affecting steady-state prevalence and incidence rates of TB disease. We then use numerical simulations of our model to observe the effects of a genetically susceptible subpopulation on TB disease dynamics at the population level. Finally, we simulate infection within a genetically heterogeneous population in two demographic settings: India (a typical population with high TB prevalence) and the USA (a typical population with low TB prevalence). Results show that changes in transmission parameters, the fraction of the population genetically susceptible to infection, and demographic factors strongly affect TB prevalence and incidence rates. AD - Department of Microbiology and Immunology, The University of Michigan Medical School, Ann Arbor, MI 48109-0620, USA. AN - 12387922 AU - Murphy, B. M. AU - Singer, B. H. AU - Anderson, S. AU - Kirschner, D. DA - Nov-Dec DO - S0025556402001335 [pii] DP - Nlm ET - 10/22 KW - Computer Simulation Demography Disease Outbreaks Genetic Predisposition to Disease Humans India/epidemiology Models, Theoretical Tuberculosis/ epidemiology/genetics/immunology/transmission United States/epidemiology LA - eng N1 - Murphy, Brian M Singer, Benjamin H Anderson, Shoana Kirschner, Denise 5 T32 AI07528/AI/NIAID NIH HHS/United States R01 HL62119/HL/NHLBI NIH HHS/United States Comparative Study Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. United States Mathematical biosciences Math Biosci. 2002 Nov-Dec;180:161-85. PY - 2002 RN - fulltext fulltext_1208 SN - 0025-5564 (Print) 0025-5564 (Linking) SP - 161-85 ST - Comparing epidemic tuberculosis in demographically distinct heterogeneous populations T2 - Math Biosci TI - Comparing epidemic tuberculosis in demographically distinct heterogeneous populations UR - http://ac.els-cdn.com/S0025556402001335/1-s2.0-S0025556402001335-main.pdf?_tid=c442474c03637019ddb7f06fa7db5546&acdnat=1345012736_fe7a70aea1d9e14e5fc4f705b497ddf7 VL - 180 ID - 2418 ER - TY - JOUR AB - Recently developed molecular techniques have revolutionized the epidemiology of tuberculosis. Multiple studies have used these tools to examine the population structure of Mycobacterium tuberculosis isolates in different communities. The distributions of clusters of M. tuberculosis isolates in these settings may variously reflect social mixing patterns or the differential fitness of specific clones of the organism. We developed an individual-based microsimulation of tuberculosis transmission to explore social and demographic determinants of cluster distribution and to observe the effect of transmission dynamics on the empiric data from molecular epidemiologic studies. Our results demonstrate that multiple host-related factors contribute to wide variation in cluster distributions even when all strains of the organism are assumed to be equally transmissible. These host characteristics include interventions such as chemotherapy, vaccination and chemoprophylaxis, HIV prevalence, the age structure of the population, and the prevalence of latent tuberculosis infection. We consider the implications of these results for the interpretation of cluster studies of M. tuberculosis as well as the more general application of microsimulation models to infectious disease epidemiology. AD - Department of Epidemiology, Harvard School of Public Health and Infectious Disease Unit, Massachusetts General Hospital, 677 Huntington Avenue, Boston, MA, 02115, USA. mmurray@hsph.harvard.edu AN - 11818527 AU - Murray, M. DA - Feb 5 DO - 10.1073/pnas.022618299 ET - 01/31 J2 - Proceedings of the National Academy of Sciences of the United States of America KW - Cluster Analysis HIV Infections/epidemiology Humans Incidence Molecular Epidemiology Mycobacterium tuberculosis/*genetics Netherlands/epidemiology Prevalence Prisoners/statistics & numerical data Tuberculosis/*epidemiology/transmission United States/epidemiology LA - eng M3 - Comparative Study Research Support, U.S. Gov't, P.H.S. N1 - Murray, Megan PY - 2002 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 0027-8424 (Print) 0027-8424 (Linking) SP - 1538-43 ST - Determinants of cluster distribution in the molecular epidemiology of tuberculosis T2 - Proc Natl Acad Sci U S A TI - Determinants of cluster distribution in the molecular epidemiology of tuberculosis UR - http://www.ncbi.nlm.nih.gov/pubmed/11818527http://www.ncbi.nlm.nih.gov/pmc/articles/PMC122226/pdf/pq0302001538.pdf VL - 99 ID - 2419 ER - TY - JOUR AB - Among the goals of the molecular epidemiology of infectious disease are to quantify the extent of ongoing transmission of infectious agents and to identify host- and strain-specific risk factors for disease spread. I demonstrate the potential bias in estimates of recent transmission and the impact of risk factors for clustering by using computer simulations to reconstruct populations of tuberculosis patients and sample from them. The bias consistently results in underestimating recent transmission and the impact of risk factors for recent transmission. AD - Department of Epidemiology, Harvard School of Public Health, Boston, Massachussetts 02115, USA. mmurray@hsph.harvard.edu AN - 11971768 AU - Murray, M. DA - Apr DO - 10.3201/eid0804.000444 [doi] DP - Nlm ET - 04/25 KW - Algeria/epidemiology Computer Simulation Humans Molecular Epidemiology/ methods Monte Carlo Method Mycobacterium tuberculosis/isolation & purification Netherlands/epidemiology Odds Ratio Risk Factors Selection Bias Sudan/epidemiology Tuberculosis/ epidemiology/ transmission United States/epidemiology LA - eng N1 - Murray, Megan K08 A1-01430-01/PHS HHS/United States Research Support, U.S. Gov't, P.H.S. United States Emerging infectious diseases Emerg Infect Dis. 2002 Apr;8(4):363-9. PY - 2002 RN - fulltext fulltext_1208 SN - 1080-6040 (Print) 1080-6040 (Linking) SP - 363-9 ST - Sampling bias in the molecular epidemiology of tuberculosis T2 - Emerg Infect Dis TI - Sampling bias in the molecular epidemiology of tuberculosis VL - 8 ID - 2420 ER - TY - JOUR AB - SETTING: England and Wales. OBJECTIVE: To quantify the relative contribution of vaccination, chemotherapy and preventive therapy to the reduction in tuberculosis incidence in England and Wales between 1953 and 1990. DESIGN: A compartmental model of tuberculosis transmission was fitted to notification data between 1913 and 1939 to estimate pre-vaccination parameters. Best-fit estimates of the rates of chemotherapy and preventive therapy were derived by fitting the model to notification data between 1953 and 1990. Published vaccination rates were used. MAIN OUTCOME MEASURE: Number of cases of pulmonary tuberculosis averted. RESULTS: The numbers of respiratory tuberculosis cases averted between 1953 and 1990 by the use of preventive therapy, vaccination and chemotherapy were 288318, 57085 and 206996, respectively. CONCLUSIONS: Of those interventions considered, preventive therapy has the greatest impact on transmission. The duration of infectiousness is long, with an onset that is likely to pre-date sputum positivity. AD - Division of Primary Care and Population Health Sciences, Imperial College School of Medicine at St. Mary's, London, United Kingdom. RPitman@phls.org.uk AN - 12068980 AU - Pitman, R. AU - Jarman, B. AU - Coker, R. DA - Jun KW - *Antibiotic Prophylaxis Antitubercular Agents/*therapeutic use England/epidemiology Humans Incidence Intervention Studies *Models, Theoretical *Preventive Medicine Program Evaluation Research Support, Non-U.S. Gov't Tuberculosis Vaccines/*therapeutic use Tuberculosis, Pulmonary/*prevention & control/*transmission Wales/epidemiology N1 - 1027-3719 (Print) Journal Article PY - 2002 RN - fulltext fulltext_1208 SP - 485-491 ST - Tuberculosis transmission and the impact of intervention on the incidence of infection T2 - International Journal of Tuberculosis and Lung Disease TI - Tuberculosis transmission and the impact of intervention on the incidence of infection UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=12068980 VL - 6 ID - 2421 ER - TY - JOUR AU - Raimundo, Silvia Martorano AU - Yang, Hyun Mo AU - Bassanezi, Rodney Carlos AU - Ferreira, Marizete A. C. DO - doi:10.1142/S0218339002000457 PY - 2002 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SP - 61-83 ST - THE ATTRACTING BASINS AND THE ASSESSMENT OF THE TRANSMISSION COEFFICIENTS FOR HIV AND M. TUBERCULOSIS INFECTIONS AMONG WOMEN INMATES T2 - Journal of Biological Systems TI - THE ATTRACTING BASINS AND THE ASSESSMENT OF THE TRANSMISSION COEFFICIENTS FOR HIV AND M. TUBERCULOSIS INFECTIONS AMONG WOMEN INMATES UR - http://www.worldscientific.com/doi/abs/10.1142/S0218339002000457 VL - 10 ID - 2422 ER - TY - JOUR AB - We introduce a spatial stochastic model for the spread of tuberculosis and HIV. We have three parameters: the size of the social cluster for each individual and the infection rates within and outside the social cluster. We show that when the infection rate from outside the cluster is low (this is presumably the case for tuberculosis and HIV) then an epidemic is possible only if the typical social cluster and the within infection rate are large enough. These results may be important in formulating new hypotheses for the transmission of TB and HIV. AD - Department of Mathematics, University of Colorado, Colorado Springs, Colorado 80933-7150, USA. schinazi@math.uccs.edu AN - 11969388 AU - Schinazi, R. B. DA - Mar DO - 10.1006/tpbi.2001.1567 [doi] S0040580901915679 [pii] DP - Nlm ET - 04/24 KW - Cluster Analysis Disease Outbreaks HIV Infections/epidemiology/transmission Humans Models, Statistical Population Density Risk Factors Social Support Stochastic Processes Tuberculosis/ epidemiology/ transmission LA - eng N1 - Schinazi, Rinaldo B United States Theoretical population biology Theor Popul Biol. 2002 Mar;61(2):163-9. PY - 2002 RN - fulltext fulltext_1208 SN - 0040-5809 (Print) 0040-5809 (Linking) SP - 163-9 ST - On the role of social clusters in the transmission of infectious diseases T2 - Theor Popul Biol TI - On the role of social clusters in the transmission of infectious diseases UR - http://ac.els-cdn.com/S0040580901915679/1-s2.0-S0040580901915679-main.pdf?_tid=e2b0ecad40d9f15e4534b3e5d0a67fcd&acdnat=1345013207_d1cc27591f1ef54a2bede8b9d0d62360 VL - 61 ID - 2423 ER - TY - JOUR AB - Models that incorporate local and individual interactions are introduced in the context of the transmission dynamics of tuberculosis (TB). The multi-level contact structure implicitly assumes that individuals are at risk of infection from close contacts in generalized household (clusters) as well as from casual (random) contacts in the general population. Epidemiological time scales are used to reduce the dimensionality of the model and singular perturbation methods are used to corroborate the results of time-scale approximations. The concept and impact of optimal average cluster or generalized household size on TB dynamics is discussed. We also discuss the potential impact of our results on the spread of TB. AD - Department of Biometrics, Mathematical and Theoretical Biology Institute, Cornell University, 432 Warren Hall, Ithaca, NY 14853-7801, USA. AN - 12387923 AU - Song, B. AU - Castillo-Chavez, C. AU - Aparicio, J. P. DA - Nov-Dec DO - S0025556402001128 [pii] DP - Nlm ET - 10/22 KW - Cluster Analysis Contact Tracing Humans Models, Biological Numerical Analysis, Computer-Assisted Time Factors Tuberculosis/epidemiology/ transmission LA - eng N1 - Song, Baojun Castillo-Chavez, Carlos Aparicio, Juan Pablo Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. United States Mathematical biosciences Math Biosci. 2002 Nov-Dec;180:187-205. PY - 2002 RN - fulltext fulltext_1208 SN - 0025-5564 (Print) 0025-5564 (Linking) SP - 187-205 ST - Tuberculosis models with fast and slow dynamics: the role of close and casual contacts T2 - Math Biosci TI - Tuberculosis models with fast and slow dynamics: the role of close and casual contacts UR - http://ac.els-cdn.com/S0025556402001128/1-s2.0-S0025556402001128-main.pdf?_tid=ff43b778ac75d49e2ef08bce209549ec&acdnat=1345013627_f0917b7a8507859196d4207b8f56129c VL - 180 ID - 2424 ER - TY - JOUR AB - Mathematical models for Tuberculosis with linear and logistic growth rates are considered. The global dynamic structure for the logistic recruitment model is analyzed with the help of a strong version of the Poincare-Bendixson Theorem. The nature of the global dynamics of the same model with a linear recruitment rate is established with the use of explicit threshold quantities controlling the absolute and relative spread of the disease and the likelihood of extinction or persistence of the total population. The classification of planar quadratic systems helps rule out the existence of closed orbits (limit cycles). AD - Cornell Univ, Dept Biometr, Ithaca, NY 14853 USA AN - WOS:000176237600016 AU - Song, B. J. AU - Castillo-Chavez, C. AU - Aparicio, J. P. J2 - Ima V Math KW - tuberculosis global stability monotone systems density-dependent recruitment rates autonomous differential-equations growing-populations hiv aids transmission reinfection infections diseases epidemic LA - English N1 - Bu52j Times Cited:7 Cited References Count:33 Ima Volumes in Mathematics and Its Applications PY - 2002 SP - 275-294 ST - Global dynamics of Tuberculosis models with density dependent demography T2 - Mathematical Approaches for Emerging and Reemerging Infectious Diseases: Models, Methods, and Theory TI - Global dynamics of Tuberculosis models with density dependent demography UR - ://WOS:000176237600016 VL - 126 ID - 4833 ER - TY - JOUR AB - OBJECTIVE: To estimate the cost-effectiveness of directly observed treatment compared to conventional therapy in reducing the spread of multidrug-resistant tuberculosis, for an industrialised country (represented by the United States of America) and a developing country (South Africa). METHODS: Monte Carlo analysis using published data on probability, cost and health impact. RESULTS: In both countries, directly observed treatment is the dominant strategy, yielding cost savings and improved health outcomes. Cost savings for directly observed treatment relative to conventional therapy become more significant as more expensive second-line drugs are used in treatments. CONCLUSIONS: The cost-effectiveness of directly observed treatment relative to conventional therapy is demonstrated for both the USA and South Africa. Cost savings are more pronounced (especially for South Africa) as the likelihood of multidrug-resistant tuberculosis increases and more expensive second-line therapies are used. Given that health care resources are more severely constrained in developing countries, the data contained in this study are useful in guiding the design of policies for the effective management of multidrug-resistant tuberculosis in settings with limited resources. AD - Health Economics Group, School of Health Policy and Practice, University of East Anglia, Norwich, United Kingdom. AN - 11769772 AU - Wilton, P. AU - Smith, R. D. AU - Coast, J. AU - Millar, M. AU - Karcher, A. DA - Dec DP - Nlm ET - 01/05 J2 - The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease KW - Antitubercular Agents/economics/ therapeutic use Cost-Benefit Analysis Decision Trees Directly Observed Therapy/ economics Evaluation Studies as Topic Humans Monte Carlo Method South Africa Treatment Outcome Tuberculosis, Multidrug-Resistant/ drug therapy/ economics United States L1 - internal-pdf://1566446810/s10.pdf LA - eng N1 - Wilton, P Smith, R D Coast, J Millar, M Karcher, A Comparative Study France Int J Tuberc Lung Dis. 2001 Dec;5(12):1137-42. PY - 2002 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1027-3719 (Print) 1027-3719 (Linking) SP - 1137-42 ST - Directly observed treatment for multidrug-resistant tuberculosis: an economic evaluation in the United States of America and South Africa T2 - Int J Tuberc Lung Dis TI - Directly observed treatment for multidrug-resistant tuberculosis: an economic evaluation in the United States of America and South Africa VL - 5 ID - 2412 ER - TY - JOUR AB - OBJECTIVE: To determine whether elimination of tuberculosis in the Dutch population can be achieved by the year 2030, taking into account the impact of immigration. METHODS: The incidence of tuberculosis (all forms) in the period 1970 to 2030 was estimated using a life-table model for the Dutch population without the impact of immigration. The influence of immigration on tuberculosis incidence among the Dutch was modelled using four immigrant scenarios, distinguished by the assumed contact rate between immigrants and the Dutch population, and by different projections (middle, upper) of the future size of the immigrant population in The Netherlands. RESULTS: The incidence of smear-positive tuberculosis among the Dutch is projected to be 1.4 per million in the scenario without the influence of immigrant cases, and ranging from 3.8 to 11.8 per million in the four immigrant scenarios. In all immigrant scenarios, the prevalence of tuberculosis infection will continue to decline and be less than 1% by the year 2030. At least 60% of Dutch tuberculosis cases in the year 2030 are expected to be the result of transmission from a foreign source case. CONCLUSION: Using a prevalence of tuberculosis infection of less than 1% as the elimination criterion, tuberculosis will probably be eliminated from the indigenous Dutch population by 2030. However, the incidence of smear-positive tuberculosis is expected to remain higher than 1 per million, and the majority of new tuberculosis cases among the Dutch may be attributable to recent infection from a foreign source case. AD - Pallas, Health Research and Consultancy, Rotterdam, The Netherlands. AN - 11931411 AU - Wolleswinkel-van, B. J. AU - Nagelkerke, N. J. AU - Broekmans, J. F. AU - Borgdorff, M. W. DA - Feb DP - Nlm ET - 04/05 KW - Adolescent Adult Age Distribution Aged Child Emigration and Immigration/ statistics & numerical data Female Humans Male Middle Aged Models, Statistical Netherlands/epidemiology Prevalence Risk Factors Sex Distribution Tuberculosis, Pulmonary/ epidemiology/prevention & control LA - eng N1 - Wolleswinkel-van, den Bosch J H Nagelkerke, N J D Broekmans, J F Borgdorff, M W France The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease Int J Tuberc Lung Dis. 2002 Feb;6(2):130-6. PY - 2002 RN - fulltext fulltext_1208 SN - 1027-3719 (Print) 1027-3719 (Linking) SP - 130-6 ST - The impact of immigration on the elimination of tuberculosis in The Netherlands: a model based approach T2 - Int J Tuberc Lung Dis TI - The impact of immigration on the elimination of tuberculosis in The Netherlands: a model based approach VL - 6 ID - 2425 ER - TY - JOUR AB - The comparative-genomic sequencing of two Mycobacterium tuberculosis strains enabled us to identify single nucleotide polymorphism (SNP) markers for studies of evolution, pathogenesis, and epidemiology in clinical M. tuberculosis. Phylogenetic analysis using these "comparative-genome markers" (CGMs) produced a highly unusual phylogeny with a complete absence of secondary branches. To investigate CGM-based phylogenies, we devised computer models to simulate sequence evolution and calculate new phylogenies based on an SNP format. We found that CGMs represent a distinct class of phylogenetic markers that depend critically on the genetic distances between compared "reference strains." Properly distanced reference strains generate CGMs that accurately depict evolutionary relationships, distorted only by branch collapse. Improperly distanced reference strains generate CGMs that distort and reroot outgroups. Applying this understanding to the CGM-based phylogeny of M. tuberculosis, we found evidence to suggest that this species is highly clonal without detectable lateral gene exchange. We noted indications of evolutionary bottlenecks, including one at the level of the PHRI "C" strain previously associated with particular virulence characteristics. Our evidence also suggests that loss of IS6110 to fewer than seven elements per genome is uncommon. Finally, we present population-based evidence that KasA, an important component of mycolic acid biosynthesis, develops G312S polymorphisms under selective pressure. AD - Department of Medicine, Center for Emerging Pathogens, New Jersey Medical School, Newark, New Jersey 07103, USA. allandda@umdnj.edu AN - 12754238 AU - Alland, D. AU - Whittam, T. S. AU - Murray, M. B. AU - Cave, M. D. AU - Hazbon, M. H. AU - Dix, K. AU - Kokoris, M. AU - Duesterhoeft, A. AU - Eisen, J. A. AU - Fraser, C. M. AU - Fleischmann, R. D. DA - Jun DP - Nlm ET - 05/20 KW - Bacterial Proteins/genetics/metabolism Computational Biology Computer Simulation DNA Transposable Elements Evolution, Molecular Genome, Bacterial Humans Mycobacterium tuberculosis/ genetics/ pathogenicity Phylogeny Polymorphism, Genetic Polymorphism, Single Nucleotide LA - eng N1 - Alland, David Whittam, Thomas S Murray, Megan B Cave, M Donald Hazbon, Manzour H Dix, Kim Kokoris, Mark Duesterhoeft, Andreas Eisen, Jonathan A Fraser, Claire M Fleischmann, Robert D AI40125/AI/NIAID NIH HHS/United States AI46669/AI/NIAID NIH HHS/United States AI49352/AI/NIAID NIH HHS/United States Comparative Study Research Support, U.S. Gov't, P.H.S. United States Journal of bacteriology J Bacteriol. 2003 Jun;185(11):3392-9. PY - 2003 RN - fulltext fulltext_1208 SN - 0021-9193 (Print) 0021-9193 (Linking) SP - 3392-9 ST - Modeling bacterial evolution with comparative-genome-based marker systems: application to Mycobacterium tuberculosis evolution and pathogenesis T2 - J Bacteriol TI - Modeling bacterial evolution with comparative-genome-based marker systems: application to Mycobacterium tuberculosis evolution and pathogenesis UR - http://jb.asm.org/content/185/11/3392.full.pdf VL - 185 ID - 2426 ER - TY - JOUR AB - Tuberculosis (TB) is a disease that is closely associated with poverty, with transmission occurring in situations where infected persons are in close contact with others in confined spaces. While it is well recognised that overcrowding increases the risk of transmission, this increased risk has not been quantified and the relationship between overcrowding and duration of exposure is not well understood. This paper analyses three epidemiological models that have been used to predict the transmission of airborne disease in confined spaces: the Mass Action model, Riley, Murphy and Riley's model and Gammaitoni and Nucci's model. A study is presented to demonstrate the range of applicability of each model and show how they can be applied to the transmission of both TB and diseases with short incubation periods such as measles. Gammiatoni and Nucci's generalised formulation is shown to be the most suitable for modelling airborne transmission in ventilated spaces, and it is subsequently used in a parametric study to evaluate the effect of physical and environmental factors on the rate of disease transmission. The paper also presents reported quanta production data for several TB outbreaks and demonstrates that the greatest risk of TB infection is during clinical procedures that produce large quantities of aerosol, such as bronchoscopy or intubation. AD - Aerobiological Research Group, School of Civil Engineering, University of Leeds, Leeds, United Kingdom. c.b.beggs@leeds.ac.uk AN - 14598959 AU - Beggs, C. B. AU - Noakes, C. J. AU - Sleigh, P. A. AU - Fletcher, L. A. AU - Siddiqi, K. DA - Nov DP - Nlm ET - 11/06 KW - Disease Transmission, Infectious/ statistics & numerical data Environmental Exposure Humans Models, Statistical Population Density Risk Assessment Risk Factors Time Factors Tuberculosis, Pulmonary/ epidemiology/ transmission LA - eng N1 - Beggs, C B Noakes, C J Sleigh, P A Fletcher, L A Siddiqi, K Review France The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease Int J Tuberc Lung Dis. 2003 Nov;7(11):1015-26. PY - 2003 RN - fulltext fulltext_1208 SN - 1027-3719 (Print) 1027-3719 (Linking) SP - 1015-26 ST - The transmission of tuberculosis in confined spaces: an analytical review of alternative epidemiological models T2 - Int J Tuberc Lung Dis TI - The transmission of tuberculosis in confined spaces: an analytical review of alternative epidemiological models VL - 7 ID - 2427 ER - TY - JOUR AB - Tuberculosis (TB) is a major public health problem in complex emergencies. Humanitarian agencies usually postpone the decision to offer TB treatment and opportunities to treat TB patients are often missed. This paper looks at the problem of tuberculosis treatment in these emergencies and questions whether treatment guidelines could be more flexible than international recommendations. A mathematical model is used to calculate the risks and benefits of different treatment scenarios with increasing default rates. Model outcomes are compared to a situation without treatment. An economic analysis further discusses the findings in a trade-off between the extra costs of treating relapses and failures and the savings in future treatment costs. In complex emergencies, if a TB programme could offer 4-month treatment for 75% of its patients, it could still be considered beneficial in terms of public health. In addition, the proportion of patients following at least 4 months of treatment can be used as an indicator to help evaluate the public health harm and benefit of the TB programme. AN - 15173 AU - Biot, M. AU - Chandramohan, D. AU - Porter, J. D. H. KW - adherence displaced persons drug resistance emergency relief epidemiology immigrants migration models treatment tuberculosis L1 - internal-pdf://0471661017/Biot%2520Math%2520Model.pdf N1 - IN FILE TB Transmission, pathogenesis, and epidemiology Tuberculosis Descript epi: morbidity Displaced persons PY - 2003 RN - fulltext fulltext_1208 SP - 211-218 ST - Tuberculosis treatment in complex emergencies: are risks outweighing benefits? T2 - Trop.Med.Intern.Health TI - Tuberculosis treatment in complex emergencies: are risks outweighing benefits? UR - file://C:\literature_pdf\rm15173.pdf VL - 8 ID - 2428 ER - TY - JOUR AB - Traditional cost-effectiveness analysis (CEA) assumes that program costs and benefits scale linearly with investment-an unrealistic assumption for epidemic control programs. This paper combines epidemic modeling with optimization techniques to determine the optimal allocation of a limited resource for epidemic control among multiple noninteracting populations. We show that the optimal resource allocation depends on many factors including the size of each population, the state of the epidemic in each population before resources are allocated (e.g. infection prevalence and incidence), the length of the time horizon, and prevention program characteristics. We establish conditions that characterize the optimal solution in certain cases. AD - Department of Management Science and Engineering, Stanford University, Terman Building, Stanford, CA 94305, USA. brandeau@stanford.edu AN - 12842316 AU - Brandeau, M. L. AU - Zaric, G. S. AU - Richter, A. DA - Jul KW - Communicable Disease Control/*economics Cost-Benefit Analysis Disease Outbreaks/economics/*prevention & control Health Services Needs and Demand/economics/statistics & numerical data Human Models, Econometric Prevalence Quality-Adjusted Life Years Resource Allocation/economics/*methods/statistics & numerical data Support, Non-U.S. Gov't Support, U.S. Gov't, Non-P.H.S. Support, U.S. Gov't, P.H.S. World Health N1 - 0167-6296 Journal Article PY - 2003 RN - fulltext fulltext_1208 SP - 575-98 ST - Resource allocation for control of infectious diseases in multiple independent populations: beyond cost-effectiveness analysis T2 - Journal of Health Economics TI - Resource allocation for control of infectious diseases in multiple independent populations: beyond cost-effectiveness analysis UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=12842316 VL - 22 ID - 2429 ER - TY - JOUR AB - Mycobacterium tuberculosis remains a leading infectious cause of morbidity and mortality. While antibiotic resistance is cited as a potential threat to efforts aimed at controlling the spread of this pathogen, it is not clear how drug resistance affects disease dynamics. The effect of mutational events that lead to antibiotic-resistant phenotypes may or may not have a predictable effect on the fitness of drug-resistant tuberculosis strains. Here, we review the literature on laboratory studies of the fitness of drug-resistant tuberculosis, we examine the evidence from cluster studies, and we consider the effect of drug resistance on disease dynamics in mathematical models. On the basis of these diverse lines of evidence, we conclude that the fitness estimates of drug-resistant M tuberculosis are quite heterogeneous and that this variation may preclude our ability to predict future trends of this pathogen. AU - Cohen, T. AU - Sommers, B. AU - Murray, M. IS - 1 KW - *Mycobacterium tuberculosis/drug effects/genetics/ Antitubercular Agents/*pharmacology Cluster Analysis Drug Resistance, Multiple, Bacterial Humans Molecular Epidemiology Prevalence Tuberculosis/*epidemiology L1 - file:///C:/Users/James/AppData/Local/Mendeley Ltd/Mendeley Desktop/Downloaded/Cohen-2003-The effect of drug resistance on th.pdf N1 - Cohen, Ted Sommers, Ben Murray, Megan eng K08 A1 01930-01/PHS HHS/ K08 AI055985-01A1/AI/NIAID NIH HHS/ R01 A10 46669-02/PHS HHS/ T32 AI07433/AI/NIAID NIH HHS/ Research Support, U.S. Gov't, P.H.S. Review 2002/12/31 04:00 Lancet Infect Dis. 2003 Jan;3(1):13-21. PY - 2003 SN - 1473-3099 (Print) 1473-3099 (Linking) SP - 13-21 ST - The effect of drug resistance on the fitness of Mycobacterium tuberculosis T2 - Lancet Infect Dis TI - The effect of drug resistance on the fitness of Mycobacterium tuberculosis UR - http://www.ncbi.nlm.nih.gov/pubmed/12505028 http://ac.els-cdn.com.ezp.lib.unimelb.edu.au/S1473309903004833/1-s2.0-S1473309903004833-main.pdf?_tid=4d149104-5c99-11e4-9286-00000aab0f02&acdnat=1414277602_43658d241c5d537be879b37fa047c33c VL - 3 ID - 3429 ER - TY - JOUR AB - BACKGROUND: The increasing global burden of tuberculosis (TB) is linked to human immunodeficiency virus (HIV) infection. METHODS: We reviewed data from notifications of TB cases, cohort treatment outcomes, surveys of Mycobacterium tuberculosis infection, and HIV prevalence in patients with TB and other subgroups. Information was collated from published literature and databases held by the World Health Organization (WHO), the Joint United Nations Programme on HIV/Acquired Immunodeficiency Syndrome (UNAIDS), the US Census Bureau, and the US Centers for Disease Control and Prevention. RESULTS: There were an estimated 8.3 million (5th-95th centiles, 7.3-9.2 million) new TB cases in 2000 (137/100,000 population; range, 121/100,000-151/100,000). Tuberculosis incidence rates were highest in the WHO African Region (290/100,000 per year; range, 265/100,000-331/100,000), as was the annual rate of increase in the number of cases (6%). Nine percent (7%-12%) of all new TB cases in adults (aged 15-49 years) were attributable to HIV infection, but the proportion was much greater in the WHO African Region (31%) and some industrialized countries, notably the United States (26%). There were an estimated 1.8 million (5th-95th centiles, 1.6-2.2 million) deaths from TB, of which 12% (226 000) were attributable to HIV. Tuberculosis was the cause of 11% of all adult AIDS deaths. The prevalence of M tuberculosis-HIV coinfection in adults was 0.36% (11 million people). Coinfection prevalence rates equaled or exceeded 5% in 8 African countries. In South Africa alone there were 2 million coinfected adults. CONCLUSIONS: The HIV pandemic presents a massive challenge to global TB control. The prevention of HIV and TB, the extension of WHO DOTS programs, and a focused effort to control HIV-related TB in areas of high HIV prevalence are matters of great urgency. AD - Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, England, UK. AN - 12742798 AU - Corbett, E. L. AU - Watt, C. J. AU - Walker, N. AU - Maher, D. AU - Williams, B. G. AU - Raviglione, M. C. AU - Dye, C. DA - May 12 KW - AIDS-Related Opportunistic Infections/*epidemiology/prevention & control HIV Seronegativity HIV Seropositivity/*complications/epidemiology Humans Incidence Prevalence Registries Tuberculosis/*epidemiology/mortality/prevention & control/transmission Tuberculosis, Pulmonary/epidemiology World Health N1 - 0003-9926 (Print) Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Review PY - 2003 SP - 1009-21 ST - The growing burden of tuberculosis: global trends and interactions with the HIV epidemic T2 - Arch Intern Med TI - The growing burden of tuberculosis: global trends and interactions with the HIV epidemic UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=12742798http://archinte.jamanetwork.com/data/Journals/INTEMED/5439/ira20017.pdf VL - 163 ID - 2430 ER - TY - JOUR AB - OBJECTIVE: To compare the benefits of tuberculosis (TB) treatment with TB and HIV prevention for the control of TB in regions with high HIV prevalence. DESIGN AND METHODS: A compartmental difference equation model of TB and HIV has been developed and fitted to time series and other published data using Bayesian methods. The model is used to compare the effectiveness of TB chemotherapy with three strategies for prevention: highly active antiretroviral therapy (HAART), the treatment of latent TB infection (TLTI) and the reduction of HIV transmission. RESULTS: Even where the prevalence of HIV infection is high, finding and curing active TB is the most effective way to minimize the number of TB cases and deaths over the next 10 years. HAART can be as effective, but only with very high levels of coverage and compliance. TLTI is comparatively ineffective over all time scales. Reducing HIV incidence is relatively ineffective in preventing TB and TB deaths over 10 years but is much more effective over 20 years. CONCLUSIONS: In countries where the spread of HIV has led to a substantial increase in the incidence of TB, TB control programmes should maintain a strong emphasis on the treatment of active TB. To ensure effective control of TB in the longer term, methods of TB prevention should be carried out in addition to, but not as a substitute for, treating active cases. AD - Faculty of Mathematical Studies, University of Southampton, Southampton, UK. AN - 14600522 AU - Currie, C. S. AU - Williams, B. G. AU - Cheng, R. C. AU - Dye, C. DA - Nov 21 DO - 10.1097/01.aids.0000096903.73209.ac [doi] DP - Nlm ET - 11/06 KW - AIDS-Related Opportunistic Infections/ epidemiology/prevention & control Antiretroviral Therapy, Highly Active Bayes Theorem Developing Countries Disease Outbreaks/ prevention & control Humans Incidence Kenya/epidemiology Models, Statistical Prevalence South Africa/epidemiology Time Factors Tuberculosis/ epidemiology/prevention & control Uganda/epidemiology LA - eng N1 - Currie, Christine S M Williams, Brian G Cheng, Russell C H Dye, Christopher England AIDS (London, England) AIDS. 2003 Nov 21;17(17):2501-8. PY - 2003 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 0269-9370 (Print) 0269-9370 (Linking) SP - 2501-8 ST - Tuberculosis epidemics driven by HIV: is prevention better than cure? T2 - AIDS TI - Tuberculosis epidemics driven by HIV: is prevention better than cure? UR - http://graphics.tx.ovid.com/ovftpdfs/FPDDNCDCLFEDDD00/fs046/ovft/live/gv023/00002030/00002030-200311210-00013.pdf VL - 17 ID - 2431 ER - TY - JOUR AB - A decision analysis was conducted to evaluate the cost-effectiveness of programs in which the Amplified Mycobacterium Tuberculosis Direct test (MTD) (Gen-Probe) is used to rapidly exclude Mycobacterium tuberculosis complex as a cause of disease in smear-positive respiratory specimens. MTD sensitivity, specificity, and probability of inhibition for smear-positive specimens were estimated from literature reports. Costs and laboratory performance characteristics were determined from review of records and practices at an urban hospital in the mid-Atlantic United States. In the base case, 31.4% of smear-positive specimens were assumed to be culture positive for M. tuberculosis. Under these conditions, the marginal cost of the MTD testing program was estimated as $338 per smear-positive patient, or $494 per early exclusion of tuberculosis based on negative MTD results. By comparison, the cost of respiratory isolation ($27.77/day) and drugs ($5.66/day) averted by MTD testing was estimated at $201 per early tuberculosis exclusion. MTD testing was therefore not cost-effective in this scenario. Sensitivity analysis revealed that cost-effectiveness estimates are sensitive to the number of smear-positive specimens processed annually, the relative prevalence of M. tuberculosis in smear-positive specimens, and the marginal daily cost of respiratory isolation. A decision tool is therefore presented for assessing the cost-effectiveness of MTD under various combinations of those three variables. While routine MTD testing of smear-positive specimens is not expected to be cost-saving for most individual hospitals, centralized reference laboratories may be able to implement MTD in a cost-effective manner across a wide range of situations. AD - Johns Hopkins Bloomberg School of Public Health. Johns Hopkins Hospital. Johns Hopkins University School of Medicine, Baltimore, Maryland. AN - 12624014 AU - Dowdy, D. W. AU - Maters, A. AU - Parrish, N. AU - Beyrer, C. AU - Dorman, S. E. DA - Mar N1 - 22511020 0095-1137 Journal Article PY - 2003 RN - fulltext fulltext_1208 SP - 948-953 ST - Cost-effectiveness analysis of the gen-probe amplified mycobacterium tuberculosis direct test as used routinely on smear-positive respiratory specimens T2 - Journal of clinical microbiology TI - Cost-effectiveness analysis of the gen-probe amplified mycobacterium tuberculosis direct test as used routinely on smear-positive respiratory specimens UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=12624014file://C:\literature_pdf\rm11132.pdf VL - 41 ID - 2432 ER - TY - JOUR AB - SETTING: Mycobacterium bovis bacille Calmette-Guerin (BCG) is provided to all infants born in Finland. OBJECTIVE: To analyze the cost-effectiveness of universal versus selective BCG immunization. DESIGN: A Markov model was developed to simulate rates of tuberculosis (TB) and non-tuberculous mycobacterial disease (NTM), and to examine the cost-effectiveness in terms of cost per case averted of three different strategies: universal BCG, selective BCG (10% of infants at higher TB risk than other infants) or no BCG immunization. RESULTS: In a cohort of 60,000 infants over 15 years, the model predicts five cases each of TB and NTM disease with universal immunization, 8-21 TB and 31 NTM cases with various strategies of selective immunization, and 25 TB and 34 NTM cases with no BCG immunization. BCG side-effects are predicted in 5, 0.5 and 0 infants, respectively. The cost per case averted for immunization strategies ranges from a cost of 38,311 US dollars to a savings of 323 dollars as selective immunization becomes more efficient at targeting infants at highest risk of TB. CONCLUSIONS: In a country with a low incidence of pediatric tuberculosis, selective BCG immunization is a more cost-effective strategy than universal BCG immunization for the prevention of tuberculosis, but results in an increase in NTM cases. AD - Infectious Disease Section, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire 03756, USA. AN - 12701831 AU - Hersh, A. L. AU - Tala-Heikkila, M. AU - Tala, E. AU - Tosteson, A. N. AU - Fordham von Reyn, C. DA - Jan KW - BCG Vaccine/administration & dosage/*economics Cohort Studies Cost of Illness Cost-Benefit Analysis Finland/epidemiology Humans Immunization Programs/*economics/organization & administration Incidence Infant Markov Chains Mass Immunization/economics *Patient Selection Tuberculosis/epidemiology/*prevention & control LA - eng N1 - Comparative Study Journal Article France the official journal of the International Union against Tuberculosis and Lung Disease PY - 2003 RN - fulltext fulltext_1208 SN - 1027-3719 (Print) SP - 22-29 ST - A cost-effectiveness analysis of universal versus selective immunization with Mycobacterium bovis bacille Calmette-Guerin in Finland T2 - International Journal of Tuberculosis and Lung Disease TI - A cost-effectiveness analysis of universal versus selective immunization with Mycobacterium bovis bacille Calmette-Guerin in Finland UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=12701831 VL - 7 ID - 2433 ER - TY - JOUR AB - Recent data indicate that 10- to 14-mm Mycobacterium tuberculosis purified protein derivative (PPD) reactions are often due to prior infections with nontuberculous mycobacteria. Therefore, use of a 10-mm cutpoint to define latent tuberculosis infection (LTBI) results in false-positive diagnoses and unnecessary treatment for LTBI. A second skin test, Mycobacterium avium sensitin (MAS), has been shown to accurately identify false-positive PPD results.To compare the costs and accuracy of a single skin-test strategy (SST) with PPD alone with a dual skin-test strategy (DST) where 10- to 14-mm PPD results are also tested with MAS.A decision analytic model was developed to evaluate the two strategies. The model accounted for the costs of skin testing, the costs of LTBI treatment, the costs of undetected LTBI, and the sensitivity and specificity of each strategy.We estimated that DST saved $3 per subject tested compared to SST. Savings were due to a reduction in false-positive PPD results and consequent reduction in unnecessary treatment for LTBI of >60%. The DST strategy was associated with a minimal increase in undetected LTBI (6% vs 7%). Results were stable for a broad range of parameter values.DST is a promising approach to improving the specificity of LTBI testing when a 10-mm PPD cutpoint is used and would reduce costs and unnecessary drug treatment. AD - Stanford Center for Research in Disease Prevention (Hersh), Stanford University School of Medicine, Palo Alto, California, USA AN - 12657344 AU - Hersh, A. L. AU - Tosteson, A. N. AU - von Reyn, C. F. DA - Apr N1 - 22543442 0749-3797 Journal Article PY - 2003 RN - fulltext fulltext_1208 SP - 254-9 ST - Dual skin testing for latent tuberculosis infection. A decision analysis T2 - American Journal of Preventive Medicine TI - Dual skin testing for latent tuberculosis infection. A decision analysis UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=12657344 VL - 24 ID - 2434 ER - TY - JOUR AB - We consider a model for a disease with a progressing and a quiescent exposed class and variable susceptibility to super-infection. The model exhibits backward bifurcations under certain conditions, which allow for both stable and unstable endemic states when the basic reproduction number is smaller than one. AD - Department of Mathematics, Polytechnic University, Brooklyn, NY 11201, USA. mayam@duke.poly.edu AN - 12750833 AU - Martcheva, M. AU - Thieme, H. R. DA - May DO - 10.1007/s00285-002-0181-7 [doi] DP - Nlm ET - 05/17 KW - HIV Infections Humans Malaria Models, Biological Schistosomiasis Superinfection/ microbiology/ parasitology Tuberculosis LA - eng N1 - Martcheva, Maia Thieme, Horst R Research Support, U.S. Gov't, Non-P.H.S. Germany Journal of mathematical biology J Math Biol. 2003 May;46(5):385-424. PY - 2003 RN - fulltext fulltext_1208 SN - 0303-6812 (Print) 0303-6812 (Linking) SP - 385-424 ST - Progression age enhanced backward bifurcation in an epidemic model with super-infection T2 - J Math Biol TI - Progression age enhanced backward bifurcation in an epidemic model with super-infection UR - http://www.springerlink.com/content/flqdyuk1j4qqpr3m/ VL - 46 ID - 2435 ER - TY - JOUR AB - Global eradication of tuberculosis (TB) is an international agenda. Thus understanding effects of treatment of TB in different settings is crucial. In previous work, we introduced the framework for a mathematical model of epidemic TB in demographically distinct, heterogeneous populations. Simulations showed the importance of genetic susceptibility in determining endemic prevalence levels. In the work presented here, we include treatment and investigate different strategies for treatment of latent and active TB disease in heterogeneous populations. We illustrate how the presence of a genetically susceptible subpopulation dramatically alters effects of treatment in the same way a core population does in the setting of sexually transmitted diseases. In addition, we evaluate treatment strategies that focus specifically on this subpopulation, and our results indicate that genetically susceptible subpopulations should be accounted for when designing treatment strategies to achieve the greatest reduction in disease prevalence. AD - Department of Microbiology and Immunology, The University of Michigan Medical School, University of Michigan at Ann Arbor, 6730 Medical Science II, MC 0620, Ann Arbor, MI 48109-0620, USA. AN - 12875819 AU - Murphy, B. M. AU - Singer, B. H. AU - Kirschner, D. DA - Aug 21 DO - S0022519303000389 [pii] DP - Nlm ET - 07/24 KW - Demography Disease Outbreaks Disease Progression Genetic Predisposition to Disease Humans Models, Statistical Mycobacterium tuberculosis Recurrence/prevention & control Tuberculosis/ drug therapy/ epidemiology/genetics World Health LA - eng N1 - Murphy, Brian M Singer, Benjamin H Kirschner, Denise 5 T32 AI07528/AI/NIAID NIH HHS/United States R01 HL62119/HL/NHLBI NIH HHS/United States Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. England Journal of theoretical biology J Theor Biol. 2003 Aug 21;223(4):391-404. PY - 2003 RN - fulltext fulltext_1208 SN - 0022-5193 (Print) 0022-5193 (Linking) SP - 391-404 ST - On treatment of tuberculosis in heterogeneous populations T2 - J Theor Biol TI - On treatment of tuberculosis in heterogeneous populations UR - http://ac.els-cdn.com/S0022519303000389/1-s2.0-S0022519303000389-main.pdf?_tid=5f5a5b849f1d2b02fed9e32e89154e59&acdnat=1345014079_403666f84fb9ad7f79738dcc5575ac43 VL - 223 ID - 2436 ER - TY - JOUR AB - A mathematical model is presented to simulate the interaction between Human Immunodeficiency Virus (HIV) and Mycobacterium tuberculosis (MTB) infections in a closed environment. The dynamics is formulated through a compartmental system of non-linear ordinary differential equations. The stability of the trivial equilibrium point or absence of infections and the endemic basins are analyzed based on the threshold values for the HIV and MTB transmission coefficients. In order to deal with the estimation of the transmission coefficients of HIV and MTB infections we consider the incarcerated individuals in the Female Penitentiary of S?o Paulo State, Brazil. AU - Raimundo, Silvia Martorano AU - Engel, Alejandro B. AU - Yang, Hyun Mo AU - Bassanezi, Rodney Carlos DA - 2003/04/01 DO - 10.1080/02329290290027175 PY - 2003 RN - fulltext fulltext_1208 SN - 0232-9298 SP - 423-442 ST - An Approach to Estimating the Transmission Coefficients for AIDS and for Tuberculosis Using Mathematical Models T2 - Systems Analysis Modelling Simulation TI - An Approach to Estimating the Transmission Coefficients for AIDS and for Tuberculosis Using Mathematical Models UR - http://dx.doi.org/10.1080/02329290290027175http://www.tandfonline.com/doi/abs/10.1080/02329290290027175 VL - 43 Y2 - 2012/08/10 ID - 2437 ER - TY - JOUR AN - 10553 AU - Rust, P. KW - epidemiology infection mixture analysis models prevalence statistics tuberculosis N1 - TB Periodical PY - 2003 RN - fulltext fulltext_1208 SP - 194-197 ST - Standard errors in mixture studies of tuberculous infection prevalence T2 - Int.J.Tuberc.Lung Dis. TI - Standard errors in mixture studies of tuberculous infection prevalence UR - file://C:\literature_pdf\rm10553.pdf VL - 7 ID - 2438 ER - TY - JOUR AB - We introduce a spatial stochastic model for the spread of tuberculosis. After a primary infection, an individual may become sick (and infectious) through an endogenous reinfection or through an exogenous reinfection. We show that even in the absence of endogenous reinfection an epidemic is possible if the exogenous reinfection parameter is high enough. This is in sharp contrast with what happens for a mean field model corresponding to our spatial stochastic model. AD - LATP/CMI, Universite de Provence, 39 rue Joliot Curie, 13453 Marseille Cedex, France. schinazi@cmi.univ-mrs.fr AU - Schinazi, R. B. KW - Disease Outbreaks Disease Transmission, Infectious Humans Models, Statistical Recurrence Tuberculosis/transmission N1 - LR: 20081121; JID: 0376342; ppublish PY - 2003 RN - fulltext fulltext_1208 SN - 0022-5193 begin_of_the_skype_highlighting 0022-5193 end_of_the_skype_highlighting begin_of_the_skype_highlighting 0022-5193 begin_of_the_skype_highlighting 0022-5193 end_of_the_skype_highlighting end_of_the_skype_highlighting; 0022-5193 begin_of_the_skype_highlighting 0022-5193 end_of_the_skype_highlighting begin_of_the_skype_highlighting 0022-5193 begin_of_the_skype_highlighting 0022-5193 end_of_the_skype_highlighting end_of_the_skype_highlighting SP - 59-63 ST - On the role of reinfection in the transmission of infectious diseases T2 - Journal of theoretical biology TI - On the role of reinfection in the transmission of infectious diseases VL - 225 Y2 - Nov 7 ID - 2439 ER - TY - JOUR AB - OBJECTIVE: This study sought to determine the impact of the World Health Organization's directly observed treatment strategy (DOTS) compared with that of DOTS-plus on tuberculosis deaths, mainly in the developing world. DESIGN: Decision analysis with Monte Carlo simulation of a Markov decision tree. DATA SOURCES: People with smear positive pulmonary tuberculosis. DATA ANALYSIS: Analyses modelled different levels of programme effectiveness of DOTS and DOTS-plus, and high (10%) and intermediate (3%) proportions of primary multidrug resistant tuberculosis, while accounting for exogenous reinfection. MAIN OUTCOME MEASURE: The cumulative number of tuberculosis deaths per 100 000 population over 10 years. RESULTS: The model predicted that under DOTS, 276 people would die from tuberculosis (24 multidrug resistant and 252 not multidrug resistant) over 10 years under optimal implementation in an area with 3% primary multidrug resistant tuberculosis. Optimal implementation of DOTS-plus would result in four (1.5%) fewer deaths. If implementation of DOTS-plus were to result in a decrease of just 5% in the effectiveness of DOTS, 16% more people would die with tuberculosis than under DOTS alone. In an area with 10% primary multidrug resistant tuberculosis, 10% fewer deaths would occur under optimal DOTS-plus than under optimal DOTS, but 16% more deaths would occur if implementation of DOTS-plus were to result in a 5% decrease in the effectiveness of DOTS CONCLUSIONS: Under optimal implementation, fewer tuberculosis deaths would occur under DOTS-plus than under DOTS. If, however, implementation of DOTS-plus were associated with even minimal decreases in the effectiveness of treatment, substantially more patients would die than under DOTS. AD - Johns Hopkins University Center for Tuberculosis Research, 424 N Bond Street, Baltimore, MD 21231, USA. tsterls@jhmi.edu AN - 12637401 AU - Sterling, T. R. AU - Lehmann, H. P. AU - Frieden, T. R. DA - Mar 15 L1 - internal-pdf://1225460229/Sterling-2003-Impact of DOTS compared with DOT.pdf N1 - 22523683 1468-5833 Journal Article PY - 2003 RN - fulltext fulltext_1208 SP - 574 ST - Impact of DOTS compared with DOTS-plus on multidrug resistant tuberculosis and tuberculosis deaths: decision analysis T2 - British Medical Journal TI - Impact of DOTS compared with DOTS-plus on multidrug resistant tuberculosis and tuberculosis deaths: decision analysis UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=12637401 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC151519/pdf/574.pdf VL - 326 ID - 2440 ER - TY - JOUR AB - Several recent studies have used proportions of tuberculosis cases sharing identical DNA fingerprint patterns (i.e., isolate clustering) to estimate the extent of disease attributable to recent transmission. Using a model of introduction and transmission of strains with different DNA fingerprint patterns, we show that the properties and interpretation of clustering statistics may differ substantially between settings. For some unindustrialized countries, where the annual risk for infection has changed little over time, 70% to 80% of all age groups may be clustered during a 3-year period, which underestimates the proportion of disease attributable to recent transmission. In contrast, for a typical industrialized setting (the Netherlands), clustering declines with increasing age (from 75% to 15% among young and old patients, respectively) and underestimates the extent of recent transmission only for young patients. We conclude that, in some settings, clustering is an unreliable indicator of the extent of recent transmission. AD - London School of Hygiene & Tropical Medicine, London, England. emilia.vynnycky@lshtm.ac.uk AN - 12603987 AU - Vynnycky, E. AU - Borgdorff, M. W. AU - Van Soolingen, D. AU - Fine, P. E. PY - 2003 RN - fulltext fulltext_1208 SP - 176-83. ST - Annual Mycobacterium tuberculosis Infection Risk and Interpretation of Clustering Statistics T2 - Emerg Infect Dis TI - Annual Mycobacterium tuberculosis Infection Risk and Interpretation of Clustering Statistics UR - http://www.ncbi.nlm.nih.gov/htbin-post/Entrez/query?db=m&form=6&dopt=r&uid=12603987 VL - 9 ID - 2441 ER - TY - JOUR AB - Human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) has dramatically increased the incidence of tuberculosis (TB) in subSaharan Africa, where up to 60% of TB patients are coinfected with HIV and each year 200,000 TB deaths are attributable to HIV coinfection. Now HIV threatens control of TB in Asia, Eastern Europe, and Latin America. Antiretroviral (ARV) drugs can prevent TB by preserving immunity, but cohort analysis shows that early therapy, plus high levels of coverage and compliance, will be needed to avert a significant fraction of TB cases. However, ARV drugs could enhance the treatment of TB, and TB programs provide an important entry point for the treatment of HIV/AIDS. AD - Communicable Diseases, World Health Organization, 1211 Geneva 27, Switzerland. williamsbg@who.int AU - Williams, B. G. AU - Dye, C. DO - 10.1126/science.1086845 KW - Acquired Immunodeficiency Syndrome/complications/drug therapy/immunology/mortality Africa South of the Sahara/epidemiology Anti-HIV Agents/therapeutic use Antitubercular Agents/therapeutic use CD4 Lymphocyte Count Cohort Studies Developing Countries Drug Therapy, Combination Female HIV Infections/complications/drug therapy/immunology/mortality HIV-1 HIV-2 Humans Incidence Male Survival Rate Tuberculosis/complications/drug therapy/epidemiology/prevention & control N1 - LR: 20070319; JID: 0404511; 0 (Anti-HIV Agents); 0 (Antitubercular Agents); 2003/08/14 [aheadofprint]; ppublish PY - 2003 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1095-9203; 0036-8075 SP - 1535-1537 ST - Antiretroviral drugs for tuberculosis control in the era of HIV/AIDS T2 - Science (New York, N.Y.) TI - Antiretroviral drugs for tuberculosis control in the era of HIV/AIDS UR - http://www.sciencemag.org/content/301/5639/1535.full.pdf VL - 301 Y2 - Sep 12 ID - 2442 ER - TY - JOUR AB - OBJECTIVE: To compare the cost-effectiveness of three diagnostic algorithms incorporating a new rapid test, FASTPlaqueTB, with the current National TB Control Programme (NTCP) algorithm for diagnosis of pulmonary tuberculosis in new smear-negative suspects in South Africa. DESIGN: A model of the outcome of patients screened using each diagnostic algorithm was established using published costs and performance data for each component of the algorithm. Direct health care provider costs associated with provision of each diagnostic strategy were determined. Overall performance, total cost, speed and accuracy of diagnosis were estimated for screening 1000 new TB suspects using each algorithm. RESULTS: The use of FASTPlaqueTB and culture algorithms enabled 28% more smear-negative TB patients to be diagnosed overall and was cheaper to implement than the NTCP algorithm (18,312-18,581 US dollars compared with 20,079 dollars). Fewer clinic visits were required to establish a diagnosis, reducing clinic workload and patient costs. FASTPlaqueTB enabled rapid and specific diagnosis of at least 50% of smear-negative TB patients within 2 days. CONCLUSIONS: The use of FASTPlaqueTB can assist in improving existing case detection strategies and may be cost-effectively integrated into the current diagnostic infrastructure, offering patients more rapid and reliable diagnosis whilst reducing the overall cost. AD - Biotec Laboratories Ltd., c/o National Health Laboratory Service, Cape Town, Western Cape, South Africa. alberth@mweb.co.za AN - 15139454 AU - Albert, H. DA - Feb ET - 05/14 J2 - The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease KW - *Algorithms Bacteriological Techniques/*economics Cost-Benefit Analysis Humans Mycobacterium tuberculosis/classification Predictive Value of Tests South Africa Sputum/*microbiology Time Factors Tuberculosis, Pulmonary/*diagnosis LA - eng M3 - Comparative Study N1 - Albert, H France Int J Tuberc Lung Dis. 2004 Feb;8(2):240-7. PY - 2004 SN - 1027-3719 (Print) 1027-3719 (Linking) SP - 240-7 ST - Economic analysis of the diagnosis of smear-negative pulmonary tuberculosis in South Africa: incorporation of a new rapid test, FASTPlaqueTB, into the diagnostic algorithm T2 - Int J Tuberc Lung Dis TI - Economic analysis of the diagnosis of smear-negative pulmonary tuberculosis in South Africa: incorporation of a new rapid test, FASTPlaqueTB, into the diagnostic algorithm UR - http://www.ncbi.nlm.nih.gov/pubmed/15139454 VL - 8 ID - 2443 ER - TY - JOUR AB - 'Hot zones' are areas that have >5% prevalence (or incidence) of multidrug-resistant tuberculosis (MDRTB). We present a new mathematical model (the amplifier model) that tracks the emergence and evolution of multiple (pre-MDR, MDR and post-MDR) strains of drug-resistant Mycobacterium tuberculosis. We reconstruct possible evolutionary trajectories that generated hot zones over the past three decades, and identify the key causal factors. Results are consistent with recently reported World Health Organization (WHO) data. Our analyses yield three important insights. First, paradoxically we found that areas with programs that successfully reduced wild-type pansensitive strains often evolved into hot zones. Second, some hot zones emerged even when MDR strains were substantially less fit (and thus less transmissible) than wild-type pansensitive strains. Third, levels of MDR are driven by case-finding rates, cure rates and amplification probabilities. To effectively control MDRTB in the hot zones, it is essential that the WHO specify a goal for minimizing the amplification probability. AD - Department of Biomathematics and UCLA AIDS Institute, David Geffen School of Medicine at the University of California, Los Angeles, 1100 Glendon Avenue, Penthouse 2, Westwood, California 90024, USA. sblower@mednet.ucla.edu AN - 15378053 AU - Blower, S. M. AU - Chou, T. DA - Oct DO - 10.1038/nm1102 [doi] nm1102 [pii] DP - Nlm ET - 09/21 KW - Biological Evolution Disease Outbreaks Epidemiologic Research Design Geography Humans Incidence Models, Biological Monte Carlo Method Mycobacterium tuberculosis/genetics/ pathogenicity Prevalence Tuberculosis, Multidrug-Resistant/ epidemiology/prevention & control World Health L1 - internal-pdf://2769125462/Blower-2004-Modeling the emergence of the 'hot.pdf LA - eng N1 - Blower, Sally M Chou, Tom R01 AI041935/AI/NIAID NIH HHS/United States Research Support, U.S. Gov't, Non-P.H.S. Research Support, U.S. Gov't, P.H.S. United States Nature medicine Nat Med. 2004 Oct;10(10):1111-6. Epub 2004 Sep 19. PY - 2004 RN - fulltext fulltext_1208 SN - 1078-8956 (Print) 1078-8956 (Linking) SP - 1111-6 ST - Modeling the emergence of the 'hot zones': tuberculosis and the amplification dynamics of drug resistance T2 - Nat Med TI - Modeling the emergence of the 'hot zones': tuberculosis and the amplification dynamics of drug resistance UR - http://www.nature.com/nm/journal/v10/n10/pdf/nm1102.pdf https://www.nature.com/articles/nm1102.pdf VL - 10 ID - 2444 ER - TY - JOUR AB - The reemergence of tuberculosis (TB) from the 1980s to the early 1990s instigated extensive researches on the mechanisms behind the transmission dynamics of TB epidemics. This article provides a detailed review of the work on the dynamics and control of TB. The earliest mathematical models describing the TB dynamics appeared in the 1960s and focused on the prediction and control strategies using simulation approaches. Most recently developed models not only pay attention to simulations but also take care of dynamical analysis using modern knowledge of dynamical systems. Questions addressed by these models mainly concentrate on TB control strategies, optimal vaccination policies, approaches toward the elimination of TB in the U.S.A., TB co-infection with HIV/AIDS, drug-resistant TB, responses of the immune system, impacts of demography, the role of public transportation systems, and the impact of contact patterns. Model formulations involve a variety of mathematical areas, such as ODEs (Ordinary Differential Equations) (both autonomous and non-autonomous systems), PDEs (Partial Differential Equations), system of difference equations, system of integro-differential equations, Markov chain model, and simulation models. AU - Castillo-Chavez, C. AU - Song, B. IS - 2 N1 - Castillo-Chavez, Carlos Song, Baojun eng 2004/09/01 00:00 Math Biosci Eng. 2004 Sep;1(2):361-404. PY - 2004 SN - 1547-1063 (Print) 1547-1063 (Linking) SP - 361-404 ST - Dynamical models of tuberculosis and their applications T2 - Math Biosci Eng TI - Dynamical models of tuberculosis and their applications UR - http://www.ncbi.nlm.nih.gov/pubmed/20369977 VL - 1 ID - 3918 ER - TY - JOUR AB - Background Tuberculosis (TB) notification rates among First Nations people in British Columbia, Canada, are higher than those among non-First Nations people, although rates are declining more rapidly in the First Nations population. The epidemiology of tuberculous infection and disease during the period 1926–2000 in this population was investigated.Methods The trend in the annual risk of infection (ARI) since 1926 was estimated using tuberculous meningitis mortality statistics and skin testing data. Risks of progression from infection to disease were estimated by fitting model predictions of disease incidence to TB notifications, using maximum likelihood methods. Infectious TB notifications were matched with ARI estimates to obtain the number of transmissions per infectious case over time.Results We estimate that the ARI decreased from more than 10% during the prechemotherapy era to less than 0.1% by 2000. The risks of primary, reactivation, and exogenous re-infection disease among adults aged 25–44 years were 22%, 0.1%, and 6%, respectively. The number of transmissions per infectious case decreased from 16 to 2 from the early 1970s to the late 1990s.Conclusions This study shows that the risk of infection among British Columbia First Nations people is decreasing, while the relative contribution of reactivation to disease incidence is increasing. Once infected, First Nations people may have a higher risk of developing disease than other populations. AU - Clark, Michael AU - Vynnycky, Emilia DA - June 1, 2004 DO - 10.1093/ije/dyh001 PY - 2004 RN - fulltext fulltext_1208 SP - 477-484 ST - The use of maximum likelihood methods to estimate the risk of tuberculous infection and disease in a Canadian First Nations population T2 - International Journal of Epidemiology TI - The use of maximum likelihood methods to estimate the risk of tuberculous infection and disease in a Canadian First Nations population UR - http://ije.oxfordjournals.org/content/33/3/477.abstract VL - 33 ID - 2445 ER - TY - JOUR AB - Mathematical models have recently been used to predict the future burden of multidrug-resistant tuberculosis (MDRTB). These models suggest the threat of multidrug resistance to TB control will depend on the relative 'fitness' of MDR strains and imply that if the average fitness of MDR strains is considerably less than that of drug-sensitive strains, the emergence of resistance will not jeopardize the success of tuberculosis control efforts. Multidrug resistance in M. tuberculosis is conferred by the sequential acquisition of a number of different single-locus mutations that have been shown to have heterogeneous phenotypic effects. Here we model the impact of initial fitness estimates on the emergence of MDRTB assuming that the relative fitness of MDR strains is heterogeneous. We find that even when the average relative fitness of MDR strains is low and a well-functioning control program is in place, a small subpopulation of a relatively fit MDR strain may eventually outcompete both the drug-sensitive strains and the less fit MDR strains. These results imply that current epidemiological measures and short-term trends in the burden of MDRTB do not provide evidence that MDRTB strains can be contained in the absence of specific efforts to limit transmission from those with MDR disease. AD - Department of Epidemiology, Harvard School of Public Health, 677 Huntington Avenue, Boston, Massachusetts 02115, USA. AN - 15378056 AU - Cohen, T. AU - Murray, M. DA - Oct DO - 10.1038/nm1110 [doi] nm1110 [pii] DP - Nlm ET - 09/21 KW - Disease Outbreaks Drug Resistance, Multiple, Bacterial/ genetics Humans Models, Biological Mycobacterium tuberculosis/genetics/ pathogenicity Species Specificity Time Factors Tuberculosis, Multidrug-Resistant/ epidemiology/prevention & control/transmission World Health L1 - internal-pdf://4026727844/Cohen-2004-Modeling epidemics of multidrug-res.pdf LA - eng N1 - Cohen, Ted Murray, Megan K08 AI055985-02/AI/NIAID NIH HHS/United States T32 AI007433-10/AI/NIAID NIH HHS/United States United States Nature medicine Nihms94735 Nat Med. 2004 Oct;10(10):1117-21. Epub 2004 Sep 19. PY - 2004 RN - fulltext fulltext_1208 SN - 1078-8956 (Print) 1078-8956 (Linking) SP - 1117-21 ST - Modeling epidemics of multidrug-resistant M. tuberculosis of heterogeneous fitness T2 - Nat Med TI - Modeling epidemics of multidrug-resistant M. tuberculosis of heterogeneous fitness UR - http://www.nature.com/nm/journal/v10/n10/pdf/nm1110.pdf https://www.nature.com/articles/nm1110.pdf VL - 10 ID - 2446 ER - TY - JOUR AB - The immune response to Mycobacterium tuberculosis (Mtb) infection is the formation of multicellular lesions, or granolomas, in the lung of the individual. However, the structure of the granulomas and the spatial distribution of the immune cells within is not well understood. In this paper we develop a mathematical model investigating the early and initial immune response to Mtb. The model consists of coupled reaction-diffusion-advection partial differential equations governing the dynamics of the relevant macrophage and bacteria populations and a bacteria-produced chemokine. Our novel application of mathematical concepts of internal states and internal velocity allows us to begin to study this unique immunological structure. Volume changes resulting from proliferation and death terms generate a velocity field by which all cells are transported within the forming granuloma. We present numerical results for two distinct infection outcomes: controlled and uncontrolled granuloma growth. Using a simplified model we are able to analytically determine conditions under which the bacteria population decreases, representing early clearance of infection, or grows, representing the initial stages of granuloma formation. AD - Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 49109, USA. AN - 14745511 AU - Gammack, D. AU - Doering, C. R. AU - Kirschner, D. E. DA - Feb DO - 10.1007/s00285-003-0232-8 [doi] DP - Nlm ET - 01/28 KW - Algorithms Cell Count Cell Death/immunology Cell Movement/immunology Chemokines/immunology Chemotaxis, Leukocyte/immunology Granuloma/immunology/microbiology/pathology Humans Immunity, Innate/immunology Macrophages/cytology/ immunology/microbiology Models, Immunological Mycobacterium tuberculosis/cytology/growth & development/immunology Phagocytosis/immunology Tuberculosis/ immunology/microbiology LA - eng N1 - Gammack, D Doering, C R Kirschner, D E HL6119/HL/NHLBI NIH HHS/United States HL68526/HL/NHLBI NIH HHS/United States Research Support, U.S. Gov't, Non-P.H.S. Research Support, U.S. Gov't, P.H.S. Germany Journal of mathematical biology J Math Biol. 2004 Feb;48(2):218-42. Epub 2003 Aug 20. PY - 2004 RN - fulltext fulltext_1208 SN - 0303-6812 (Print) 0303-6812 (Linking) SP - 218-42 ST - Macrophage response to Mycobacterium tuberculosis infection T2 - J Math Biol TI - Macrophage response to Mycobacterium tuberculosis infection UR - http://www.springerlink.com/content/bn36wd4p4f6ypk0m/ VL - 48 ID - 2447 ER - TY - JOUR AB - Molecular epidemiological studies can provide novel insights into the transmission of infectious diseases such as tuberculosis. Typically, risk factors for transmission are identified using traditional hypothesis-driven statistical methods such as logistic regression. However, limitations become apparent in these approaches as the scope of these studies expand to include additional epidemiological and bacterial genomic data. Here we examine the use of Bayesian models to analyze tuberculosis epidemiology. We begin by exploring the use of Bayesian networks (BNs) to identify the distribution of tuberculosis patient attributes (including demographic and clinical attributes). Using existing algorithms for constructing BNs from observational data, we learned a BN from data about tuberculosis patients collected in San Francisco from 1991 to 1999. We verified that the resulting probabilistic models did in fact capture known statistical relationships. Next, we examine the use of newly introduced methods for representing and automatically constructing probabilistic models in structured domains. We use statistical relational models (SRMs) to model distributions over relational domains. SRMs are ideally suited to richly structured epidemiological data. We use a data-driven method to construct a statistical relational model directly from data stored in a relational database. The resulting model reveals the relationships between variables in the data and describes their distribution. We applied this procedure to the data on tuberculosis patients in San Francisco from 1991 to 1999, their Mycobacterium tuberculosis strains, and data on contact investigations. The resulting statistical relational model corroborated previously reported findings and revealed several novel associations. These models illustrate the potential for this approach to reveal relationships within richly structured data that may not be apparent using conventional statistical approaches. We show that Bayesian methods, in particular statistical relational models, are an important tool for understanding infectious disease epidemiology. AD - Computer Science Deptartment and UMIACS, University of Maryland, College Park, MD 20742, USA. getoor@cs.umd.edu AN - 15081074 AU - Getoor, L. AU - Rhee, J. T. AU - Koller, D. AU - Small, P. DA - Mar N1 - 0933-3657 Journal Article PY - 2004 RN - fulltext fulltext_1208 SP - 233-256 ST - Understanding tuberculosis epidemiology using structured statistical models T2 - Artificial Intelligence in Medicine TI - Understanding tuberculosis epidemiology using structured statistical models UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=15081074http://ac.els-cdn.com/S0933365703001337/1-s2.0-S0933365703001337-main.pdf?_tid=26f9353e-6b36-11e2-b271-00000aab0f6c&acdnat=1359589290_10f521802b4cf63c00c720e01649cbab VL - 30 ID - 2448 ER - TY - JOUR AB - Population patterns of infection are determined largely by susceptibility to infection. Infection and vaccination induce an immune response that, typically, reduces susceptibility to subsequent infections. With a general epidemic model, we detect a 'reinfection threshold', above which reinfection is the principal type of transmission and, consequently, infection levels are much higher and vaccination fails. The model is further developed to address human tuberculosis (TB) and the impact of vaccination. The bacille Calmette-Guerin (BCG) is the only vaccine in current use against TB, and there is no consensus about its usefulness. Estimates of protection range from 0 to 80%, and this variability is aggravated by an association between low vaccine efficacy and high prevalence of the disease. We propose an explanation based on three postulates: (i) the potential for transmission varies between populations, owing to differences in socio-economic and environmental factors; (ii) exposure to mycobacteria induces an immune response that is partially protective against reinfection; and (iii) this protection is not significantly improved by BCG vaccination. These postulates combine to reproduce the observed trends, and this is attributed to a reinfection threshold intrinsic to the transmission dynamics. Finally, we demonstrate how reinfection thresholds can be manipulated by vaccination programmes, suggesting that they have a potentially powerful role in global control. AD - Instituto Gulbenkian de Ciencia, Apartado 14, 2781-901 Oeiras, Portugal. ggomes@igc.gulbenkian.pt AN - 15156920 AU - Gomes, M. G. AU - Franco, A. O. AU - Gomes, M. C. AU - Medley, G. F. DA - Mar 22 DO - 10.1098/rspb.2003.2606 ET - 05/26 J2 - Proceedings. Biological sciences / The Royal Society KW - BCG Vaccine/*immunology Disease Transmission, Infectious/*prevention & control Humans *Models, Biological Mycobacterium Infections/*immunology Tuberculosis/epidemiology/immunology/*transmission LA - eng M3 - Research Support, Non-U.S. Gov't N1 - Gomes, M Gabriela M Franco, Ana O Gomes, Manuel C Medley, Graham F England Proc Biol Sci. 2004 Mar 22;271(1539):617-23. PY - 2004 RN - fulltext fulltext_1208 SN - 0962-8452 (Print) 0962-8452 (Linking) SP - 617-23 ST - The reinfection threshold promotes variability in tuberculosis epidemiology and vaccine efficacy T2 - Proc Biol Sci TI - The reinfection threshold promotes variability in tuberculosis epidemiology and vaccine efficacy UR - http://www.ncbi.nlm.nih.gov/pubmed/15156920http://pubmedcentralcanada.ca/picrender.cgi?accid=PMC1691632&blobtype=pdf VL - 271 ID - 2449 ER - TY - JOUR AN - 13919 AU - Gomes, M. G. M. AU - White, L. J. AU - Medley, G. F. KW - immunity infection interventions models protection reinfection tuberculosis vaccination vaccine vaccine development N1 - IN FILE TB Intervention strategies Vaccine development No sub-heading Vacc dev - misc PY - 2004 RN - fulltext fulltext_1208 SP - 539-549 ST - Infection, reinfection, and vaccination under suboptimal immune protection: epidemiological perspectives T2 - J.Theor.Biol. TI - Infection, reinfection, and vaccination under suboptimal immune protection: epidemiological perspectives UR - file://C:\literature_pdf\rm13919.pdfhttp://ac.els-cdn.com/S0022519304000748/1-s2.0-S0022519304000748-main.pdf?_tid=a369897a-6b36-11e2-a468-00000aacb362&acdnat=1359589498_229e65e7b4d531f910339318b91df69b VL - 228 ID - 2450 ER - TY - JOUR AB - BACKGROUND: Moxifloxacin is a quinolone antimicrobial that has potent activity against Mycobacterium tuberculosis. To optimize moxifloxacin dose and dose regimen, pharmacodynamic antibiotic-exposure targets associated with maximal microbial kill and complete suppression of drug resistance in M. tuberculosis must be identified. METHODS: We used a novel in vitro pharmacodynamic infection model of tuberculosis in which we exposed M. tuberculosis to moxifloxacin with a pharmacokinetic half-life of decline similar to that encountered in humans. Data obtained from this model were mathematically modeled, and the drug-exposure breakpoint associated with the suppression of drug resistance was determined. Monte-Carlo simulations were performed to determine the probability that 10,000 clinical patients taking different doses of moxifloxacin would achieve or exceed the drug-exposure breakpoint needed to suppress resistance to moxifloxacin in M. tuberculosis. RESULTS: The ratio of the moxifloxacin-free (non-protein-bound) area under the concentration-time curve from 0 to 24 h to the minimum inhibitory concentration associated with complete suppression of the drug-resistant mutant population was 53. For patients taking moxifloxacin doses of 400, 600, or 800 mg/day, the calculated target-attainment rates to suppress drug resistance were 59%, 86%, and 93%, respectively. CONCLUSION: A moxifloxacin dose of 800 mg/day is likely to achieve excellent M. tuberculosis microbial kill and to suppress drug resistance. However, tolerability of this higher dose is still unknown. AD - Emerging Infections and Host Defense Section, Ordway Research Institute, Albany, New York 12208, USA. AN - 15478070 AU - Gumbo, T. AU - Louie, A. AU - Deziel, M. R. AU - Parsons, L. M. AU - Salfinger, M. AU - Drusano, G. L. DA - Nov 1 DO - JID32536 [pii] 10.1086/424849 [doi] DP - Nlm ET - 10/13 KW - Antitubercular Agents/administration & dosage/pharmacokinetics/ pharmacology/therapeutic use Aza Compounds/administration & dosage/ pharmacokinetics/ pharmacology/therapeutic use Colony Count, Microbial Drug Resistance, Bacterial Humans Microbial Sensitivity Tests Models, Biological Monte Carlo Method Mycobacterium tuberculosis/ drug effects/growth & development Quinolines/administration & dosage/ pharmacokinetics/ pharmacology/therapeutic use Tuberculosis/drug therapy/microbiology L1 - internal-pdf://0928176041/Gumbo-2004-Selection of a moxifloxacin dose th.pdf LA - eng N1 - Gumbo, Tawanda Louie, Arnold Deziel, Mark R Parsons, Linda M Salfinger, Max Drusano, George L Research Support, Non-U.S. Gov't United States The Journal of infectious diseases J Infect Dis. 2004 Nov 1;190(9):1642-51. Epub 2004 Sep 24. PY - 2004 RN - fulltext fulltext_1208 SN - 0022-1899 (Print) 0022-1899 (Linking) SP - 1642-51 ST - Selection of a moxifloxacin dose that suppresses drug resistance in Mycobacterium tuberculosis, by use of an in vitro pharmacodynamic infection model and mathematical modeling T2 - J Infect Dis TI - Selection of a moxifloxacin dose that suppresses drug resistance in Mycobacterium tuberculosis, by use of an in vitro pharmacodynamic infection model and mathematical modeling UR - http://jid.oxfordjournals.org/content/190/9/1642.full.pdf https://watermark.silverchair.com/190-9-1642.pdf?token=AQECAHi208BE49Ooan9kkhW_Ercy7Dm3ZL_9Cf3qfKAc485ysgAAAc8wggHLBgkqhkiG9w0BBwagggG8MIIBuAIBADCCAbEGCSqGSIb3DQEHATAeBglghkgBZQMEAS4wEQQMyF8_epcQm4VNYrpDAgEQgIIBggsX4qnr8_dvV6PFHHMaK79tMwdbCBgxmUcnG9Mkpr5--AkWxyfm-tg4QaFZBWk6El4o6L0rexo7jSSA0Uolj2gXoiQWqFFCIr9_3kzZLtLFznpzSHcE7xJ47RD5BF6lOtSwY9l2ijXqz2bVjQJ5nL-7ZSKBf8LjhjGhHHc94u6C5lIakawUzBD-tEQ1qj-OdJ8G0Qlt9k6gvelh_NpzNYe2cjidd1aKdWu6tkptoz-CwwNIg5N2CjPBivzIln-ZQYrZT_XKxYj3J4oCFvSu0es2VVGG89ztsFcTymOhetdlTGimqi85tOtFxRBy8-jgjUF6RRDZgCenSqZl16FIJrv-2UN4kpSAvYLweepYk7SSOkjegO3g7olOAiBBOUVVy6-zL__Fe_DvicoFDPs5L8397nrTNHK0gpe8lGoSxl_ABJxVZWjWRt95AI6fZYbVOv-E_qJkgbUFTJ_QFIcleHrmo2xy9kwqNmgRMRRqprmmB4oSpIj0Xzt57OZ8SjWcWckf VL - 190 ID - 2451 ER - TY - JOUR AU - Guwatudde, D. AU - Debanne, S. M. AU - Diaz, M. AU - King, C. AU - Whalen, C. C. DO - 10.1016/j.ypmed.2004.04.008 KW - Tuberculosis preventive therapy Tuberculosis control Sub-Saharan Africa HIV-infection Deterministic model PY - 2004 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 0091-7435 SP - 1036-1046 ST - A re-examination of the potential impact of preventive therapy on the public health problem of tuberculosis in contemporary sub-Saharan Africa T2 - Preventive Medicine TI - A re-examination of the potential impact of preventive therapy on the public health problem of tuberculosis in contemporary sub-Saharan Africa UR - http://www.sciencedirect.com/science/article/pii/S0091743504002117http://ac.els-cdn.com/S0091743504002117/1-s2.0-S0091743504002117-main.pdf?_tid=88ab7fb2ac53ae8c8768c7226bf2893a&acdnat=1345012430_531a7dd98abd3bed8080cd1e63a4eaa5 VL - 39 ID - 2452 ER - TY - JOUR AB - Two months of treatment with rifampin-pyrazinamide (RZ) and 9 months of treatment with isoniazid are both recommended for treatment of latent tuberculosis infection in adults without human immunodeficiency virus infection, but the relative cost-effectiveness of these 2 treatments is unknown. We used a Markov model to conduct a cost-effectiveness analysis to assess the impact on life expectancy and costs based on the results of a recent clinical trial that compared the rates of adverse events and completion of the 2 treatment regimens. Compared with no treatment, both regimens increased life expectancy by 1.2 years, but RZ cost 273 dollars more per patient. Sensitivity analyses showed that, assuming equal efficacy between the 2 regimens, there was no threshold completion rate for RZ at which the 2 treatments would be of equal net cost. Under most circumstances, treatment of latent tuberculosis infection with isoniazid is cost-saving than treatment with RZ. AU - Jasmer, R. M. AU - Snyder, D. C. AU - Saukkonen, J. J. AU - Hopewell, P. C. AU - Bernardo, J. AU - King, M. D. AU - Kawamura, L. M. AU - Daley, C. L. AU - Short-Course, Rifampin AU - Pyrazinamide for Tuberculosis Infection Study, Investigators DO - 10.1086/380966 IS - 3 KW - Adolescent Adult Antitubercular Agents/adverse effects/*economics/t Cost Savings Cost-Benefit Analysis Costs and Cost Analysis Humans Isoniazid/adverse effects/*economics/therapeutic u Pyrazinamide/adverse effects/*economics/therapeuti Rifampin/adverse effects/*economics/therapeutic us Tuberculosis/*drug therapy L1 - file:///C:/Users/James/AppData/Local/Mendeley Ltd/Mendeley Desktop/Downloaded/Jasmer-2004-Short-course rifampin and pyrazin1.pdf N1 - Jasmer, Robert M Snyder, David C Saukkonen, Jussi J Hopewell, Philip C Bernardo, John King, Mark D Kawamura, L Masae Daley, Charles L eng PY - 2004 SN - 1537-6591 (Electronic) 1058-4838 (Linking) SP - 363-369 ST - Short-course rifampin and pyrazinamide compared with isoniazid for latent tuberculosis infection: a cost-effectiveness analysis based on a multicenter clinical trial T2 - Clin Infect Dis TI - Short-course rifampin and pyrazinamide compared with isoniazid for latent tuberculosis infection: a cost-effectiveness analysis based on a multicenter clinical trial UR - http://www.ncbi.nlm.nih.gov/pubmed/14727206 http://cid.oxfordjournals.org/content/38/3/363.full.pdf http://cid.oxfordjournals.org/content/38/3/363.full.pdf#page=1&view=FitH http://cid.oxfordjournals.org/content/38/3/363.long VL - 38 ID - 3774 ER - TY - JOUR AB - This article estimates the risk of tuberculosis (TB) transmission on a typical commercial airliner using a simple one box model (OBM) and a sequential box model (SBM). We used input data derived from an actual TB exposure on an airliner, and we assumed a hypothetical scenario that a highly infectious TB source case (i.e., 108 infectious quanta per hour) travels as a passenger on an 8.7-hour flight. We estimate an average risk of TB transmission on the order of 1 chance in 1,000 for all passengers using the OBM. Applying the more realistic SBM, we show that the risk and incidence decrease sharply in a stepwise fashion in cabins downstream from the cabin containing the source case assuming some potential for airflow from more contaminated to less contaminated cabins. We further characterized spatial variability in the risk within the cabin by modeling a previously reported TB outbreak in an airplane to demonstrate that the TB cases occur most likely within close proximity of the source TB patient. AD - Environmental Sciences, University of Texas Health Science Center at Houston, School of Public Health, Houston, TX 77225, USA. gwangpyo.ko@uth.tmc.edu AN - 15078308 AU - Ko, G. AU - Thompson, K. M. AU - Nardell, E. A. DA - Apr DO - 10.1111/j.0272-4332.2004.00439.x [doi] RISK439 [pii] DP - Nlm ET - 04/14 KW - Aerospace Medicine Air Microbiology Aviation Humans Models, Biological Risk Risk Assessment Tuberculosis, Pulmonary/ transmission Ventilation LA - eng N1 - Ko, Gwangpyo Thompson, Kimberly M Nardell, Edward A United States Risk analysis : an official publication of the Society for Risk Analysis Risk Anal. 2004 Apr;24(2):379-88. PY - 2004 RN - fulltext fulltext_1208 SN - 0272-4332 (Print) 0272-4332 (Linking) SP - 379-88 ST - Estimation of tuberculosis risk on a commercial airliner T2 - Risk Anal TI - Estimation of tuberculosis risk on a commercial airliner UR - http://onlinelibrary.wiley.com/doi/10.1111/j.0272-4332.2004.00439.x/abstract VL - 24 ID - 2453 ER - TY - JOUR AB - A key issue for the study of tuberculosis is to understand why individuals infected with Mycobacterium tuberculosis (Mtb) experience different clinical outcomes. To better understand the dynamics of Mtb infection and immunity, we have previously developed a temporal mathematical model that qualitatively and quantitatively characterizes the cellular and cytokine control network during infection. In this work we extend that model to a two compartmental model to capture the important processes of cellular activation and priming that occur between the lung and the nearest draining lymph node. We are able to reproduce typical disease progression scenarios including primary infection, latency or clearance. Then we use the model to predict key processes determining these different disease trajectories (i.e. identify bifurcation parameters), suggesting directions for further basic science study and potential new treatment strategies. AD - Department of Microbiology and Immunology, University of Michigan Medical School, 6730 Medical Science Building II, Ann Arbor, MI 48109-0620, USA. simeonem@umich.edu AN - 15038983 AU - Marino, S. AU - Kirschner, D. E. DA - Apr 21 DO - 10.1016/j.jtbi.2003.11.023 [doi] S0022519303004429 [pii] DP - Nlm ET - 03/25 KW - Cytokines/immunology Dendritic Cells/immunology Disease Progression Humans Immunity/immunology Lung/ immunology Lymph Nodes/ immunology Lymphocytes/immunology Mathematics Models, Immunological Mycobacterium tuberculosis/ immunology Tuberculosis/drug therapy/ immunology LA - eng N1 - Marino, Simeone Kirschner, Denise E R01 HL68526/HL/NHLBI NIH HHS/United States Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. England Journal of theoretical biology J Theor Biol. 2004 Apr 21;227(4):463-86. PY - 2004 RN - fulltext fulltext_1208 SN - 0022-5193 (Print) 0022-5193 (Linking) SP - 463-86 ST - The human immune response to Mycobacterium tuberculosis in lung and lymph node T2 - J Theor Biol TI - The human immune response to Mycobacterium tuberculosis in lung and lymph node UR - http://ac.els-cdn.com/S0022519303004429/1-s2.0-S0022519303004429-main.pdf?_tid=463df9c23cd467c72c7b22525a29a48e&acdnat=1345012650_2ba45ca5231c150bbe59251fbf62022d VL - 227 ID - 2454 ER - TY - JOUR AB - Mycobacterium tuberculosis (Mtb) is an extraordinarily successful human pathogen, one of the major causes of death by infectious disease worldwide. A key issue for the study of tuberculosis is to understand why individuals infected with Mtb experience different clinical outcomes. To better understand the dynamics of Mtb infection and immunity, we coupled nonhuman primate experiments with a mathematical model we previously developed that qualitatively and quantitatively captures important processes of cellular priming and activation. These processes occur between the lung and the nearest draining lymph node where the key cells mediating this process are the dendritic cells (DC). The nonhuman primate experiments consist of bacteria and cell numbers from tissues of 17 adult cynomolgus macaques (Macaca fascicularis) that were infected with Mtb strain Erdman (similar to25 CFU/animal via bronchoscope). The main result of this work is that delays in either DC migration to the draining lymph node or T cell trafficking to the site of infection can alter the outcome of Mtb infection, defining progression to primary disease or latent infection and reactivated tuberculosis. Our results also support the idea that the development of a new generation of treatment against Mtb should optimally elicit a fast DC turnover at the site of infection, as well as strong activation of DCs for maximal Ag presentation and production of key cytokines. This will induce the most protective T cell response. AD - Univ Michigan, Sch Med, Dept Microbiol & Immunol, Ann Arbor, MI 48109 USA Univ Pittsburgh, Dept Mol Genet & Biochem, Sch Med, Pittsburgh, PA 15260 USA Univ Pittsburgh, Grad Sch Publ Hlth, Dept Infect Dis & Microbiol, Pittsburgh, PA 15261 USA AN - WOS:000222170900063 AU - Marino, S. AU - Pawar, S. AU - Fuller, C. L. AU - Reinhart, T. A. AU - Flynn, J. L. AU - Kirschner, D. E. DA - Jul 1 IS - 1 J2 - J Immunol KW - cd8(+) t-cells chemokine receptor expression necrosis-factor-alpha in-vivo interferon-gamma bronchoalveolar lavage sensitivity analysis ifn-gamma endogenous reactivation pulmonary tuberculosis LA - English N1 - 831cq Times Cited:71 Cited References Count:106 PY - 2004 SN - 0022-1767 SP - 494-506 ST - Dendritic cell trafficking and antigen presentation in the human immune response to Mycobacterium tuberculosis T2 - Journal of Immunology TI - Dendritic cell trafficking and antigen presentation in the human immune response to Mycobacterium tuberculosis UR - ://WOS:000222170900063 VL - 173 ID - 2231 ER - TY - JOUR AB - The importance of exogenous reinfection versus endogenous reactivation for the resurgence of tuberculosis (TB) has been a matter of ongoing debate. Previous mathematical models of TB give conflicting results on the possibility of multiple stable equilibria in the presence of reinfection, and hence the failure to control the disease even when the basic reproductive number is less than unity. The present study reconsiders the effect of exogenous reinfection, by extending previous studies to incorporate a generalized rate of reinfection as a function of the number of actively infected individuals. A mathematical model is developed to include all possible routes to the development of active TB (progressive primary infection, endogenous reactivation, and exogenous reinfection). The model is qualitatively analyzed to show the existence of multiple equilibria under realistic assumptions and plausible range of parameter values. Two examples, of unbounded and saturated incidence rates of reinfection, are given, and simulation results using estimated parameter values are presented. The results reflect exogenous reinfection as a major cause of TB emergence, especially in high prevalence areas, with important public health implications for controlling its spread. AD - Natl Res Council Canada, Inst Biodiagnost, Winnipeg, MB R3B 1Y6, Canada AN - WOS:000222829400006 AU - Moghadas, S. M. AU - Alexander, M. E. DA - Jun DO - Doi 10.1142/S0218339004001063 IS - 2 J2 - J Biol Syst KW - basic reproductive number epidemic models equilibria exogenous reinfection stability tuberculosis mycobacterium-tuberculosis epidemic model disease transmission backward bifurcation control strategies infection prevalence equilibria dynamics hiv LA - English N1 - 840am Times Cited:5 Cited References Count:39 PY - 2004 SN - 0218-3390 SP - 231-247 ST - Exogenous reinfection and resurgence of tuberculosis: A theoretical framework T2 - Journal of Biological Systems TI - Exogenous reinfection and resurgence of tuberculosis: A theoretical framework UR - ://WOS:000222829400006 VL - 12 ID - 4834 ER - TY - JOUR AB - The purposes of this study are to predict the future trend of drug-sensitive and resistant tuberculosis (TB) in Thailand, and to assess the impact of different control strategies on the generation of drug resistant TB, through the use of mathematical analysis. We assume that the present status of TB and the emergence of drug-resistant TB in Thailand are the consequence of past epidemics. Control strategies in the model are defined by specifying the value of the effective treatment rate (baseline value = 0.74) and the relative treatment efficacy (baseline value = 0.84). It is predicted that the total number of new TB cases would continue to decrease at the current level of intervention. Although a dramatic decline in the incidence rate of drug-sensitive cases is expected, drug-resistant cases are predicted to increase gradually, so that more than half of the TB strains would not be drug-sensitive after 2020. The prediction is not greatly altered by improving the interventions. They could, however, delay the emergence of drug-resistant strains for a few years. Our study demonstrates it would be impossible to avoid the continued emergence of drug-resistant TB in the future. It is pointed out that there are urgent needs to ensure adequate supervision and monitoring, to insure treatment of 100% of the targeted population with Directly Observed Therapy. AD - Department of Mathematics, Faculty of Science, Mahidol University, Bangkok, Thailand. Nishiurah@aol.com AN - 15689082 AU - Nishiura, H. AU - Patanarapelert, K. AU - Tang, I. M. DA - Sep DP - Nlm ET - 02/04 KW - Antibiotics, Antitubercular/pharmacology/therapeutic use Chemoprevention Communicable Disease Control Directly Observed Therapy Drug Resistance, Multiple, Bacterial Forecasting Humans Incidence Models, Theoretical Mycobacterium tuberculosis/ drug effects Rifampin/pharmacology/therapeutic use Thailand/epidemiology Tuberculosis, Multidrug-Resistant/drug therapy/ epidemiology/prevention & control L1 - internal-pdf://2935527750/27-3243.pdf LA - eng N1 - Nishiura, Hiroshi Patanarapelert, Kot Tang, I Ming Thailand The Southeast Asian journal of tropical medicine and public health Southeast Asian J Trop Med Public Health. 2004 Sep;35(3):649-56. PY - 2004 RN - fulltext fulltext_1208 SN - 0125-1562 (Print) 0125-1562 (Linking) SP - 649-56 ST - Predicting the future trend of drug-resistant tuberculosis in Thailand: assessing the impact of control strategies T2 - Southeast Asian J Trop Med Public Health TI - Predicting the future trend of drug-resistant tuberculosis in Thailand: assessing the impact of control strategies VL - 35 ID - 2455 ER - TY - JOUR AB - This paper is devoted to the construction of the mathematical model of the tuberculosis morbidity dynamics. The model takes into account the peculiarities of morbidity epidemiology and its control. The model is adjusted to the data collected in the Orlovskaya oblast. The results obtained will be used for the analysis of the epidemiological situation and designing the effective strategy of tuberculosis control. AD - Moscow Med Acad, IM Sechenov Res Inst Phthisiopulmon, Moscow 127994, Russia Russian Acad Sci, Inst Numer Math, Moscow 119991, Russia AN - WOS:000223636500004 AU - Perelman, M. I. AU - Marchuk, G. I. AU - Borisov, S. E. AU - Kazennykh, B. Y. AU - Avilov, K. K. AU - Karkach, A. S. AU - Romanyukha, A. A. DO - Doi 10.1163/1569398041974905 IS - 4 J2 - Russ J Numer Anal M KW - resistant impact hiv LA - English N1 - 850tu Times Cited:7 Cited References Count:8 PY - 2004 SN - 0927-6467 SP - 305-314 ST - Tuberculosis epidemiology in Russia: the mathematical model and data analysis T2 - Russian Journal of Numerical Analysis and Mathematical Modelling TI - Tuberculosis epidemiology in Russia: the mathematical model and data analysis UR - ://WOS:000223636500004 https://www.degruyter.com/view/j/rnam.2004.19.issue-4/1569398041974905/1569398041974905.xml VL - 19 ID - 4835 ER - TY - JOUR AB - To determine whether polymerase chain reaction (PCR) testing in the initial diagnosis of pulmonary tuberculosis (TB) is cost-effective in a low-prevalence population, an economic evaluation was carried out between the smear and culture (NOPCR) and smear, culture and PCR (+PCR) strategies. A decision tree model based on retrospective laboratory data was developed to assess the strategies of testing patients with suspicion of TB. Direct healthcare costs prior to confirmation of TB or nontuberculous mycobacteria by PCR or culture were included. Effectiveness was measured by the probability of correct treatment and isolation decisions. In the baseline situation NOPCR costs Euro 29.50 less than the +PCR strategy per patient tested. According to sensitivity analyses, reducing PCR test price, shortening test performance time or increasing the proportion of smear-positive patients in the tested population would contribute to cost savings with the +PCR strategy. Routine polymerase chain reaction testing of all specimens from suspected tuberculosis patients in a low-prevalence population was not cost-saving. When the polymerase chain reaction assay was applied only to smear-positive sputum specimens, the smear and culture strategy was clearly dominated by it, i.e. the polymerase chain reaction smear-positive sputum strategy was less costly and more effective in producing correct treatment decisions and isolations. AD - Dept of Pulmonary Diseases, Tampere University Hospital, Tampere, Finland. iiris.rajalahti@kolumbus.fi AN - 15065837 AU - Rajalahti, I. AU - Ruokonen, E. L. AU - Kotomaki, T. AU - Sintonen, H. AU - Nieminen, M. M. DA - Mar DP - Nlm ET - 04/07 J2 - The European respiratory journal : official journal of the European Society for Clinical Respiratory Physiology KW - Cost-Benefit Analysis Decision Trees Finland/epidemiology Health Care Costs/statistics & numerical data Humans Incidence Polymerase Chain Reaction/ economics Prevalence Specimen Handling Sputum/microbiology Tuberculosis, Pulmonary/ diagnosis/economics/epidemiology LA - eng N1 - Rajalahti, I Ruokonen, E L Kotomaki, T Sintonen, H Nieminen, M M Research Support, Non-U.S. Gov't Denmark Eur Respir J. 2004 Mar;23(3):446-51. PY - 2004 RN - fulltext fulltext_1208 SN - 0903-1936 (Print) 0903-1936 (Linking) SP - 446-51 ST - Economic evaluation of the use of PCR assay in diagnosing pulmonary TB in a low-incidence area T2 - Eur Respir J TI - Economic evaluation of the use of PCR assay in diagnosing pulmonary TB in a low-incidence area UR - http://erj.ersjournals.com/content/23/3/446.full.pdf VL - 23 ID - 2456 ER - TY - JOUR AB - Infection with Mycobacterium tuberculosis is a major world health problem. An estimated 2 billion people are presently infected and the disease causes approximately 3 million deaths per year. After bacteria are inhaled into the lung, a complex immune response is triggered leading to the formation of multicellular structures termed granulomas. It is believed that the collection of host granulomas either contain bacteria resulting in a latent infection or are unable to do so, leading to active disease. Thus, understanding granuloma formation and function is essential for improving both diagnosis and treatment of tuberculosis. Granuloma formation is a complex spatio-temporal system involving interactions of bacteria, specific immune cells, including macrophages, CD4+ and CD8+ T cells, as well as immune effectors such as chemokine and cytokines. To study this complex dynamical system we have developed an agent-based model of granuloma formation in the lung. This model combines continuous representations of chemokines with discrete agent representations of macrophages and T cells in a cellular automata-like environment. Our results indicate that key host elements involved in granuloma formation are chemokine diffusion, prevention of macrophage overcrowding within the granuloma, arrival time, location and number of T cells within the granuloma, and an overall host ability to activate macrophages. Interestingly, a key bacterial factor is its intracellular growth rate, whereby slow growth actually facilitates survival. AD - Department of Microbiology and Immunology, University of Michigan, Ann Arbor, MI 48109, USA. AN - 15501468 AU - Segovia-Juarez, J. L. AU - Ganguli, S. AU - Kirschner, D. DA - Dec 7 DO - 10.1016/j.jtbi.2004.06.031 ET - 10/27 J2 - Journal of theoretical biology KW - Chemokines/immunology Granuloma/*immunology Humans Lung/*immunology Lymphocyte Activation Macrophage Activation Macrophages/immunology *Models, Immunological *Mycobacterium tuberculosis T-Lymphocytes/immunology Tuberculosis/*immunology LA - eng M3 - Research Support, U.S. Gov't, P.H.S. N1 - Segovia-Juarez, Jose L Ganguli, Suman Kirschner, Denise R01HL68526/HL/NHLBI NIH HHS/ England J Theor Biol. 2004 Dec 7;231(3):357-76. PY - 2004 RN - fulltext fulltext_1208 SN - 0022-5193 (Print) 0022-5193 (Linking) SP - 357-76 ST - Identifying control mechanisms of granuloma formation during M. tuberculosis infection using an agent-based model T2 - J Theor Biol TI - Identifying control mechanisms of granuloma formation during M. tuberculosis infection using an agent-based model UR - http://www.ncbi.nlm.nih.gov/pubmed/15501468 VL - 231 ID - 2458 ER - TY - JOUR AB - the extent to which reinfection of latently infected individuals contributes to the dynamics of tuberculosis (TB) epidemics. In this study we present an epidemiological model of Mycobacterium tuberculosis infection that includes the process of reinfection. Using analysis and numerical simulations, we observe the effect that varying levels of reinfection has on the qualitative dynamics of the TB epidemic. We examine cases of the model both with and without treatment of actively infected individuals. Next, we consider a variation of the model describing a heterogeneous population, stratified by susceptibility to TB infection. Results show that a threshold level of reinfection exists in all cases of the model. Beyond this threshold, the dynamics of the model are described by a backward bifurcation. Uncertainty analysis of the parameters shows that this threshold is too high to be attained in a realistic epidemic. However, we show that even for sub-threshold levels of reinfection, including reinfection in the model changes dynamic behavior of the model. In particular, when reinfection is present the basic reproductive number, R(0), does not accurately describe the severity of an epidemic. AD - Department of Microbiology and Immunology, The University of Michigan Medical School, Ann Arbor, MI 48109-0620. kirschne@umich.edu. AN - 20369961 AU - Singer, B. H. AU - Kirschner, D. E. DA - Jun IS - 1 N1 - Singer, Benjamin H Kirschner, Denise E eng 2004/06/01 00:00 Math Biosci Eng. 2004 Jun;1(1):81-93. PY - 2004 SN - 1547-1063 (Print) 1547-1063 (Linking) SP - 81-93 ST - Influence of backward bifurcation on interpretation of r(0) in a model of epidemic tuberculosis with reinfection T2 - Math Biosci Eng TI - Influence of backward bifurcation on interpretation of r(0) in a model of epidemic tuberculosis with reinfection UR - https://www.ncbi.nlm.nih.gov/pubmed/20369961 VL - 1 ID - 2259 ER - TY - JOUR AB - BACKGROUND: While the pathogenesis and epidemiology of tuberculosis are well studied, relatively little is known about the evolution of the infectious agent Mycobacterium tuberculosis, especially at the within-host level. The insertion sequence IS6110 is a genetic marker that is widely used to track the transmission of tuberculosis between individuals. This and other markers may also facilitate our understanding of the disease within patients. RESULTS: This article presents three lines of evidence supporting the action of positive selection on M. tuberculosis within patients. The arguments are based on a comparison between empirical findings from molecular epidemiology, and population genetic models of evolution. Under the hypothesis of neutrality of genotypes, 1) the mutation rate of the marker IS6110 is unusually high, 2) the time it takes for substitutions to occur within patients is too short, and 3) the amount of polymorphism within patients is too low. CONCLUSIONS: Empirical observations are explained by the action of positive selection during infection, or alternatively by very low effective population sizes. I discuss the possible roles of antibiotic treatment, the host immune system and extrapulmonary dissemination in creating opportunities for positive selection. AD - School of Biotechnology and Biomolecular Sciences, University of New South Wales, NSW 2052, Australia. m.tanaka@unsw.edu.au AN - 15355550 AU - Tanaka, M. M. DA - Sep 9 N1 - 1471-2148 Journal Article PY - 2004 RN - fulltext fulltext_1208 SP - 31 ST - Evidence for positive selection on Mycobacterium tuberculosis within patients T2 - Bio Med Central Evolutionary Biology TI - Evidence for positive selection on Mycobacterium tuberculosis within patients UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=15355550 VL - 4 ID - 2459 ER - TY - JOUR AB - Developing effective tuberculosis (TB) vaccines is a high priority. We use mathematical models to predict the potential public health impact of new TB vaccines in high-incidence countries. We show that preexposure vaccines would be almost twice as effective as postexposure vaccines in reducing the number of new infections. Postexposure vaccines would initially have a substantially greater impact, compared to preexposure vaccines, on reducing the number of new cases of disease. However, the effectiveness of postexposure vaccines would diminish over time, whereas the effectiveness of preexposure vaccines would increase. Thus, after 20 to 30 years, post- or preexposure vaccination campaigns would be almost equally effective in terms of cumulative TB cases prevented. Even widely deployed and highly effective (50%-90% efficacy) pre- or postexposure vaccines would only be able to reduce the number of TB cases by one third. We discuss the health policy implications of our analyses. AD - University of California-San Francisco, San Francisco, California, USA. AN - 15498152 AU - Ziv, E. AU - Daley, C. L. AU - Blower, S. DA - Sep ET - 10/23 J2 - Emerging infectious diseases KW - Disease Outbreaks Health Policy Humans Incidence Models, Theoretical Public Health Time Factors Tuberculosis/immunology/*prevention & control Tuberculosis Vaccines/*immunology LA - eng M3 - Research Support, U.S. Gov't, P.H.S. Review N1 - Ziv, Elad Daley, Charles L Blower, Sally R01 AI041935/AI/NIAID NIH HHS/ Emerg Infect Dis. 2004 Sep;10(9):1529-35. PY - 2004 RN - fulltext fulltext_1208 SN - 1080-6040 (Print) 1080-6040 (Linking) SP - 1529-35 ST - Potential public health impact of new tuberculosis vaccines T2 - Emerg Infect Dis TI - Potential public health impact of new tuberculosis vaccines UR - http://www.ncbi.nlm.nih.gov/pubmed/15498152 VL - 10 ID - 2460 ER - TY - JOUR AB - As HIV/AIDS drugs are becoming more widely available in Southern Africa, we compared the effectiveness and cost effectiveness of different treatment options, using a Markov Monte Carlo simulation model based on published estimates of disease progression, treatment effectiveness and health care costs. Cost and outcome values were discounted. Quality of life was considered. Acceptability curves summarized uncertainties. Sensitivity analyses tested assumptions. Results showed that triple antiretroviral therapy (ARV) plus antibiotics would prolong life by 6.7 undiscounted years if provided 'late' (CD4 = 200 cells/microl) and by 9.8 years if provided 'early' (CD4 = 350 cells/microl). The incremental undiscounted costs per year of life gained, compared to no preventive therapy, were $17 for isoniazid plus cotrimoxazole started late, $244 for both antibiotics started early, $2454 for ARV plus antibiotics started late and $2784 for ARV plus both antibiotics started early. The discounted incremental costs per quality adjusted life year (QALY) gained were, respectively, $29 saving, $254, $4937 and $3057. Late ARV plus both antibiotics was the strategy most likely to be cost effective if society was willing to pay more than $2000 per life year gained. Cost-effectiveness estimates were sensitive to discounting and assumed treatment costs but were less sensitive to assumed treatment effectiveness. AD - School of Medicine, University of East Anglia, UK. m.bachmann@uea.ac.uk AN - 16338768 AU - Bachmann, M. O. DA - Feb DO - 10.1080/09540120500159334 DP - Nlm ET - 12/13 J2 - AIDS care KW - AIDS-Related Opportunistic Infections/drug therapy/economics/mortality Africa, Southern/epidemiology Anti-Infective Agents/administration & dosage Anti-Retroviral Agents/economics/ therapeutic use Antitubercular Agents/administration & dosage Cost-Benefit Analysis Drug Therapy, Combination HIV Infections/ drug therapy/economics/mortality Health Care Costs/ statistics & numerical data Humans Isoniazid/administration & dosage Markov Chains Models, Statistical Monte Carlo Method Quality-Adjusted Life Years Treatment Outcome Trimethoprim-Sulfamethoxazole Combination/administration & dosage Tuberculosis/complications/drug therapy/economics LA - eng N1 - Bachmann, M O England AIDS Care. 2006 Feb;18(2):109-20. PY - 2005 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 0954-0121 (Print) 0954-0121 (Linking) SP - 109-20 ST - Effectiveness and cost effectiveness of early and late prevention of HIV/AIDS progression with antiretrovirals or antibiotics in Southern African adults T2 - AIDS Care TI - Effectiveness and cost effectiveness of early and late prevention of HIV/AIDS progression with antiretrovirals or antibiotics in Southern African adults UR - http://www.tandfonline.com/doi/pdf/10.1080/09540120500159334 VL - 18 ID - 2470 ER - TY - JOUR AB - OBJECTIVE: To assess the costs and health effects of tuberculosis control interventions in Africa and South East Asia in the context of the millennium development goals. DESIGN: Cost effectiveness analysis based on an epidemiological model. SETTING: Analyses undertaken for two regions classified by WHO according to their epidemiological grouping-Afr-E, countries in sub-Saharan Africa with very high adult and high child mortality, and Sear-D, countries in South East Asia with high adult and high child mortality. DATA SOURCES: Published studies, costing databases, expert opinion. MAIN OUTCOME MEASURES: Costs per disability adjusted life year (DALY) averted in 2000 international dollars (dollarsInt). RESULTS: Treatment of new cases of smear-positive tuberculosis in DOTS programmes cost dollarsInt6-8 per DALY averted in Afr-E and dollarsInt7 per DALY averted in Sear-D at coverage levels of 50-95%. In Afr-E, adding treatment of smear-negative and extra-pulmonary cases at a coverage level of 95% cost dollarsInt95 per DALY averted; the addition of DOTS-Plus treatment for multidrug resistant cases cost dollarsInt123. In Sear-D, these costs were dollarsInt52 and dollarsInt226, respectively. The full combination of interventions could reduce prevalence and mortality by over 50% in Sear-D between 1990 and 2010, and by almost 50% between 2000 and 2010 in Afr-E. CONCLUSIONS: DOTS treatment of new smear-positive cases is the first priority in tuberculosis control, including in countries with high HIV prevalence. DOTS treatment of smear-negative and extra-pulmonary cases and DOTS-Plus treatment of multidrug resistant cases are also highly cost effective. To achieve the millennium development goal for tuberculosis control, substantial extra investment is needed to increase case finding and implement interventions on a wider scale. AD - Institute for Medical Technology Assessment (iMTA), Erasmus Medical Centre, PO Box 1738, 3000 DR Rotterdam, Netherlands. r.baltussen@erasmusmc.nl AN - 16282379 AU - Baltussen, R. AU - Floyd, K. AU - Dye, C. DA - Dec 10 DO - 10.1136/bmj.38645.660093.68 ET - 11/12 J2 - Bmj KW - Africa/epidemiology Antitubercular Agents/economics/therapeutic use Asia, Southeastern/epidemiology Communicable Disease Control/economics/methods Cost-Benefit Analysis *Developing Countries Humans Incidence Prevalence Program Evaluation Quality-Adjusted Life Years Tuberculosis/classification/economics/*prevention & control Tuberculosis, Multidrug-Resistant/epidemiology/prevention & control L1 - internal-pdf://1107758612/Baltussen-2005-Cost effectiveness analysis of.pdf LA - eng M3 - Research Support, Non-U.S. Gov't N1 - Baltussen, Rob Floyd, Katherine Dye, Christopher England Clinical research ed. BMJ. 2005 Dec 10;331(7529):1364. Epub 2005 Nov 10. PY - 2005 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1756-1833 (Electronic) 0959-535X (Linking) SP - 1364 ST - Cost effectiveness analysis of strategies for tuberculosis control in developing countries T2 - BMJ TI - Cost effectiveness analysis of strategies for tuberculosis control in developing countries UR - http://www.ncbi.nlm.nih.gov/pubmed/16282379http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1309642/pdf/bmj33101364.pdf https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1309642/pdf/bmj33101364.pdf VL - 331 ID - 2462 ER - TY - JOUR AB - BACKGROUND: The HIV epidemic has caused a dramatic increase in tuberculosis (TB) in East and southern Africa. Several strategies have the potential to reduce the burden of TB in high HIV prevalence settings, and cost and cost-effectiveness analyses can help to prioritize them when budget constraints exist. However, published cost and cost-effectiveness studies are limited. METHODS: Our objective was to compare the cost, affordability and cost-effectiveness of seven strategies for reducing the burden of TB in countries with high HIV prevalence. A compartmental difference equation model of TB and HIV and recent cost data were used to assess the costs (year 2003 USD prices) and effects (TB cases averted, deaths averted, DALYs gained) of these strategies in Kenya during the period 2004-2023. RESULTS: The three lowest cost and most cost-effective strategies were improving TB cure rates, improving TB case detection rates, and improving both together. The incremental cost of combined improvements to case detection and cure was below USD 15 million per year (7.5% of year 2000 government health expenditure); the mean cost per DALY gained of these three strategies ranged from USD 18 to USD 34. Antiretroviral therapy (ART) had the highest incremental costs, which by 2007 could be as large as total government health expenditures in year 2000. ART could also gain more DALYs than the other strategies, at a cost per DALY gained of around USD 260 to USD 530. Both the costs and effects of treatment for latent tuberculosis infection (TLTI) for HIV+ individuals were low; the cost per DALY gained ranged from about USD 85 to USD 370. Averting one HIV infection for less than USD 250 would be as cost-effective as improving TB case detection and cure rates to WHO target levels. CONCLUSION: To reduce the burden of TB in high HIV prevalence settings, the immediate goal should be to increase TB case detection rates and, to the extent possible, improve TB cure rates, preferably in combination. Realising the full potential of ART will require substantial new funding and strengthening of health system capacity so that increased funding can be used effectively. AD - School of Mathematics, University of Southampton, Southampton, SO17 1BJ, UK. christine.currie@soton.ac.uk AN - 16343345 AU - Currie, C. S. AU - Floyd, K. AU - Williams, B. G. AU - Dye, C. DO - 1471-2458-5-130 [pii] 10.1186/1471-2458-5-130 [doi] DP - Nlm ET - 12/14 KW - AIDS-Related Opportunistic Infections/ economics/epidemiology/ prevention & control Adolescent Adult Antiretroviral Therapy, Highly Active/utilization Antitubercular Agents/therapeutic use Cost of Illness Cost-Benefit Analysis Directly Observed Therapy Female Health Care Costs/ statistics & numerical data Health Services Accessibility Humans Kenya/epidemiology Middle Aged Models, Econometric Prevalence Quality-Adjusted Life Years Tuberculosis/ economics/epidemiology/ prevention & control LA - eng N1 - Currie, Christine S M Floyd, Katherine Williams, Brian G Dye, Christopher Comparative Study Research Support, Non-U.S. Gov't England BMC public health BMC Public Health. 2005 Dec 12;5:130. PY - 2005 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1471-2458 (Electronic) 1471-2458 (Linking) SP - 130 ST - Cost, affordability and cost-effectiveness of strategies to control tuberculosis in countries with high HIV prevalence T2 - BMC Public Health TI - Cost, affordability and cost-effectiveness of strategies to control tuberculosis in countries with high HIV prevalence UR - http://www.biomedcentral.com/1471-2458/5/130http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1361804/pdf/1471-2458-5-130.pdf VL - 5 ID - 2463 ER - TY - JOUR AB - The aim of the present study was to perform a cost-effectiveness analysis in young and middle-aged adults with latent tuberculosis (TB) infection in Germany. A Markov model simulated the progression of 20- and 40-yr-old close contacts of active TB cases over 20 yrs. Health and economic outcomes of isoniazid (INH) chemoprevention versus no intervention were compared. The analysis determined the incremental cost-effectiveness ratio in terms of cost per quality-adjusted life year and the difference between numbers of TB cases and of TB-related deaths. INH chemoprevention prevented 79% of expected TB cases in both age groups, and saved 9,482 and 9,142 in the lower and higher age groups, respectively, per case prevented. Quality-adjusted life expectancy was slightly extended by 8 days in the lower age group and 7 days in the higher age group, at a cost saving of 417 and 375, respectively, per person. Annual savings were 20,862 and 18,742 per 1,000 contacts, respectively. The number needed to be treated to prevent one TB case in the lower age group was 23 and 25 in the higher age group. The programme also prevented three TB-related deaths in the younger and two in the older cohort. The results are highly sensitive to treatment-cost assumptions. In conclusion, isoniazid chemoprevention in Germany is a highly cost-effective approach for reducing the burden of tuberculosis in recently converted young and middle-aged adults. AD - School of Public Health, c/o Institute for Medical Sociology, Heinrich Heine University, Post box 101007, D-40001 Dusseldorf, Germany. Roland.Diel@uni-duesseldorf.de AN - 16135730 AU - Diel, R. AU - Nienhaus, A. AU - Schaberg, T. DA - Sep KW - Adolescent Adult Antitubercular Agents/administration & dosage/economics/*therapeutic use Carrier State/*prevention & control/transmission Chemoprevention/economics Contact Tracing Cost-Benefit Analysis Germany *Health Care Costs Health Status Humans Isoniazid/administration & dosage/economics/*therapeutic use Markov Chains Middle Aged Quality-Adjusted Life Years Treatment Outcome Tuberculosis/mortality/*prevention & control/transmission N1 - 0903-1936 Journal Article PY - 2005 RN - fulltext fulltext_1208 SP - 465-473 ST - Cost-effectiveness of isoniazid chemoprevention in close contacts T2 - European Respiratory Journal TI - Cost-effectiveness of isoniazid chemoprevention in close contacts UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=16135730 VL - 26 ID - 2464 ER - TY - JOUR AU - Gammack, D. AU - Ganguli, S. AU - Marino, S. AU - Segovia-Juarez, J. AU - Kirschner, D. E. PY - 2005 RN - fulltext fulltext_1208 SN - 1540-3459 SP - 312-345 ST - Understanding the immune response in tuberculosis using different mathematical models and biological scales T2 - Multiscale Modeling and Simulation TI - Understanding the immune response in tuberculosis using different mathematical models and biological scales VL - 3 ID - 2465 ER - TY - JOUR AB - The immune response to Mycobacterium tuberculosis infection (Mtb) is the formation of unique lesions, called granulomas. How well these granulomas form and function is a key issue that might explain why individuals experience different disease outcomes. The spatial structures of these granulomas are not well understood. In this paper, we use a metapopulation framework to develop a spatio-temporal model of the immune response to Mtb. Using this model, we are able to investigate the spatial organization of the immune response in the lungs to Mtb. We identify both host and pathogen factors that contribute to successful infection control. Additionally, we identify specific spatial interactions and mechanisms important for successful granuloma formation. These results can be further studied in the experimental setting. AD - Biosystems Group, University of California, San Francisco, 513 Parnassus Ave., San Francisco, CA 94143. sganguli@itsa.ucsf.edu. AN - 20369939 AU - Ganguli, S. AU - Gammack, D. AU - Kirschner, D. E. DO - 040579197 [pii] LA - eng N1 - Ganguli, Suman Gammack, David Kirschner, Denise E United States Mathematical biosciences and engineering : MBE Math Biosci Eng. 2005 Jul;2(3):535-60. PY - 2005 RN - fulltext fulltext_1208 SN - 1547-1063 (Print) 1547-1063 (Linking) SP - 535-560 ST - A metapopulation model of granuloma formation in the lung during infection with mycobacterium tuberculosis T2 - Mathematical Biosciences and Engineering TI - A metapopulation model of granuloma formation in the lung during infection with mycobacterium tuberculosis UR - http://www.ncbi.nlm.nih.gov/pubmed/20369939 VL - 2 ID - 2466 ER - TY - JOUR AB - In this paper, a nonlinear mathematical model is proposed for the transmission dynamics of HIV and a curable TB pathogen within a population of varying size. In the model, we have divided the population into four sub classes of susceptibles, TB infectives, HIV infectives and that of AIDS patients. The model exhibits four equillibria namely, a disease free, HIV free, TB free and a co?infection equilibrium. The model has been studied qualitatively using stability theory of nonlinear differential equations. It is shown that the positive co?infection equilibrium is always locally stable but it may become globally stable under certain conditions showing that the disease becomes endemic due to constant migration of the population into the habitat. A numerical study of the model is also performed to investigate the influence of certain key parameters on the spread of the disease. AU - Naresh, R. AU - Tripathi, A. DA - 2005/01/01 DO - 10.1080/13926292.2005.9637287 PY - 2005 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1392-6292 SP - 275-286 ST - Modelling and analysis of HIV‐TB co‐infection in a variable size population T2 - Mathematical Modelling and Analysis TI - Modelling and analysis of HIV‐TB co‐infection in a variable size population UR - http://www.tandfonline.com/doi/abs/10.1080/13926292.2005.9637287 VL - 10 Y2 - 2012/08/10 ID - 2467 ER - TY - JOUR AB - OBJECTIVE: To evaluate cost-effective screening and treatment strategies for healthcare workers (HCWs) at risk for tuberculosis exposure. DESIGN: A Markov model was developed to track three hypothetical cohorts of HCWs at low, moderate, and high risk for tuberculosis exposure. For those found to be tuberculin reactors at entry, the choice was for isoniazid treatment or no treatment. For those without tuberculin reactivity, the choice of screening intervals was 6 months, 1 year, 2 years, or 5 years. Outcomes measured were tuberculosis cases, death, life expectancy, and cost. Assumptions were derived from published data and analyses. RESULTS: Treatment of initial reactors with isoniazid in all three risk groups was associated with a net savings of $14,800 to $15,700 for each tuberculosis case prevented. For those without evidence of infection at entry, the most cost-effective screening interval was 1 year for high-risk groups, 2 years for moderate-risk groups, and 5 years for low-risk groups, with a net savings $0.20 to $26 per HCW per year. Screening at a more frequent interval was still cost-effective. CONCLUSIONS: For HCWs found to be tuberculin reactors, treatment of their latent infection is to their benefit and is associated with a net cost-savings. Regular tuberculin screening of HCWs can be cost-effective or result in a net cost-savings. Each institution could use its own skin test surveillance data to create an optimum screening program for its employees. However, for most HCWs, a 1-year screening interval would be a cost-effective and safe choice. AD - Santa Clara Valley Medical Center, San Jose, USA. AN - 15636292 AU - Salpeter, S. R. AU - Salpeter, E. E. DA - Dec DO - ICHE9433 [pii] 10.1086/502343 ET - 01/08 KW - Antitubercular Agents/therapeutic use Cost-Benefit Analysis *Decision Trees *Health Personnel Humans Isoniazid/therapeutic use Markov Chains *Mass Screening Risk Factors Tuberculin Test Tuberculosis/diagnosis/drug therapy/*economics LA - eng N1 - Salpeter, Shelley R Salpeter, Edwin E Evaluation Studies Research Support, Non-U.S. Gov't United States Infection control and hospital epidemiology : the official journal of the Society of Hospital Epidemiologists of America Infect Control Hosp Epidemiol. 2004 Dec;25(12):1056-61. PY - 2005 RN - fulltext fulltext_1208 SN - 0899-823X (Print) 0899-823X (Linking) SP - 1056-61 ST - Screening and treatment of latent tuberculosis among healthcare workers at low, moderate, and high risk for tuberculosis exposure: a cost-effectiveness analysis T2 - Infect Control Hosp Epidemiol TI - Screening and treatment of latent tuberculosis among healthcare workers at low, moderate, and high risk for tuberculosis exposure: a cost-effectiveness analysis UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=15636292http://www.journals.uchicago.edu/doi/pdf/10.1086/502343http://www.jstor.org/stable/pdfplus/10.1086/502343.pdf?acceptTC=true VL - 25 ID - 2457 ER - TY - JOUR AB - BACKGROUND: We hypothesized that investments to improve the control of tuberculosis in selected high-incidence countries would prove to be cost saving for the United States by reducing the incidence of the disease among migrants. METHODS: Using decision analysis, we estimated tuberculosis-related morbidity, mortality, and costs among legal immigrants and refugees, undocumented migrants, and temporary visitors from Mexico after their entry into the United States. We assessed the current strategy of radiographic screening of legal immigrants plus current tuberculosis-control programs alone and with the addition of either U.S.-funded expansion of the strategy of directly observed treatment, short course (DOTS), in Mexico or tuberculin skin testing to screen legal immigrants from Mexico. We also examined tuberculosis-related outcomes among migrants from Haiti and the Dominican Republic using the same three strategies. RESULTS: As compared with the current strategy, expanding the DOTS program in Mexico at a cost to the United States of 34.9 million dollars would result in 2591 fewer cases of tuberculosis in the United States, with 349 fewer deaths from the disease and net discounted savings of 108 million dollars over a 20-year period. Adding tuberculin skin testing to radiographic screening of legal immigrants from Mexico would result in 401 fewer cases of tuberculosis in the United States but would cost an additional 329 million dollars. Expansion of the DOTS program would remain cost saving even if the initial investment were doubled, if the United States paid for all antituberculosis drugs in Mexico, or if the decline in the incidence of tuberculosis in Mexico was less than projected. A 9.4 million dollars investment to expand the DOTS program in Haiti and the Dominican Republic would result in net U.S. savings of 20 million dollars over a 20-year period. CONCLUSIONS: U.S.-funded efforts to expand the DOTS program in Mexico, Haiti, and the Dominican Republic could reduce tuberculosis-related morbidity and mortality among migrants to the United States, producing net cost savings for the United States. AD - Respiratory Epidemiology Unit, Montreal Chest Institute, McGill University, Montreal, QC, Canada. AN - 16148286 AU - Schwartzman, K. AU - Oxlade, O. AU - Barr, R. G. AU - Grimard, F. AU - Acosta, I. AU - Baez, J. AU - Ferreira, E. AU - Melgen, R. E. AU - Morose, W. AU - Salgado, A. C. AU - Jacquet, V. AU - Maloney, S. AU - Laserson, K. AU - Mendez, A. P. AU - Menzies, D. DA - Sep 8 DO - 353/10/1008 [pii] 10.1056/NEJMsa043194 [doi] DP - Nlm ET - 09/09 KW - Antitubercular Agents/economics/therapeutic use Cost Savings Decision Support Techniques Directly Observed Therapy/ economics Dominican Republic Emigration and Immigration Haiti Health Care Costs Humans Incidence International Cooperation Investments Lung/ radiography Markov Chains Mass Screening Mexico/epidemiology Models, Economic Radiography, Thoracic/economics Tuberculin Test/ economics Tuberculosis, Pulmonary/diagnosis/economics/mortality/ prevention & control United States/epidemiology LA - eng N1 - Schwartzman, Kevin Oxlade, Olivia Barr, R Graham Grimard, Franque Acosta, Ivelisse Baez, Jeannette Ferreira, Elizabeth Melgen, Ricardo Elias Morose, Willy Salgado, Arturo Cruz Jacquet, Vary Maloney, Susan Laserson, Kayla Mendez, Ariel Pablos Menzies, Dick Comparative Study Research Support, Non-U.S. Gov't United States The New England journal of medicine N Engl J Med. 2005 Sep 8;353(10):1008-20. PY - 2005 RN - fulltext fulltext_1208 SN - 1533-4406 (Electronic) 0028-4793 (Linking) SP - 1008-20 ST - Domestic returns from investment in the control of tuberculosis in other countries T2 - N Engl J Med TI - Domestic returns from investment in the control of tuberculosis in other countries UR - http://www.nejm.org/doi/pdf/10.1056/NEJMsa043194 VL - 353 ID - 2468 ER - TY - JOUR AB - Mathematical models are formulated to establish the conditions (restrictions) on the size of the area occupied required minimizing and thereafter eradicating tuberculosis. Both numerical and qualitative analyses of the model are done and the effect of variation in the area size and recruitment rate on the different epidemiological groups is investigated. The results of the analysis show that there exists a stable disease-free equilibrium point provided that the characteristic area is greater than the product of the probability of survival from the latent stage to the infectious stage and the number of latent infections produced by a typical infectious individual during his/her mean infectious period. The study recommends that the characteristic area per individual should be at least 0.25 square kilometres in order to minimize the tuberculosis incidence. AU - Ssematimba, A. AU - Mugisha, J. Y. T. AU - Luboobi, L. S. DO - 10.3844/jmssp.2005.217.224 IS - 3 PY - 2005 SP - 217-224 ST - Mathematical Model Mathematical Models for the Dynamics of Tuberculosis in Density-dependent Populations: The Case of Internally Displaced Peoples' Camps (IDPCs) in Uganda T2 - Journal of Mathematics and Statistics TI - Mathematical Model Mathematical Models for the Dynamics of Tuberculosis in Density-dependent Populations: The Case of Internally Displaced Peoples' Camps (IDPCs) in Uganda VL - 1 ID - 4934 ER - TY - JOUR AB - Epidemics of HIV/AIDS have increased the tuberculosis (TB) case-load by five or more times in East Africa and southern Africa. As HIV continues to spread, warnings have been issued of disastrous AIDS and TB epidemics in "new-wave" countries, including India, which accounts for 20% of all new TB cases arising in the world each year. Here we investigate whether, in the face of the HIV epidemic, India's Revised National TB Control Program (RNTCP) could halve TB prevalence and death rates in the period 1990-2015, as specified by the United Nations Millennium Development Goals. Using a mathematical model to capture the spatial and temporal variation in TB and HIV in India, we predict that, without the RNTCP, HIV would increase TB prevalence (by 1%), incidence (by 12%), and mortality rates (by 33%) between 1990 and 2015. With the RNTCP, however, we expect substantial reductions in prevalence (by 68%), incidence (by 41%), and mortality (by 39%) between 1990 and 2015. In India, 29% of adults but 72% of HIV-positive adults live in four large states in the south where, even with the RNTCP, mortality is expected to fall by only 15% between 1990 and 2015. Nationally, the RNTCP should be able to reverse the increases in TB burden due to HIV but, to ensure that TB mortality is reduced by 50% or more by 2015, HIV-infected TB patients should be provided with antiretroviral therapy in addition to the recommended treatment for TB. AD - World Health Organization, 20 Avenue Appia, Geneva 1212, Switzerland. AN - 15976029 AU - Williams, B. G. AU - Granich, R. AU - Chauhan, L. S. AU - Dharmshaktu, N. S. AU - Dye, C. DA - Jul 5 DO - 0501615102 [pii] 10.1073/pnas.0501615102 [doi] DP - Nlm ET - 06/25 KW - AIDS-Related Opportunistic Infections/ epidemiology Communicable Disease Control/ methods Demography Developing Countries Forecasting Hiv Humans Incidence India/epidemiology Models, Theoretical Prevalence Public Health Tuberculosis/ epidemiology/mortality/ prevention & control/transmission LA - eng N1 - Williams, B G Granich, R Chauhan, L S Dharmshaktu, N S Dye, C Comparative Study United States Proceedings of the National Academy of Sciences of the United States of America Proc Natl Acad Sci U S A. 2005 Jul 5;102(27):9619-24. Epub 2005 Jun 23. PY - 2005 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 0027-8424 (Print) 0027-8424 (Linking) SP - 9619-24 ST - The impact of HIV/AIDS on the control of tuberculosis in India T2 - Proc Natl Acad Sci U S A TI - The impact of HIV/AIDS on the control of tuberculosis in India UR - http://www.pnas.org/content/102/27/9619.full.pdf VL - 102 ID - 2469 ER - TY - JOUR AB - In Eastern Europe and Central Asia (ECA) the control of tuberculosis, multidrug resistant tuberculosis (MDRTB) and human immunodeficiency virus (HIV) poses important public health challenges. We used system dynamics simulation to determine impact on cumulative HIV/AIDS, tuberculosis and HIV-associated-tuberculosis deaths, over 20 years, of harm-reduction programmes to reduce needle-sharing and injection-frequency amongst injecting drug users (IDUs) and multidrug resistant tuberculosis (MDRTB) control in a population with an explosive HIV epidemic in IDUs and high MDRTB prevalence. We estimate that the number of HIV-associated-deaths will decline by 30% with effective harm-reduction programmes but double if these are ineffective. In our model, effective MDRTB and HIV control reduces cumulative tuberculosis deaths by 54%, cumulative MDRTB deaths 15-fold and cumulative HIV-associated-tuberculosis-deaths 2-fold. Effective MDRTB control, without effective harm-reduction programmes, only reduce tuberculosis deaths by 22%. However, effective harm-reduction programme with a poor MDRTB control reduce cumulative tuberculosis deaths by 34%, MDRTB by 14% and HIV-associated-tuberculosis by 56%. Even with good control programmes for drug sensitive TB, neglecting harm reduction and MDRTB control will result in 50% more tuberculosis-related deaths than if both are effectively addressed. Effective harm-reduction programmes reduces cumulative deaths from tuberculosis more substantively than effective MDRTB control. Our finding have important policy implications for communicable disease policies in post-Soviet countries, which need to substantially change if they are to effectively address the emerging HIV and MDRTB epidemics. AD - Centre for Health Management, Tanaka Business School, Imperial College London, South Kensington Campus, London SW7 2AZ, UK. r.atun@imperial.ac.uk AN - 16854499 AU - Atun, R. A. AU - Lebcir, R. M. AU - McKee, M. AU - Habicht, J. AU - Coker, R. J. DA - May DO - S0168-8510(06)00131-X [pii] 10.1016/j.healthpol.2006.05.021 [doi] DP - Nlm ET - 07/21 KW - Antitubercular Agents Communicable Disease Control/methods Drug Resistance, Multiple Estonia/epidemiology HIV Infections/mortality Harm Reduction Health Policy Humans Models, Theoretical Tuberculosis/ drug therapy/mortality/prevention & control L1 - internal-pdf://1028025318/1-s2.0-S016885100600131X-main.pdf LA - eng N1 - Atun, Rifat A Lebcir, Reda M McKee, Martin Habicht, Jarno Coker, Richard J Ireland Health policy (Amsterdam, Netherlands) Health Policy. 2007 May;81(2-3):207-17. Epub 2006 Jul 18. PY - 2006 RN - fulltext fulltext_1208 SN - 0168-8510 (Print) 0168-8510 (Linking) SP - 207-17 ST - Impact of joined-up HIV harm reduction and multidrug resistant tuberculosis control programmes in Estonia: System dynamics simulation model T2 - Health Policy TI - Impact of joined-up HIV harm reduction and multidrug resistant tuberculosis control programmes in Estonia: System dynamics simulation model UR - http://ac.els-cdn.com/S016885100600131X/1-s2.0-S016885100600131X-main.pdf?_tid=d83372b2-f0e6-11e1-8283-00000aab0f6b&acdnat=1346141185_688289afe364cf51bd4bcc42a92c9b70 VL - 81 ID - 2495 ER - TY - BOOK A2 - Kolchanov, N. A2 - Hofestadt, R. AB - Motivation: A mathematical model to describe the immune response and different chemotherapeutic regimens for the treatment of tuberculosis (TB) has been developed. The model can be used as a tool for predicting the course of the infectious process and outcomes in individuals infected with Mycobacterium tuberculosis (MBT). To identify what chemotherapeutic regimen is the best, one should clearly understand how different anti-TB drugs work. One of the most promising approaches to elaborate optimal anti-TB chemotherapeutic treatment/regimen is the gene-network technology. Results: The model proposed herein consists of a set of ordinary differential equations for the dynamics of diverse populations of bacteria, macrophages, T lymphocytes, dendrite cells as well as for various concentrations of cytokines and antibacterial drugs. Different treatment regimens in individuals with different variants of the course of disease (latent and acute infection) were simulated, and so were different rates of drug inactivation (rapid and slow acetylators). Different regimes of the model, which yield different outcomes, correspond to different chemotherapeutic regimens, which either give recovery (adequate chemotherapy) or delay recovery and contribute to the emergence of drug-resistant strains (inadequate chemotherapy). A further progression of the model will be connected with optimization of the treatment regimens for TB. To serve the purpose, we have reconstructed the gene network for the mechanisms of anti-TB drugs and for the mechanisms underlying the emergence of drug resistance developed by MBT due to mutation in separate target genes. AD - SRC VB Vector, Novosibirsk 633159, Russia. Bazhan, SI (reprint author), SRC VB Vector, Novosibirsk 633159, Russia. AN - WOS:000243858000020 AU - Bazhan, S. I. AU - Schwartz, Y. S. AU - Gainova, I. A. AU - Ananko, E. A. CY - Novosibirsk KW - mathematical model mycobacteria tuberculosis infection immune response treatment regimens LA - English N1 - ISI Document Delivery No.: BFQ57 Times Cited: 0 Cited Reference Count: 3 Bazhan, S., I Schwartz, Ya. Sh Gainova, I. A. Ananko, E. A. Proceedings Paper 5th International Conference on Bioinformatics of Genome Regulation and Structure Jul 16-22, 2006 Novosibirsk, RUSSIA Inst Cytol & Genet, Lab Theoret Genet, Inst Cytol & Genet, Siberian Branch Russian Acad Sci, Vavilov Soc Genet & Breeders, Russian Acad Sci, Sci Council Bioinformat, Siberian Branch, Russian Acad Sci, Siberian Branch, Novosibirsk State Univ, Dept Natl Sci, Chair Informat Biol Novoskibrisk 90, morskoi, prosp 2, 630090 novosibirsk, russia PB - Russian Acad Sci Siberian Branch PY - 2006 SN - 978-5-7692-0847-8 SP - 114-117 ST - A mathematical model of immune response in infection induced by Mycobacteria tuberculosis. Prediction of the disease course and outcomes at different treatment regimens T2 - Proceedings of the Fifth International Conference on Bioinformatics of Genome Regulation and Structure, Vol 2 TI - A mathematical model of immune response in infection induced by Mycobacteria tuberculosis. Prediction of the disease course and outcomes at different treatment regimens UR - ://WOS:000243858000020 ID - 6142 ER - TY - JOUR AB - OBJECTIVE: Newborns in a hospital nursery were exposed to a mother whose sputum was direct-smear negative for acid-fast bacilli but culture positive for Mycobacterium tuberculosis. Given the low risk for exposure, the high susceptibility of infants to M. tuberculosis infection, and the possibility of hepatotoxicity due to isoniazid therapy, a decision analysis model was used to determine whether administration of isoniazid prophylaxis against tuberculosis is preferable to no administration of prophylaxis. DESIGN: A decision analysis tree was constructed with software, using probabilities from the literature and costs from local health facilities. The expected values for each strategy were obtained, and sensitivity analyses were performed. RESULTS: For the strategy in which prophylaxis was administered under direct observation (DO), the probability for survival was 0.999980. For the strategy in which no prophylaxis was administered, the probability of survival was 0.999950, which corresponds to 3 more deaths per 100,000 patients than with the DO prophylaxis strategy. The incremental cost-effectiveness of the DO prophylaxis strategy was 21,710,000 US dollars per death prevented. Sensitivity analysis for survival showed that the DO prophylaxis strategy was preferable to the strategy in which no prophylaxis is given if the probability of infection was >0.0002, the probability of tuberculous disease in an infected infant who did not receive prophylaxis was greater than 0.12, the probability of dying from tuberculosis was greater than 0.025, the probability of hepatotoxicity was less than 0.004, and the probability of dying from hepatotoxicity was less than 0.04. For the strategy in which prophylaxis was administered under non-DO conditions (ie, by parents), the incremental cost-effectiveness was 929,500 US dollars per death prevented, which is approximately 5% of the incremental cost-effectiveness of the DO prophylaxis strategy. CONCLUSION: This model provides a structure for determining the preferable prophylaxis strategies for different risks of exposure to tuberculosis in a nursery. Administration of prophylaxis is preferable to no administration of prophylaxis, unless the probability of infection is extremely low. AD - Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30303, USA. fberkow@emory.edu AN - 16755481 AU - Berkowitz, F. E. AU - Severens, J. L. AU - Blumberg, H. M. DA - Jun DO - 10.1086/504359 DP - Nlm ET - 06/07 J2 - Infection control and hospital epidemiology : the official journal of the Society of Hospital Epidemiologists of America KW - Acquired Immunodeficiency Syndrome/complications Antibiotic Prophylaxis Antitubercular Agents/adverse effects/ therapeutic use Decision Support Techniques Decision Trees Disease Transmission, Infectious Drug Toxicity/chemically induced Humans Infant, Newborn Isoniazid/adverse effects/ therapeutic use Models, Biological Survival Analysis Tuberculosis/complications/ prevention & control/transmission LA - eng N1 - Berkowitz, Frank E Severens, Johan L Blumberg, Henry M United States Infect Control Hosp Epidemiol. 2006 Jun;27(6):604-11. Epub 2006 May 31. PY - 2006 RN - fulltext fulltext_1208 SN - 0899-823X (Print) 0899-823X (Linking) SP - 604-11 ST - Exposure to tuberculosis among newborns in a nursery: decision analysis for initiation of prophylaxis T2 - Infect Control Hosp Epidemiol TI - Exposure to tuberculosis among newborns in a nursery: decision analysis for initiation of prophylaxis UR - http://www.jstor.org/stable/pdfplus/10.1086/504359.pdf?acceptTC=true VL - 27 ID - 2471 ER - TY - JOUR AN - 17356 AU - Clark, M. AU - Cameron, D. W. KW - BCG complications disseminated extrapulmonary HIV immunodeficiency infants models tuberculosis vaccination N1 - IN FILE TB Intervention strategies BCG vaccination Safety BCG - complications PY - 2006 RN - fulltext fulltext_1208 SP - 1-12 ST - The benefits and risks of bacille Calmette-Gu‚rin vaccination among infants at high risk for both tuberculosis and severe combined immunodeficiency: assessment by Markov model T2 - BMC Pediatrics TI - The benefits and risks of bacille Calmette-Gu‚rin vaccination among infants at high risk for both tuberculosis and severe combined immunodeficiency: assessment by Markov model UR - file://C:\literature_pdf\rm17356.pdf VL - 6-5 ID - 2472 ER - TY - JOUR AB - In sub-Saharan Africa, where the emergence of HIV has caused dramatic increases in tuberculosis (TB) case notifications, new strategies for TB control are necessary. Isoniazid preventive therapy (IPT) for HIV-TB coinfected individuals reduces the reactivation of latent Mycobacterium tuberculosis infections and is being evaluated as a potential community-wide strategy for improving TB control. We developed a mathematical model of TB/HIV coepidemics to examine the impact of community-wide implementation of IPT for TB-HIV coinfected individuals on the dynamics of drug-sensitive and -resistant TB epidemics. We found that community-wide IPT will reduce the incidence of TB in the short-term but may also speed the emergence of drug-resistant TB. We conclude that community-wide IPT in areas of emerging HIV and drug-resistant TB should be coupled with diagnostic and treatment policies designed to identify and effectively treat the increasing proportion of patients with drug-resistant TB. AD - Division of Social Medicine and Health Inequalities, Brigham and Women's Hospital, One Brigham Circle, 1620 Tremont Street, Boston, MA 02120, USA. tcohen@hsph.harvard.edu AN - 16632605 AU - Cohen, T. AU - Lipsitch, M. AU - Walensky, R. P. AU - Murray, M. DA - May 2 DO - 0600349103 [pii] 10.1073/pnas.0600349103 [doi] DP - Nlm ET - 04/25 KW - AIDS-Related Opportunistic Infections/drug therapy/epidemiology/prevention & control Africa South of the Sahara/epidemiology Antitubercular Agents/ therapeutic use Comorbidity HIV Infections/complications/epidemiology Humans Isoniazid/ therapeutic use Models, Theoretical Tuberculosis, Multidrug-Resistant/drug therapy/epidemiology/etiology/prevention & control L1 - internal-pdf://3299365905/Cohen-2006-Beneficial and perverse effects of.pdf LA - eng N1 - Cohen, Ted Lipsitch, Marc Walensky, Rochelle P Murray, Megan 1R21 AI55825-01/AI/NIAID NIH HHS/United States K08 AI055985/AI/NIAID NIH HHS/United States K08 AI055985-04/AI/NIAID NIH HHS/United States K23 AI01794-05/AI/NIAID NIH HHS/United States T32 AI007433-10/AI/NIAID NIH HHS/United States Research Support, N.I.H., Extramural United States Proceedings of the National Academy of Sciences of the United States of America Proc Natl Acad Sci U S A. 2006 May 2;103(18):7042-7. Epub 2006 Apr 21. PY - 2006 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 0027-8424 (Print) 0027-8424 (Linking) SP - 7042-7 ST - Beneficial and perverse effects of isoniazid preventive therapy for latent tuberculosis infection in HIV-tuberculosis coinfected populations T2 - Proc Natl Acad Sci U S A TI - Beneficial and perverse effects of isoniazid preventive therapy for latent tuberculosis infection in HIV-tuberculosis coinfected populations UR - http://www.pnas.org/content/103/18/7042.full.pdf https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1459015/pdf/zpq7042.pdf VL - 103 ID - 2473 ER - TY - JOUR AB - SETTING: Various methods have been used to estimate the prevalence of Mycobacterium tuberculosis infection from tuberculin survey data. All are complicated by prior sensitisation to environmental mycobacteria and bacille Calmette-Guerin (BCG) vaccination. Mixture analysis has recently been proposed as a means of overcoming misclassification and improving infection prevalence estimates. OBJECTIVE: To compare conventional and mixture model estimates of M. tuberculosis infection prevalence. DESIGN: Mixture models with two or three univariate normal components were fitted to the results of 53 909 tuberculin tests conducted in northern Malawi during 1980-1984. Data were stratified by BCG status, sex and age and corrected for digit preference. Prevalence estimates derived from mixture models were compared with those of conventional methods. RESULTS: The optimal model was age-dependent, with three- and one-component solutions preferred in younger and older age groups, respectively. In contrast with findings from elsewhere, a component corresponding to BCG vaccination was indistinguishable from that attributable to environmental mycobacterial exposure, and infection prevalence estimates in younger individuals with a BCG scar were inflated, irrespective of the method used. CONCLUSION: The validity of infection prevalence and incidence estimates based on mixture modelling is probably locale-dependent, and the assumptions underlying mixture models may not realistically reflect underlying immunological processes. AD - Department of Pharmacology, University of Liverpool, Liverpool, Merseyside, United Kingdom. gerrydavies@doctors.org.uk AN - 16964795 AU - Davies, G. R. AU - Fine, P. E. AU - Vynnycky, E. DA - Sep DP - Nlm ET - 09/13 KW - Adolescent Adult Aged Child Female Humans Malawi/epidemiology Male Middle Aged Prevalence Questionnaires Tuberculin Test/methods/ statistics & numerical data Tuberculosis/ diagnosis/ epidemiology LA - eng N1 - Davies, G R Fine, P E Vynnycky, E 079828/Wellcome Trust/United Kingdom Wellcome Trust/United Kingdom Research Support, Non-U.S. Gov't France The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease Int J Tuberc Lung Dis. 2006 Sep;10(9):1023-9. PY - 2006 RN - fulltext fulltext_1208 SN - 1027-3719 (Print) 1027-3719 (Linking) SP - 1023-9 ST - Mixture analysis of tuberculin survey data from northern Malawi and critique of the method T2 - Int J Tuberc Lung Dis TI - Mixture analysis of tuberculin survey data from northern Malawi and critique of the method VL - 10 ID - 2474 ER - TY - JOUR AB - OBJECTIVES: To evaluate whether methodological optimization of serial sputum colony counting (SSCC) studies, a potentially important component in the drug development process for tuberculosis, could significantly improve their power. METHODS: Simulations were carried out using a model derived from a large SSCC dataset. Variance inflation factors (VIFs) were calculated for model parameters, focusing on the elimination rate constant likely to reflect 'sterilizing' activity and sampling schemes were optimized relative to a scheme of daily sampling during the initial phase of therapy. Corresponding sample sizes required for SSCC studies using different schemes were also computed. RESULTS: Published sampling schemes lacked efficiency with respect to the 'sterilizing' phase. Pragmatic optimized schemes yielding greatest precision were achieved using eleven sampling points around a skeleton of 0, 2, 7, 14 and 56 days. The standard error of the 'sterilizing' rate constant was reduced more than 4-fold, and sample size for realistic treatment effects was effectively halved. Even schemes with a restricted duration of sampling to avoid high proportions of missing data and those with fewer sampling points still achieved significant gains in precision. Sensitivity analysis suggested that such schemes should continue to perform well over the immediately foreseeable range of improvements in therapy. CONCLUSIONS: Methodological improvements in the design of SSCC studies could make them a powerful tool in Phase II development of anti-tuberculosis agents. AD - Wellcome Trust Centre for Clinical Tropical Medicine, University of Liverpool, Merseyside, UK. gdavies@doctors.org.uk AN - 16857690 AU - Davies, G. R. AU - Khoo, S. H. AU - Aarons, L. J. DA - Sep DO - dkl272 [pii] 10.1093/jac/dkl272 [doi] DP - Nlm ET - 07/22 KW - Antitubercular Agents/administration & dosage/ pharmacology/therapeutic use Colony Count, Microbial Computer Simulation Humans Models, Biological Predictive Value of Tests Sample Size Specimen Handling/methods/standards Sputum/ microbiology Tuberculosis, Pulmonary/drug therapy/ microbiology LA - eng N1 - Davies, G R Khoo, S H Aarons, L J GR067910MA/Wellcome Trust/United Kingdom Research Support, Non-U.S. Gov't England The Journal of antimicrobial chemotherapy J Antimicrob Chemother. 2006 Sep;58(3):594-600. Epub 2006 Jul 19. PY - 2006 RN - fulltext fulltext_1208 SN - 0305-7453 (Print) 0305-7453 (Linking) SP - 594-600 ST - Optimal sampling strategies for early pharmacodynamic measures in tuberculosis T2 - J Antimicrob Chemother TI - Optimal sampling strategies for early pharmacodynamic measures in tuberculosis UR - http://jac.oxfordjournals.org/content/58/3/594.full.pdf VL - 58 ID - 2475 ER - TY - JOUR AN - 15908 AU - Diel, R. AU - Nienhaus, A. AU - Lange, C. AU - Schaberg, T. KW - case-finding contacts costs epidemiology infection screening tuberculosis N1 - TB Tuberculosis control Case-finding No sub-heading PY - 2006 RN - fulltext fulltext_1208 SP - 35-44 ST - Cost-optimisation of screening for latent tuberculosis in close contacts T2 - Eur.Respir.J. TI - Cost-optimisation of screening for latent tuberculosis in close contacts UR - file://C:\literature_pdf\rm15908.pdf VL - 28 ID - 2476 ER - TY - JOUR AB - OBJECTIVE: To explore the potential impact of enhanced tuberculosis (TB) diagnostic techniques as a TB control strategy in an adult population with high HIV prevalence. DESIGN: A compartmental difference-equation model of TB/HIV was developed using parameter estimates from the literature. METHODS: The impact of five TB control interventions (rapid molecular testing, mycobacterial culture, community-wide and HIV-targeted active case finding, and highly active antiretroviral therapy) on TB incidence, prevalence, and mortality was modeled in a steady-state population with an HIV prevalence of 17% and annual TB incidence of 409 per 100 000. Sensitivity analyses assessed the influence of each model parameter on the interventions' mortality impact. RESULTS: Enhanced diagnostic techniques (rapid molecular testing or culture) are each projected to reduce TB prevalence and mortality by 20% or more, an impact similar to that of active case-finding in 33% of the general community and greater than the effect achievable by case-finding or antiretroviral treatment efforts in HIV-positive patients alone. The projected impact of enhanced diagnostics on TB incidence (< 10% reduction) is smaller. The impact of TB diagnostics is sensitive to the quality of existing diagnostic standards and the level of access to diagnostic services, but is robust across a wide range of population parameters including HIV and TB incidence. CONCLUSIONS: Enhanced TB diagnostic techniques may have substantial impact on TB morbidity and mortality in HIV-endemic regions. As TB rates continue to increase in these areas, enhanced diagnostic techniques merit further consideration as TB control strategies. AD - Department of Epidemiology, Johns Hopkins University, Baltimore, Maryland 21231, USA. AN - 16514306 AU - Dowdy, D. W. AU - Chaisson, R. E. AU - Moulton, L. H. AU - Dorman, S. E. DA - Mar 21 DO - 10.1097/01.aids.0000216376.07185.cc [doi] 00002030-200603210-00015 [pii] DP - Nlm ET - 03/04 KW - AIDS-Related Opportunistic Infections/ diagnosis Adolescent Adult Anti-HIV Agents/therapeutic use Antiretroviral Therapy, Highly Active Bacterial Typing Techniques Communicable Disease Control DNA, Bacterial/analysis Developing Countries Disease Outbreaks HIV Infections/ complications/drug therapy Health Services Accessibility Humans Incidence Intervention Studies Middle Aged Models, Statistical Mycobacterium tuberculosis/genetics/isolation & purification Prevalence Tuberculosis/ diagnosis/epidemiology/virology LA - eng N1 - Dowdy, David W Chaisson, Richard E Moulton, Lawrence H Dorman, Susan E 5 T32 GMO7309/PHS HHS/United States K23 AI 51528/AI/NIAID NIH HHS/United States K24 AI16137/AI/NIAID NIH HHS/United States Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't England AIDS (London, England) AIDS. 2006 Mar 21;20(5):751-62. PY - 2006 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 0269-9370 (Print) 0269-9370 (Linking) SP - 751-62 ST - The potential impact of enhanced diagnostic techniques for tuberculosis driven by HIV: a mathematical model T2 - AIDS TI - The potential impact of enhanced diagnostic techniques for tuberculosis driven by HIV: a mathematical model UR - http://graphics.tx.ovid.com/ovftpdfs/FPDDNCDCLFEDDD00/fs047/ovft/live/gv024/00002030/00002030-200603210-00015.pdf VL - 20 ID - 2477 ER - TY - JOUR AB - Antibiotic resistance is seen in both the hospital and community settings. Approaches are required to minimize the increase in resistant strains, such as good antibiotic stewardship and the limiting of antibiotic use to appropriate circumstances. There are instances when drug dose and/or schedule can be used to minimize the probability that mutants will take over the bacterial population. Over the past several years, significant advances have been made in understanding the relationship between drug concentrations and amplification of resistant mutant subpopulations. In this review, we examine the use of preclinical models for facilitating this understanding. We also use mathematical techniques, including Monte Carlo simulation, to bridge between the identification of exposures to minimize resistance and the examination of candidate drug doses to achieve this end. Examples are provided for Pseudomonas aeruginosa, Streptococcus pneumoniae, Staphylococcus aureus, and Mycobacterium tuberculosis. In each instance, quinolone antimicrobials were examined. More investigations with other pathogens and drug classes are required. AD - Ordway Research Institute, Albany, NY 12208, USA. gdrusano@ordwayresearch.org AN - 16421797 AU - Drusano, G. L. AU - Louie, A. AU - Deziel, M. AU - Gumbo, T. DA - Feb 15 DO - CID36544 [pii] 10.1086/499046 [doi] DP - Nlm ET - 01/20 KW - Animals Anti-Infective Agents/pharmacokinetics/ pharmacology Bacterial Infections/ drug therapy Colony Count, Microbial Dose-Response Relationship, Drug Drug Resistance, Bacterial/ drug effects/ physiology Humans Mice Microbial Sensitivity Tests Models, Biological Monte Carlo Method L1 - internal-pdf://1649502949/Drusano-2006-The crisis of resistance_ identif.pdf LA - eng N1 - Drusano, G L Louie, Arnold Deziel, Mark Gumbo, Tawanda Review United States Clinical infectious diseases : an official publication of the Infectious Diseases Society of America Clin Infect Dis. 2006 Feb 15;42(4):525-32. Epub 2006 Jan 3. PY - 2006 RN - fulltext fulltext_1208 SN - 1537-6591 (Electronic) 1058-4838 (Linking) SP - 525-32 ST - The crisis of resistance: identifying drug exposures to suppress amplification of resistant mutant subpopulations T2 - Clin Infect Dis TI - The crisis of resistance: identifying drug exposures to suppress amplification of resistant mutant subpopulations UR - http://cid.oxfordjournals.org/content/42/4/525.full.pdf https://watermark.silverchair.com/42-4-525.pdf?token=AQECAHi208BE49Ooan9kkhW_Ercy7Dm3ZL_9Cf3qfKAc485ysgAAAcowggHGBgkqhkiG9w0BBwagggG3MIIBswIBADCCAawGCSqGSIb3DQEHATAeBglghkgBZQMEAS4wEQQMBJH3goF9hSba_DMrAgEQgIIBfXW1oY85-GXNdbaieNT-FJ0EXj2erYGCTn7r2oOktrJiSTcG_4c-BW0O9xyOM4PmhCwEDrQyAk4URyJglfIhG1W5qSmUn3qQyERy1hF8-7HPDcos8PVRWln8F0ZsdR0wR3IdscsA3yQk904B_FOgxSPlKOLOHr93vqC7t1Gmlk7m1WTyNqZZiS69tf_v7zKIOhH5YldUCWqj5gBwfSvf6svFqmlnPEJSCikJWGw97XLUbL8mLza1VCdoOjqNoVoS-NQ7gf3FIBhzHlxM9MnEDlNBF6qrtHsbstBercot4kpKrNLXCUN7auTKVTmUESA0vl8ArfjUuvB3YzSIsidf9MallbFogkrNkNEpRxJd2Ljjw3uixGZ3vNa-iklAy4KGahZuNGWCdJl9wbH7iPZRfOGR67hkzO8v4DU2WZVj8ogbF27EhMmMT0Es6v2L_6YfAw6ZE_gTQtnJ8Dw8iJL1LRYpTW-OT8g6aoX61xt5kz7x_pHO8EDEKcgvNfK0gQ VL - 42 ID - 2478 ER - TY - CPAPER AU - Hughes, Georgina R. AU - Currie, Christine S. M. AU - Corbett, Elizabeth L. C1 - 1218200 CY - Monterey, California PB - Winter Simulation Conference PY - 2006 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SP - 459-465 T2 - Proceedings of the 38th conference on Winter simulation TI - Modeling tuberculosis in areas of high HIV prevalence UR - http://dl.acm.org/citation.cfm?id=1218200 ID - 2479 ER - TY - JOUR AB - BACKGROUND: Implementation of the World Health Organization's DOTS strategy (Directly Observed Treatment Short-course therapy) can result in significant reduction in tuberculosis incidence. We estimated potential costs and benefits of DOTS expansion in Haiti from the government, and societal perspectives. METHODS: Using decision analysis incorporating multiple Markov processes (Markov modelling), we compared expected tuberculosis morbidity, mortality and costs in Haiti with DOTS expansion to reach all of the country, and achieve WHO benchmarks, or if the current situation did not change. Probabilities of tuberculosis related outcomes were derived from the published literature. Government health expenditures, patient and family costs were measured in direct surveys in Haiti and expressed in 2003 US$. RESULTS: Starting in 2003, DOTS expansion in Haiti is anticipated to cost $4.2 million and result in 63,080 fewer tuberculosis cases, 53,120 fewer tuberculosis deaths, and net societal savings of $131 million, over 20 years. Current government spending for tuberculosis is high, relative to the per capita income, and would be only slightly lower with DOTS. Societal savings would begin within 4 years, and would be substantial in all scenarios considered, including higher HIV seroprevalence or drug resistance, unchanged incidence following DOTS expansion, or doubling of initial and ongoing costs for DOTS expansion. CONCLUSION: A modest investment for DOTS expansion in Haiti would provide considerable humanitarian benefit by reducing tuberculosis-related morbidity, mortality and costs for patients and their families. These benefits, together with projected minimal Haitian government savings, argue strongly for donor support for DOTS expansion. AD - National tuberculosis control programme, Port-au-Prince, Haiti. varyj@yahoo.com AN - 16911786 AU - Jacquet, V. AU - Morose, W. AU - Schwartzman, K. AU - Oxlade, O. AU - Barr, G. AU - Grimard, F. AU - Menzies, D. DO - 1471-2458-6-209 [pii] 10.1186/1471-2458-6-209 [doi] DP - Nlm ET - 08/17 KW - Antitubercular Agents/ administration & dosage/economics Cost of Illness Directly Observed Therapy/ economics Drug Therapy, Combination Ethambutol/administration & dosage/economics Haiti/epidemiology Health Care Costs Humans Isoniazid/administration & dosage/economics Program Evaluation Pyrazinamide/administration & dosage/economics Rifampin/administration & dosage/economics Treatment Outcome Tuberculosis, Pulmonary/ drug therapy/ economics/epidemiology World Health Organization L1 - internal-pdf://3904429895/Jacquet-2006-Impact of DOTS expansion on tuber.pdf LA - eng N1 - Jacquet, Vary Morose, Willy Schwartzman, Kevin Oxlade, Olivia Barr, Graham Grimard, Franque Menzies, Dick Evaluation Studies Research Support, Non-U.S. Gov't England BMC public health BMC Public Health. 2006 Aug 15;6:209. PY - 2006 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1471-2458 (Electronic) 1471-2458 (Linking) SP - 209 ST - Impact of DOTS expansion on tuberculosis related outcomes and costs in Haiti T2 - BMC Public Health TI - Impact of DOTS expansion on tuberculosis related outcomes and costs in Haiti UR - http://www.biomedcentral.com/1471-2458/6/209http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1590025/pdf/1471-2458-6-209.pdf https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1590025/pdf/1471-2458-6-209.pdf VL - 6 ID - 2480 ER - TY - JOUR AU - Joshi, Rajani R. AU - Raghuvanshi, Meenakshi AU - Pandya, Pranav DO - doi:10.1142/S0218339006001891 PY - 2006 RN - fulltext fulltext_1208 SP - 463-489 ST - YAGYOPATHY VERSUS ORAL AND IV DRUG ADMINISTRATION: EVALUATION FOR PULMONARY TUBERCULOSIS USING COMPARTMENT MODELING T2 - Journal of Biological Systems TI - YAGYOPATHY VERSUS ORAL AND IV DRUG ADMINISTRATION: EVALUATION FOR PULMONARY TUBERCULOSIS USING COMPARTMENT MODELING UR - http://www.worldscientific.com/doi/abs/10.1142/S0218339006001891 VL - 14 ID - 2481 ER - TY - JOUR AB - PURPOSE: Assess the costs and cost-effectiveness of an incentive-based tuberculosis (TB) program designed to promote adolescents' compliance with treatment for latent TB infection (LTBI). METHODS: Randomized controlled trial. Adolescents between the ages of 11 and 19 years who were referred to one of two participating clinics after being screened for TB and receiving a positive diagnosis indicating LTBI (n = 794) were assigned to one of four groups: usual care, peer counseling, contingency contracting, and combined peer counseling/contingency contracting. Primary outcome variables were completion of isoniazid preventive therapy (IPT), total treatment costs, and lifetime TB-related costs per quality-adjusted life year (QALY) in each of the four study groups (three treatment, one control). Cost effectiveness was evaluated using a five-stage Markov model and a Monte Carlo simulation with 10,000 trials. RESULTS: Average costs were 199 dollars for usual care (UC), 277 dollars for peer counseling (PC), 326 dollars for contingency contracting (CC), and 341 dollars for PC + CC combined. The differences among these groups were all significant at the p = .001 level. Only the PC + CC group improved the rate of IPT completion (83.8%) relative to usual care (75.9%) (p = .051), with an overall incremental CE ratio of 209 dollars per QALY relative to usual care. CONCLUSION: Incentives combined with peer counseling are a cost-effective strategy for helping adolescents to complete care when combined with peer counseling. AD - Department of Health Services, UCLA School of Public Health, Los Angeles, California 90024, USA. kominski@ucla.edu AN - 17185207 AU - Kominski, G. F. AU - Varon, S. F. AU - Morisky, D. E. AU - Malotte, C. K. AU - Ebin, V. J. AU - Coly, A. AU - Chiao, C. DA - Jan DO - 10.1016/j.jadohealth.2006.08.012 DP - Nlm ET - 12/23 J2 - The Journal of adolescent health : official publication of the Society for Adolescent Medicine KW - Adolescent Antitubercular Agents/therapeutic use Child Contracts Cost-Benefit Analysis Counseling/economics/ methods Female Health Care Costs Humans Isoniazid/therapeutic use Logistic Models Los Angeles Male Markov Chains Monte Carlo Method Motivation Patient Compliance/psychology Peer Group Quality-Adjusted Life Years Reward Tuberculosis/economics/ prevention & control LA - eng N1 - Kominski, Gerald F Varon, Sepideh Farivar Morisky, Donald E Malotte, C Kevin Ebin, Vicki J Coly, Astou Chiao, Chi R01-55770/PHS HHS/United States T32 HS00046/HS/AHRQ HHS/United States Multicenter Study Randomized Controlled Trial Research Support, N.I.H., Extramural Research Support, U.S. Gov't, P.H.S. United States J Adolesc Health. 2007 Jan;40(1):61-8. Epub 2006 Oct 27. PY - 2006 RN - fulltext fulltext_1208 SN - 1879-1972 (Electronic) 1054-139X (Linking) SP - 61-8 ST - Costs and cost-effectiveness of adolescent compliance with treatment for latent tuberculosis infection: results from a randomized trial T2 - J Adolesc Health TI - Costs and cost-effectiveness of adolescent compliance with treatment for latent tuberculosis infection: results from a randomized trial UR - http://ac.els-cdn.com/S1054139X06003089/1-s2.0-S1054139X06003089-main.pdf?_tid=90d79c56-f1d4-11e1-a0a1-00000aab0f01&acdnat=1346243286_cc1761d7767c3933366d4866b5dee7d3 VL - 40 ID - 2507 ER - TY - JOUR AB - This work elaborates on the effects of cytotoxic lymphocytes (CTLs) and other immune mechanisms in determining whether a TB-infected individual will develop active or latent TB. It answers one intriguing question: why do individuals infected with Mycobacterium tuberculosis (Mtb) experience different clinical outcomes? In addressing this question, we have developed a model that captures the effects of CTLs and the combined effects of CD4+ helper T cells (Th1 and Th2) immune response mechanisms to TB infection. The occurrence of active or latent infection is shown to depend on a number of factors that include effector function and levels of CTLs. We use the model to predict disease progression scenarios, including primary, latency or clearance. Model analysis shows that occurrence of active disease is much attributed to the Mtb pathogen ability to persist outside the intracellular environment and that high levels of CTLs result in latent TB, while low levels of CTLs result in active TB. This is attributed to the CTLs' ability to directly kill infected macrophages and the bacteria inside the infected macrophages. The study suggests directions for further basic studies and potential new treatment strategies. AD - Department of Applied Mathematics, National University of Science and Technology, PO Box AC939 Ascot, Bulawayo, Zimbabwe. gmagombedze@nust.ac.zw. AN - 20361838 AU - Magombedze, G. AU - Garira, W. AU - Mwenje, E. DA - Oct DP - Nlm ET - 10/01 LA - eng N1 - Magombedze, Gesham Garira, Winston Mwenje, Eddie United States Mathematical biosciences and engineering : MBE Math Biosci Eng. 2006 Oct;3(4):661-82. PY - 2006 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1547-1063 (Print) 1547-1063 (Linking) SP - 661-82 ST - Modelling the human immune response mechanisms to mycobacterium tuberculosis infection in the lungs T2 - Math Biosci Eng TI - Modelling the human immune response mechanisms to mycobacterium tuberculosis infection in the lungs VL - 3 ID - 2482 ER - TY - JOUR AU - Magombedze, Gesham AU - Garira, Winston AU - Mwenje, Eddie DO - doi:10.1142/S0218339006001945 PY - 2006 RN - fulltext fulltext_1208 SP - 509-553 ST - MATHEMATICAL MODELING OF CHEMOTHERAPY OF HUMAN TB INFECTION T2 - Journal of Biological Systems TI - MATHEMATICAL MODELING OF CHEMOTHERAPY OF HUMAN TB INFECTION UR - http://www.worldscientific.com/doi/abs/10.1142/S0218339006001945 VL - 14 ID - 2483 ER - TY - JOUR AB - The spread of tuberculosis is studied through two models which include fast and slow progression to the infected class. For each model, Lyapunov functions are used to show that when the basic reproduction number is less than or equal to one, the disease-free equilibrium is globally asymptotically stable, and when it is greater than one there is an endemic equilibrium which is globally asymptotically stable. AD - Department of Mathematics, Wilfrid Laurier University, 75 University Ave West, Waterloo, ON, N2L 3C5, Canada. cmccluskey@wlu.ca. AN - 20361835 AU - McCluskey, C. C. DA - Oct DP - Nlm ET - 10/01 LA - eng N1 - McCluskey, C Connell United States Mathematical biosciences and engineering : MBE Math Biosci Eng. 2006 Oct;3(4):603-14. PY - 2006 RN - fulltext fulltext_1208 SN - 1547-1063 (Print) 1547-1063 (Linking) SP - 603-14 ST - Lyapunov functions for tuberculosis models with fast and slow progression T2 - Math Biosci Eng TI - Lyapunov functions for tuberculosis models with fast and slow progression VL - 3 ID - 2484 ER - TY - JOUR AB - BACKGROUND: Between April 2001 and March 2004, the Directly Observed Therapy-Short course (DOTS) program was successfully implemented by the National Tuberculosis control program, with assistance from the Canadian Lung Association, in three provinces of Ecuador, where 52% of the population of the country reside. METHODS: Markov modelling was used to project TB-related morbidity, mortality and costs if the former TB control program (status quo) had continued or if the newly expanded DOTS program is maintained over 20 years. Extensive sensitivity analyses were used to determine the effect on projected outcomes of varying key assumptions. RESULTS: If DOTS is maintained over the next 20 years, we predict that 18,760 cases and 15,812 TB-related deaths will be prevented, resulting in societal savings of dollars 203 million and government savings of dollars 7.1 million (all costs in dollars US). These findings were robust in extensive sensitivity analyses. Given the initial investment of dollars 3 million for DOTS implementation, this would mean a cost of dollars 190 per life saved. CONCLUSIONS: Implementation of DOTS could yield very substantial public health and economic benefits for Ecuador. These results demonstrate the benefits from Canadian government support for DOTS implementation in low- and middle-income countries. AD - Respiratory Epidemiology & Clinical Research Unit, Montreal Chest Institute, McGill University, QC, Canada. AN - 16512320 AU - Oxlade, O. AU - Vaca, J. AU - Romero, E. AU - Schwartzman, K. AU - Graham, B. AU - Hernandez, L. AU - Tannenbaum, T. AU - Menzies, D. DA - Jan-Feb DP - Nlm ET - 03/04 KW - Canada Communicable Disease Control/ economics Cost Savings Cost of Illness Cost-Benefit Analysis Decision Support Techniques Directly Observed Therapy/ economics Ecuador/epidemiology Forecasting Humans Markov Chains Program Development Program Evaluation Quality-Adjusted Life Years Risk Assessment Time Factors Tuberculosis/ drug therapy/ economics/epidemiology/mortality LA - eng N1 - Oxlade, Olivia Vaca, Judyth Romero, Elizabeth Schwartzman, Kevin Graham, Brian Hernandez, Lucero Tannenbaum, Terry Menzies, Dick Evaluation Studies Research Support, Non-U.S. Gov't Canada Canadian journal of public health. Revue canadienne de sante publique Can J Public Health. 2006 Jan-Feb;97(1):14-9. PY - 2006 RN - fulltext fulltext_1208 SN - 0008-4263 (Print) 0008-4263 (Linking) SP - 14-9 ST - The long-term health and economic benefits of DOTS implementation in Ecuador T2 - Can J Public Health TI - The long-term health and economic benefits of DOTS implementation in Ecuador VL - 97 ID - 2485 ER - TY - JOUR AB - BACKGROUND: Immigrants to the U.S. are required to undergo overseas screening for tuberculosis (TB), but the value of evaluation and treatment following entry to the U.S. is not well understood. We determined the cost-effectiveness of domestic follow-up of immigrants identified as tuberculosis suspects through overseas screening. METHODS: Using a stochastic simulation for tuberculosis reactivation, transmission, and follow-up for a hypothetical cohort of 1000 individuals, we calculated the incremental cost-effectiveness of follow-up and evaluation interventions. We utilized published literature, California Reports of Verified Cases of Tuberculosis (RVCTs), demographic estimates from the California Department of Finance, Medicare reimbursement, and Medi-Cal reimbursement rates. Our target population was legal immigrants to the United States, our time horizon is twenty years, and our perspective was that of all domestic health-care payers. We examined the intervention to offer latent tuberculosis therapy to infected individuals, to increase the yield of domestic evaluation, and to increase the starting and completion rates of LTBI therapy with INH (isoniazid). Our outcome measures were the number of cases averted, the number of deaths averted, the incremental dollar cost (year 2004), and the number of quality-adjusted life-years saved. RESULTS: Domestic follow-up of B-notification patients, including LTBI treatment for latently infected individuals, is highly cost-effective, and at times, cost-saving. B-notification follow-up in California would reduce the number of new tuberculosis cases by about 6-26 per year (out of a total of approximately 3000). Sensitivity analysis revealed that domestic follow-up remains cost-effective when the hepatitis rates due to INH therapy are over fifteen times our best estimates, when at least 0.4 percent of patients have active disease and when hospitalization of cases detected through domestic follow-up is no less likely than hospitalization of passively detected cases. CONCLUSION: While the current immigration screening program is unlikely to result in a large change in case rates, domestic follow-up of B-notification patients, including LTBI treatment, is highly cost-effective. If as many as three percent of screened individuals have active TB, and early detection reduces the rate of hospitalization, net savings may be expected. AD - California Department of Health Services, Tuberculosis Control Branch, 850 Marina Bay Parkway, Building P, Second Floor, Richmond, CA 94804, USA. tporco@dhs.ca.gov AN - 16784541 AU - Porco, T. C. AU - Lewis, B. AU - Marseille, E. AU - Grinsdale, J. AU - Flood, J. M. AU - Royce, S. E. DO - 1471-2458-6-157 [pii] 10.1186/1471-2458-6-157 [doi] DP - Nlm ET - 06/21 KW - Adult Aged Antitubercular Agents/therapeutic use California/epidemiology Cohort Studies Communicable Disease Control/ economics/methods Contact Tracing/economics Cost-Benefit Analysis Disease Notification/ economics Emigration and Immigration Humans Isoniazid/therapeutic use Mass Screening/economics Middle Aged Population Surveillance Program Evaluation Prospective Studies Quality-Adjusted Life Years Treatment Outcome Tuberculosis, Pulmonary/ economics/epidemiology/ prevention & control LA - eng N1 - Porco, Travis C Lewis, Bryan Marseille, Elliot Grinsdale, Jennifer Flood, Jennifer M Royce, Sarah E Comparative Study Evaluation Studies Research Support, U.S. Gov't, P.H.S. England BMC public health BMC Public Health. 2006 Jun 19;6:157. PY - 2006 RN - fulltext fulltext_1208 SN - 1471-2458 (Electronic) 1471-2458 (Linking) SP - 157 ST - Cost-effectiveness of tuberculosis evaluation and treatment of newly-arrived immigrants T2 - BMC Public Health TI - Cost-effectiveness of tuberculosis evaluation and treatment of newly-arrived immigrants UR - http://www.biomedcentral.com/1471-2458/6/157 VL - 6 ID - 2486 ER - TY - JOUR AB - A theoretical framework to assess the transmission dynamics of Tuberculosis (TB) is developed. Once infected with Mycobacterium tuberculosis, individuals can either develop active TB or remain infected for the rest of their life unless endogenous reactivation or exogenous re-infection occurs. The effects of vaccination and treatment Of active TB cases suggest that even if these control strategies could have a significant effect on reducing TB incidence, the exogenous re-infection and the endogenous reactivation, mainly due to H-TV infection, will still increase the incidence of TB. AD - Univ Sao Paulo, Fac Med, Disciplina Informat Med, Inst Oscar Freire, BR-01246903 Sao Paulo, Brazil Univ Estadual Campinas, UNICAMP, IMECC, Dept Matemat Aplicada, Campinas, SP, Brazil AN - WOS:000241398400002 AU - Raimundo, S. M. AU - Yang, H. M. DA - Oct-Dec DO - 10.1080/08898480600950457 IS - 4 J2 - Math Popul Stud KW - endogenous reactivation exogenous re-infection mathematical modeling mycobacterium tuberculosis backward bifurcation epidemic model LA - English N1 - 096sz Times Cited:7 Cited References Count:18 PY - 2006 SN - 0889-8480 SP - 181-203 ST - Transmission of tuberculosis with exogenous re-infection and endogenous reactivation T2 - Mathematical Population Studies TI - Transmission of tuberculosis with exogenous re-infection and endogenous reactivation UR - ://WOS:000241398400002 VL - 13 ID - 4838 ER - TY - JOUR AB - BACKGROUND: Despite the existence of effective drug treatments, tuberculosis (TB) causes 2 million deaths annually worldwide. Effective treatment is complicated by multidrug-resistant TB (MDR TB) strains that respond only to second-line drugs. We projected the health benefits and cost-effectiveness of using drug susceptibility testing and second-line drugs in a lower-middle-income setting with high levels of MDR TB. METHODS AND FINDINGS: We developed a dynamic state-transition model of TB. In a base case analysis, the model was calibrated to approximate the TB epidemic in Peru, a setting with a smear-positive TB incidence of 120 per 100,000 and 4.5% MDR TB among prevalent cases. Secondary analyses considered other settings. The following strategies were evaluated: first-line drugs administered under directly observed therapy (DOTS), locally standardized second-line drugs for previously treated cases (STR1), locally standardized second-line drugs for previously treated cases with test-confirmed MDR TB (STR2), comprehensive drug susceptibility testing and individualized treatment for previously treated cases (ITR1), and comprehensive drug susceptibility testing and individualized treatment for all cases (ITR2). Outcomes were costs per TB death averted and costs per quality-adjusted life year (QALY) gained. We found that strategies incorporating the use of second-line drug regimens following first-line treatment failure were highly cost-effective compared to strategies using first-line drugs only. In our base case, standardized second-line treatment for confirmed MDR TB cases (STR2) had an incremental cost-effectiveness ratio of 720 dollars per QALY (8,700 dollars per averted death) compared to DOTS. Individualized second-line drug treatment for MDR TB following first-line failure (ITR1) provided more benefit at an incremental cost of 990 dollars per QALY (12,000 dollars per averted death) compared to STR2. A more aggressive version of the individualized treatment strategy (ITR2), in which both new and previously treated cases are tested for MDR TB, had an incremental cost-effectiveness ratio of 11,000 dollars per QALY (160,000 dollars per averted death) compared to ITR1. The STR2 and ITR1 strategies remained cost-effective under a wide range of alternative assumptions about treatment costs, effectiveness, MDR TB prevalence, and transmission. CONCLUSIONS: Treatment of MDR TB using second-line drugs is highly cost-effective in Peru. In other settings, the attractiveness of strategies using second-line drugs will depend on TB incidence, MDR burden, and the available budget, but simulation results suggest that individualized regimens would be cost-effective in a wide range of situations. AD - Department of Health Policy and Management, Harvard School of Public Health, Harvard University, Boston, Massachusetts, United States of America. resch@fas.harvard.edu AU - Resch, S. C. AU - Salomon, J. A. AU - Murray, M. AU - Weinstein, M. C. DO - 10.1371/journal.pmed.0030241 KW - Antitubercular Agents/administration & dosage/classification/therapeutic use Budgets Cost-Benefit Analysis Developing Countries Directly Observed Therapy/economics Disease Outbreaks Disease Transmission, Infectious/economics/prevention & control Drug Costs Health Care Costs Health Policy Humans Income Microbial Sensitivity Tests/economics Models, Economic Mycobacterium tuberculosis/drug effects/isolation & purification Peru/epidemiology Quality-Adjusted Life Years Treatment Failure Treatment Outcome Tuberculosis, Multidrug-Resistant/drug therapy/economics/microbiology/mortality/prevention & control/transmission Value of Life L1 - internal-pdf://3194378282/Resch-2006-Cost-effectiveness of treating mult.pdf N1 - LR: 20100429; GR: T32 AI07433-12/AI/NIAID NIH HHS/United States; JID: 101231360; 0 (Antitubercular Agents); CIN: PLoS Med. 2006 Dec;3(12):e539; author reply e549. PMID: 17194204; CIN: PLoS Med. 2006 Dec;3(12):e542. PMID: 17194207; OID: NLM: PMC1483913; 2005/07/06 [received]; 2006/03/24 [accepted]; ppublish PY - 2006 RN - fulltext fulltext_1208 SN - 1549-1676; 1549-1277 SP - e241 ST - Cost-effectiveness of treating multidrug-resistant tuberculosis T2 - PLoS medicine TI - Cost-effectiveness of treating multidrug-resistant tuberculosis UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1483913/pdf/pmed.0030241.pdf VL - 3 Y2 - Jul ID - 2487 ER - TY - JOUR AB - Through a rationale used in thermodynamics some "states" or "compartments" in the natural history of Tuberculosis are defined. Based oil macroscopic changes observed in the total system an attempt is made to quantify the dynamics of these changes in the following "states": "virgin of infection", "infected" and "sick". A new way to calculate the risk of becoming infected by Tuberculosis, following the laws which govern the variation of the contents in a system of compartments, is presented. A sketch showing the relationships among the considered "states", the equations of the dynamics of them and a formula to calculate the risk of infection is also presented. AD - USP, Dept Social Med, Fac Med Ribeirao Preto, Ribeirao Preto, SP, Brazil. Ruffino-Netto, A (reprint author), USP, Dept Social Med, Fac Med Ribeirao Preto, Ribeirao Preto, SP, Brazil. AN - WOS:000237699700004 AU - Ruffino-Netto, A. DA - Apr IS - 2 J2 - Rev. Saude Publica KW - tuberculosis epidemiometric models uberculosis, risk of infection epidemiology epidemiological model sensitivity Public, Environmental & Occupational Health LA - Portuguese M3 - Article; Proceedings Paper N1 - ISI Document Delivery No.: 044VA Times Cited: 0 Cited Reference Count: 18 Ruffino-Netto, A 28th annual meeting of the sociedade-brasileira-para-o-progresso-da-ciencia 1976 Brasilia, brazil Soc brasileira progresso cien 0 Revista de saude publica Sao paulo PY - 2006 SN - 0034-8910 SP - 207-217 ST - Epidemiometric models in tuberculosis - definition of "states" and risk of infection T2 - Revista De Saude Publica TI - Epidemiometric models in tuberculosis - definition of "states" and risk of infection UR - ://WOS:000237699700004 VL - 40 ID - 6125 ER - TY - JOUR AB - BACKGROUND: Development of new, effective, and affordable tuberculosis (TB) therapies has been identified as a critical priority for global TB control. As new candidates emerge from the global TB drug pipeline, the potential impacts of novel, shorter regimens on TB incidence and mortality have not yet been examined. METHODS AND FINDINGS: We used a mathematical model of TB to evaluate the expected benefits of shortening the duration of effective chemotherapy for active pulmonary TB. First, we considered general relationships between treatment duration and TB dynamics. Next, as a specific example, we calibrated the model to reflect the current situation in the South-East Asia region. We found that even with continued and rapid progress in scaling up the World Health Organization's DOTS strategy of directly observed, short-course chemotherapy, the benefits of reducing treatment duration would be substantial. Compared to a baseline of continuing DOTS coverage at current levels, and with currently available tools, a 2-mo regimen introduced by 2012 could prevent around 20% (range 13%-28%) of new cases and 25% (range 19%-29%) of TB deaths in South-East Asia between 2012 and 2030. If effective treatment with existing drugs expands rapidly, overall incremental benefits of shorter regimens would be lower, but would remain considerable (13% [range 8%-19%] and 19% [range 15%-23%] reductions in incidence and mortality, respectively, between 2012 and 2030). A ten-year delay in the introduction of new drugs would erase nearly three-fourths of the total expected benefits in this region through 2030. CONCLUSIONS: The introduction of new, shorter treatment regimens could dramatically accelerate the reductions in TB incidence and mortality that are expected under current regimens-with up to 2- or 3-fold increases in rates of decline if shorter regimens are accompanied by enhanced case detection. Continued progress in reducing the global TB burden will require a balanced approach to pursuing new technologies while promoting wider implementation of proven strategies. AD - Department of Population and International Health, Harvard School of Public Health, Boston, Massachusetts, United States of America. jsalomon@hsph.harvard.edu AN - 16866578 AU - Salomon, J. A. AU - Lloyd-Smith, J. O. AU - Getz, W. M. AU - Resch, S. AU - Sanchez, M. S. AU - Porco, T. C. AU - Borgdorff, M. W. DA - Aug DO - 05-PLME-RA-0399R2 [pii] 10.1371/journal.pmed.0030273 [doi] DP - Nlm ET - 07/27 KW - Antitubercular Agents/administration & dosage/ therapeutic use Asia, Southeastern/epidemiology Communicable Disease Control/ trends Directly Observed Therapy Drug Administration Schedule Drug Design Humans Incidence Models, Theoretical Patient Compliance Recurrence/prevention & control Tuberculosis/ drug therapy/epidemiology/prevention & control World Health Organization LA - eng N1 - Salomon, Joshua A Lloyd-Smith, James O Getz, Wayne M Resch, Stephen Sanchez, Maria S Porco, Travis C Borgdorff, Martien W T32 AI007433-10/AI/NIAID NIH HHS/United States Research Support, Non-U.S. Gov't United States PLoS medicine PLoS Med. 2006 Aug;3(8):e273. PY - 2006 RN - fulltext fulltext_1208 SN - 1549-1676 (Electronic) 1549-1277 (Linking) SP - e273 ST - Prospects for advancing tuberculosis control efforts through novel therapies T2 - PLoS Med TI - Prospects for advancing tuberculosis control efforts through novel therapies UR - http://www.plosmedicine.org/article/fetchObjectAttachment.action?uri=info%3Adoi%2F10.1371%2Fjournal.pmed.0030273&representation=PDF VL - 3 ID - 2488 ER - TY - JOUR AN - 15740 AU - Shrestha, R. K. AU - Mugisha, B. AU - Bunnell, R. AU - Mermin, J. AU - Hitimana-Lukanika, C. AU - Odeke, R. AU - Madra, P. AU - Adatu, F. AU - Blandford, J. M. KW - Africa cost effectiveness HIV isoniazid preventive therapy tuberculin testing Uganda Preventive Therapy TB and HIV N1 - TB Periodical PY - 2006 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SP - 656-662 ST - Cost-effectiveness of including tuberculin skin testing in an IPT program for HIV-infected persons in Uganda T2 - International Journal of Tuberculosis and Lung Disease TI - Cost-effectiveness of including tuberculin skin testing in an IPT program for HIV-infected persons in Uganda UR - file://C:\literature_pdf\rm15740.pdf VL - 10 ID - 2489 ER - TY - JOUR AB - Tuberculosis is the number one cause of death due to infectious disease in the world today. Understanding the dynamics of the immune response is crucial to elaborating differences between individuals who contain infection vs those who suffer active disease. Key cells in an adaptive immune response to intracellular pathogens include CD8(+) T cells. Once stimulated, these cells provide a number of different effector functions, each aimed at clearing or containing the pathogen. To explore the role of CD8(+) T cells in an integrative way, we synthesize both published and unpublished data to build and test a mathematical model of the immune response to Mycobacterium tuberculosis in the lung. The model is then used to perform a series of simulations mimicking experimental situations. Selective deletion of CD8(+) T cell subsets suggests a differential contribution for CD8(+) T cell effectors that are cytotoxic as compared with those that produce IFN-gamma. We also determined the minimum levels of effector memory cells of each T cell subset (CD4(+) and CD8(+)) in providing effective protection following vaccination. AD - Department of Biomedical Engineering, College of Engineering, University of Michigan, Ann Arbor, 48109, USA. AN - 16547267 AU - Sud, D. AU - Bigbee, C. AU - Flynn, J. L. AU - Kirschner, D. E. DA - Apr 01 IS - 7 KW - Animals CD8-Positive T-Lymphocytes/*immunology/metabolism Cells, Cultured Interleukin-10/pharmacology Kinetics Macrophages/drug effects/metabolism Mice Mycobacterium tuberculosis/*immunology Tuberculosis/*immunology/metabolism/*microbiology N1 - Sud, Dhruv Bigbee, Carolyn Flynn, Joanne L Kirschner, Denise E eng AI37859/AI/NIAID NIH HHS/ R01 HL62119/HL/NHLBI NIH HHS/ R01 HL68526/HL/NHLBI NIH HHS/ Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't 2006/03/21 09:00 J Immunol. 2006 Apr 1;176(7):4296-314. PY - 2006 SN - 0022-1767 (Print) 0022-1767 (Linking) SP - 4296-314 ST - Contribution of CD8+ T cells to control of Mycobacterium tuberculosis infection T2 - J Immunol TI - Contribution of CD8+ T cells to control of Mycobacterium tuberculosis infection UR - https://www.ncbi.nlm.nih.gov/pubmed/16547267 VL - 176 ID - 2232 ER - TY - JOUR AB - Infection with Mycobacterium tuberculosis (Mtb) is characterized by localized, roughly spherical lesions within which the pathogen interacts with host cells. Containment of the infection or progression of disease depends on the behavior of individual cells, which, in turn, depends on the local molecular environment and on contact with neighboring cells. Modeling can help us understand the nonlinear interactions that drive the overall dynamics in this system. Early events in infection are particularly important, as are spatial effects and inherently stochastic processes. We describe a model of early Mycobacterium infection using the CyCells simulator, which was designed to capture these effects. We relate CyCells simulations of the model to several experimental observations of individual components of the response to Mtb. AD - Department of Computer Science, University of New Mexico, P.O. Box 5800 MS 1423, Albuquerque, NM 87185-1423, USA. cewarr@sandia.gov AN - 17086496 AU - Warrender, C. AU - Forrest, S. AU - Koster, F. DA - Nov DO - 10.1007/s11538-006-9103-y [doi] DP - Nlm ET - 11/07 KW - Computer Simulation Humans Interferon-gamma/immunology Interleukin-10/immunology Macrophages, Alveolar/immunology/microbiology Models, Biological Mycobacterium tuberculosis/ physiology T-Lymphocytes/immunology/microbiology Tuberculosis/immunology/ microbiology Tumor Necrosis Factor-alpha/immunology LA - eng N1 - Warrender, Christina Forrest, Stephanie Koster, Frederick P20 GM066283/GM/NIGMS NIH HHS/United States R-1P20RR18754/RR/NCRR NIH HHS/United States U54 AI057156/AI/NIAID NIH HHS/United States Research Support, N.I.H., Extramural Research Support, U.S. Gov't, Non-P.H.S. United States Bulletin of mathematical biology Bull Math Biol. 2006 Nov;68(8):2233-61. Epub 2006 May 20. PY - 2006 RN - fulltext fulltext_1208 SN - 0092-8240 (Print) 0092-8240 (Linking) SP - 2233-61 ST - Modeling intercellular interactions in early Mycobacterium infection T2 - Bull Math Biol TI - Modeling intercellular interactions in early Mycobacterium infection UR - http://www.springerlink.com/content/f698424230324675/ VL - 68 ID - 2490 ER - TY - JOUR AB - The aim of the present study was to compare the direct costs of three models for detection of latent tuberculosis infection (LTBI) in routine clinical practice in Switzerland. Comparison of the overall costs of screening for LTBI, including medical and radiological examination, and preventive treatment associated with three screening models was carried out. Model 1 relies only on the tuberculin skin test (TST) according to the current national guidelines, model 2 relies on T-SPOT.TB (Oxford Immunotec, Oxford, UK) only and model 3 relies on TST followed by confirmation of positive results by T-SPOT.TB. Costs were taken directly from the clinic's figures. Clinical assumptions were based on the 267 patients who were referred to the clinic over the study period. Model 3 was found to be the most cost-effective. Using only the skin test (model 1) was the least cost-effective. If only one test for LTBI is to be used, then model 2 (using T-SPOT.TB only) is cheaper than using the TST (model 1). Screening for latent tuberculosis infection by tuberculin skin test followed by confirmation with T-SPOT.TB is less costly than screening with tuberculin skin test alone, as it allows a reduction in the number of people who receive preventive treatment. In groups with a high proportion of negative tuberculin skin tests, screening with T-SPOT.TB test only may be the most cost-effective. AD - University Medical Policlinic, Rue du Bugnon 44, 1011 Lausanne, Switzerland. AU - Wrighton-Smith, P. AU - Zellweger, J. P. DO - 10.1183/09031936.06.00005906 KW - Cost-Benefit Analysis Decision Support Techniques Humans Interferon-gamma/metabolism Mass Screening/economics/methods Mycobacterium tuberculosis/metabolism Public Health/methods Reagent Kits, Diagnostic Sensitivity and Specificity Switzerland Tuberculin Test/economics/methods Tuberculosis/diagnosis N1 - LR: 20081121; JID: 8803460; 0 (Reagent Kits, Diagnostic); 82115-62-6 (Interferon-gamma); 2006/04/12 [aheadofprint]; 2006/05/31 [aheadofprint]; ppublish PY - 2006 RN - fulltext fulltext_1208 SN - 0903-1936; 0903-1936 SP - 45-50 ST - Direct costs of three models for the screening of latent tuberculosis infection T2 - The European respiratory journal : official journal of the European Society for Clinical Respiratory Physiology TI - Direct costs of three models for the screening of latent tuberculosis infection VL - 28 Y2 - Jul ID - 2491 ER - TY - BILL AB - BACKGROUND: San Francisco has the highest rate of tuberculosis (TB) in the U.S. with recurrent outbreaks among the homeless and marginally housed. It has been shown for syndromic data that when exact geographic coordinates of individual patients are used as the spatial base for outbreak detection, higher detection rates and accuracy are achieved compared to when data are aggregated into administrative regions such as zip codes and census tracts. We examine the effect of varying the spatial resolution in the TB data within the San Francisco homeless population on detection sensitivity, timeliness, and the amount of historical data needed to achieve better performance measures. METHODS AND FINDINGS: We apply a variation of space-time permutation scan statistic to the TB data in which a patient's location is either represented by its exact coordinates or by the centroid of its census tract. We show that the detection sensitivity and timeliness of the method generally improve when exact locations are used to identify real TB outbreaks. When outbreaks are simulated, while the detection timeliness is consistently improved when exact coordinates are used, the detection sensitivity varies depending on the size of the spatial scanning window and the number of tracts in which cases are simulated. Finally, we show that when exact locations are used, smaller amount of historical data is required for training the model. CONCLUSION: Systematic characterization of the spatio-temporal distribution of TB cases can widely benefit real time surveillance and guide public health investigations of TB outbreaks as to what level of spatial resolution results in improved detection sensitivity and timeliness. Trading higher spatial resolution for better performance is ultimately a tradeoff between maintaining patient confidentiality and improving public health when sharing data. Understanding such tradeoffs is critical to managing the complex interplay between public policy and public health. This study is a step forward in this direction. AD - MITRE Corporation, McLean, Virginia, United States of America. bhiggs100@yahoo.com AN - 18074010 DA - Jan 1 KW - Disease Outbreaks Population Surveillance Humans Tuberculosis Prevalence San Francisco Sensitivity and Specificity LB - p02029 M1 - 12 PY - 2007 RN - fulltext fulltext_1208 SP - e1284 ST - Early detection of tuberculosis outbreaks among the San Francisco homeless: trade-offs between spatial resolution and temporal scale T2 - PLoS ONE TI - Early detection of tuberculosis outbreaks among the San Francisco homeless: trade-offs between spatial resolution and temporal scale UR - http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0001284 VL - 2 ID - 2506 ER - TY - BILL AB - OBJECTIVE: To model the effect of socio-economic deprivation and a few transmission-related indicators of the tuberculosis (TB) incidence at small area level, to discuss the potential of each indicator in targeting places for developing preventive action. METHODS: Ecological spatial study of TB incidence in Olinda, a city in the north-east of Brazil, during the period 1996-2000. Three socio-economic indicators (mean number of inhabitants per household; percentage of heads of household with <1 year's formal education; percentage of heads of households with monthly income lower than the minimum wage) and two transmission-related indicators (number of cases of retreatment; number of households with more than one case during the period under study), all calculated per census tract, were used. We adopted four different full hierarchical Bayesian models to estimate the relative risk of the occurrence of TB via Markov chain Monte Carlo. RESULTS: The best specified model includes all the selected covariates and the spatially structured random effect. The gain in goodness-of-fit statistic when the spatial structure was included confirms the clustered spatial pattern of disease and poverty. In this model, the covariates within the non-zero credibility interval were the number of persons per house, the number of cases of retreatment and the number of households with more than one case (all with relative risk > or = 1.8) in each census tract. CONCLUSIONS: The possibility to estimate in the same framework both the contribution of covariates at ecological level and the spatial pattern should be encouraged in epidemiology, and may help with establishing Epidemiological Surveillance Systems on a territorial basis, that allows rational planning of interventions and improvement of the Control Programme effectiveness. AD - Aggeu Magalhães Research Centre, Oswaldo Cruz Foundation, Recife, Brazil. wayner@cpqam.fiocruz.br AN - 17286622 DA - Mar 1 KW - Bayes Theorem Income Humans Risk Factors Brazil Urban Health Population Surveillance Models: Statistical Residence Characteristics Tuberculosis: Pulmonary Incidence Socioeconomic Factors Psychosocial Deprivation LB - p02031 M1 - 3 PY - 2007 RN - fulltext fulltext_1208 SP - 323-30 ST - Tuberculosis in intra-urban settings: a Bayesian approach T2 - Trop Med Int Health TI - Tuberculosis in intra-urban settings: a Bayesian approach UR - http://www3.interscience.wiley.com/journal/118506949/abstract VL - 12 ID - 2511 ER - TY - JOUR AU - Adetunde, I. A. IS - 9 PY - 2007 SP - 943-946 ST - The mathematical models of the dynamical behaviour of tuberculosis disease in the Upper East Region of the northern part of Ghana: a case study of Bawku T2 - Research Journal of Applied Sciences TI - The mathematical models of the dynamical behaviour of tuberculosis disease in the Upper East Region of the northern part of Ghana: a case study of Bawku UR - http://docsdrive.com/pdfs/medwelljournals/rjasci/2007/943-946.pdf VL - 2 ID - 4935 ER - TY - JOUR AB - Mathematical models for the population dynamics of de novo resistant Mycobacterium tuberculosis within individuals are studied. The models address the use of one or two antimicrobial drugs for treating latent tuberculosis (TB). They consider the effect of varying individual immune response strength on the dynamics for the appearance of resistant bacteria. From the analysis of the models, equilibria and local stabilities are determined. For assessing temporal dynamics and global stability for sensitive and drug-resistant bacteria, numerical simulations are used. Results indicate that for a low bacteria load that is characteristic of latent TB and for small reduction in an immune response, the use of a single drug is capable of curing the infection before the appearance of drug resistance. However, for severe immune deficiency, the use of two drugs will provide a larger time period before the emergence of resistance. Therefore, in this case, two-drugs treatment will be more efficient in controlling the infection. AD - Division Academica de Ciencias Basicas, Universidad Juarez Autonoma de Tabasco, Cunduacan 86690, Tabasco, Mexico. AN - 17060491 AU - Alavez-Ramirez, J. AU - Castellanos, J. R. AU - Esteva, L. AU - Flores, J. A. AU - Fuentes-Allen, J. L. AU - Garcia-Ramos, G. AU - Gomez, G. AU - Lopez-Estrada, J. DA - Mar DO - 10.1093/imammb/dql026 ET - 2006/10/25 IS - 1 J2 - Mathematical medicine and biology : a journal of the IMA KW - Algorithms Anti-Bacterial Agents/*pharmacology/therapeutic use Computer Simulation *Drug Resistance, Microbial Drug Therapy, Combination Granuloma/drug therapy/microbiology Humans Isoniazid/pharmacology/therapeutic use *Models, Biological Mycobacterium tuberculosis/*drug effects/growth & development Rifampin/pharmacology/therapeutic use Tuberculosis, Pulmonary/drug therapy/*microbiology L1 - internal-pdf://0462474380/Alavez-Ramirez IMA.pdf LA - eng N1 - Alavez-Ramirez, Justino Castellanos, J Rogelio Avendano Esteva, Lourdes Flores, Jose Antonio Fuentes-Allen, Jose Luis Garcia-Ramos, Gisela Gomez, Guillermo Lopez-Estrada, Jesus England Math Med Biol. 2007 Mar;24(1):35-56. Epub 2006 Oct 23. PY - 2007 RN - fulltext fulltext_1208 SN - 1477-8599 (Print) 1477-8599 (Linking) SP - 35-56 ST - Within-host population dynamics of antibiotic-resistant M. tuberculosis T2 - Math Med Biol TI - Within-host population dynamics of antibiotic-resistant M. tuberculosis UR - http://www.ncbi.nlm.nih.gov/pubmed/17060491 http://imammb.oxfordjournals.org/content/24/1/35 VL - 24 ID - 144 ER - TY - JOUR AB - Contact tracing (also known as partner notification) is a primary means of controlling infectious diseases such as tuberculosis (TB), human immunodeficiency virus (HIV), and sexually transmitted diseases (STDs). However, little work has been done to determine the optimal level of investment in contact tracing. In this paper, we present a methodology for evaluating the appropriate level of investment in contact tracing. We develop and apply a simulation model of contact tracing and the spread of an infectious disease among a network of individuals in order to evaluate the cost and effectiveness of different levels of contact tracing. We show that contact tracing is likely to have diminishing returns to scale in investment: incremental investments in contact tracing yield diminishing reductions in disease prevalence. In conjunction with a cost-effectiveness threshold, we then determine the optimal amount that should be invested in contact tracing. We first assume that the only incremental disease control is contact tracing. We then extend the analysis to consider the optimal allocation of a budget between contact tracing and screening for exogenous infection, and between contact tracing and screening for endogenous infection. We discuss how a simulation model of this type, appropriately tailored, could be used as a policy tool for determining the appropriate level of investment in contact tracing for a specific disease in a specific population. We present an example application to contact tracing for chlamydia control. AD - Department of Management Science and Engineering, Stanford University, Stanford, CA 94305-4026, USA. armbruster@stanford.edu AN - 18074967 AU - Armbruster, B. AU - Brandeau, M. L. DA - Dec DP - Nlm ET - 12/14 J2 - Health care management science KW - Chlamydia Infections/epidemiology/transmission Contact Tracing/ economics/utilization Cost-Benefit Analysis Humans Mass Screening United States/epidemiology LA - eng N1 - Armbruster, Benjamin Brandeau, Margaret L PY - 2007 RN - fulltext fulltext_1208 SN - 1386-9620 (Print) 1386-9620 (Linking) SP - 341-55 ST - Contact tracing to control infectious disease: when enough is enough T2 - Health Care Manag Sci TI - Contact tracing to control infectious disease: when enough is enough UR - http://www.springerlink.com/content/f7171782467075v1/fulltext.pdf VL - 10 ID - 2493 ER - TY - JOUR AB - We used a system dynamics simulation model of the transmission dynamics of drug-sensitive tuberculosis (DSTB), multidrug-resistant tuberculosis (MDRTB) and HIV to estimate the impact of coverage with highly active antiretroviral therapy (HAART) and different cure rates for MDRTB in settings of explosive HIV epidemics and high MDRTB levels. Population coverage levels at 0%, 25%, 50%, 75% and 100% for HAART, and 5% and 80% of MDRTB treatment cure rates were simulated over a 10-year period and cumulative deaths from tuberculosis and HIV-associated tuberculosis were estimated for populations with latent tuberculosis, DSTB, MDRTB, HIV and HIV-associated tuberculosis. Depending on levels of HAART population coverage, increasing MDRTB cure rates from 5% to 80% reduces cumulative tuberculosis deaths by 1% and 13%. High population coverage with HAART (75% or higher), allied with high MDRTB cure rates, reduces cumulative deaths by 60%, with limited impact below this level. High coverage with HAART is required to substantially reduce the number of deaths from tuberculosis. AD - Centre for Health Management, Tanaka Business School, Imperial College London, South Kensington Campus, London, UK. r.atun@imperial.ac.uk AN - 17509178 AU - Atun, R. A. AU - Lebcir, R. M. AU - Drobniewski, F. AU - McKee, M. AU - Coker, R. J. DA - Apr DO - 10.1258/095646207780659024 [doi] DP - Nlm ET - 05/19 KW - AIDS-Related Opportunistic Infections/drug therapy/ prevention & control Antiretroviral Therapy, Highly Active/ utilization Disease Transmission, Infectious/ prevention & control HIV Infections/ drug therapy Humans Models, Biological Russia/epidemiology Tuberculosis, Multidrug-Resistant/epidemiology/ prevention & control L1 - internal-pdf://4034003261/095646207780659024.pdf LA - eng N1 - Atun, Rifat A Lebcir, Reda M Drobniewski, Francis McKee, Martin Coker, Richard J Research Support, Non-U.S. Gov't England International journal of STD & AIDS Int J STD AIDS. 2007 Apr;18(4):267-73. PY - 2007 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 0956-4624 (Print) 0956-4624 (Linking) SP - 267-73 ST - High coverage with HAART is required to substantially reduce the number of deaths from tuberculosis: system dynamics simulation T2 - Int J STD AIDS TI - High coverage with HAART is required to substantially reduce the number of deaths from tuberculosis: system dynamics simulation UR - http://ijsa.rsmjournals.com/content/18/4/267http://ijsa.rsmjournals.com/content/18/4/267.full.pdf VL - 18 ID - 2494 ER - TY - JOUR AB - A mathematical model of the spread of tuberculosis taking into account the impact of the antituberculosis programs was considered. The singularity of the proposed model lies in making explicit discrimination between the detected and overlooked patients and taking into account their migration. Studies demonstrated insufficiency of the standard accounting form of the regional Russian antituberculosis institutions. Proposed was a submodel enabling objective estimation of the patient detection system on the basis of individualized database. These estimates corroborated the assumption of a substantial nonuniformity of the Russian regions in terms of tuberculosis morbidity and efficiency of patient detection. For example, the rates of patient detection can differ by the factor of five through six. The model can be used to forecast the tuberculosis morbidity and efficiency of the antituberculosis programs. AD - Russian Acad Sci, Inst Numer Math, Moscow, Russia AN - WOS:000249805000015 AU - Avilov, K. K. AU - Romanyukha, A. A. DA - Sep DO - 10.1134/S0005117907090159 IS - 9 J2 - Automat Rem Contr+ KW - risks LA - English N1 - 215jq Times Cited:7 Cited References Count:15 PY - 2007 SN - 0005-1179 SP - 1604-1617 ST - Mathematical modeling of tuberculosis propagation and patient detection T2 - Automation and Remote Control TI - Mathematical modeling of tuberculosis propagation and patient detection UR - ://WOS:000249805000015 VL - 68 ID - 4840 ER - TY - JOUR AB - BACKGROUND: Extensively drug-resistant (XDR) tuberculosis has spread among hospitalised patients in South Africa, but the epidemic-level effect of hospital-based infection control strategies remains unknown. We modelled the plausible effect of rapidly available infection control strategies on the overall course of the XDR tuberculosis epidemic in a rural area of South Africa. METHODS: We investigated the effect of administrative, environmental, and personal infection control measures on the epidemic trajectory of XDR tuberculosis in the rural community of Tugela Ferry. Assessments were done with a mathematical model incorporating over 2 years of longitudinal inpatient and community-based data. The model simulated inpatient airborne tuberculosis transmission, community tuberculosis transmission, and the effect of HIV and antiretroviral therapy. FINDINGS: If no new interventions are introduced, about 1300 cases of XDR tuberculosis are predicted to occur in the area of Tugela Ferry by the end of 2012, more than half of which are likely to be nosocomially transmitted. Mask use alone would avert fewer than 10% of cases in the overall epidemic, but could prevent a large proportion of cases of XDR tuberculosis in hospital staff. The combination of mask use with reduced hospitalisation time and a shift to outpatient therapy could prevent nearly a third of XDR tuberculosis cases. Supplementing this approach with improved ventilation, rapid drug resistance testing, HIV treatment, and tuberculosis isolation facilities could avert 48% of XDR tuberculosis cases (range 34-50%) by the end of 2012. However, involuntary detention could result in an unexpected rise in incidence due to restricted isolation capacity. INTERPRETATION: A synergistic combination of available nosocomial infection control strategies could prevent nearly half of XDR tuberculosis cases, even in a resource-limited setting. XDR tuberculosis transmission will probably continue in the community, indicating the need to develop and implement parallel community-based programmes. AD - Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, CT 06520, USA. sanjay.basu@yale.edu AN - 17964351 AU - Basu, S. AU - Andrews, J. R. AU - Poolman, E. M. AU - Gandhi, N. R. AU - Shah, N. S. AU - Moll, A. AU - Moodley, P. AU - Galvani, A. P. AU - Friedland, G. H. DA - Oct 27 DO - S0140-6736(07)61636-5 [pii] 10.1016/S0140-6736(07)61636-5 [doi] DP - Nlm ET - 10/30 KW - Cross Infection/ prevention & control/transmission Hospitals, District Humans Models, Theoretical Rural Health South Africa/epidemiology Tuberculosis, Multidrug-Resistant/epidemiology/ prevention & control/transmission L1 - internal-pdf://1337477870/Basu-2007-Prevention of nosocomial transmissio.pdf LA - eng N1 - Basu, Sanjay Andrews, Jason R Poolman, Eric M Gandhi, Neel R Shah, N Sarita Moll, Anthony Moodley, Prashini Galvani, Alison P Friedland, Gerald H 5 T32 GM07205-32/GM/NIGMS NIH HHS/United States R01 AI068932/AI/NIAID NIH HHS/United States R01 AI072706/AI/NIAID NIH HHS/United States Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. England Lancet Lancet. 2007 Oct 27;370(9597):1500-7. PY - 2007 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1474-547X (Electronic) 0140-6736 (Linking) SP - 1500-7 ST - Prevention of nosocomial transmission of extensively drug-resistant tuberculosis in rural South African district hospitals: an epidemiological modelling study T2 - Lancet TI - Prevention of nosocomial transmission of extensively drug-resistant tuberculosis in rural South African district hospitals: an epidemiological modelling study UR - http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(07)61636-5/fulltexthttp://ac.els-cdn.com/S0140673607616365/1-s2.0-S0140673607616365-main.pdf?_tid=e27df51c-f0e6-11e1-879f-00000aacb35e&acdnat=1346141203_b98aeedbc04189a4bb89b46e525174b1 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3711808/pdf/nihms-35061.pdf VL - 370 ID - 2496 ER - TY - JOUR AB - We propose that microbes that have developed persistent relationships with human hosts have evolved cross-signalling mechanisms that permit homeostasis that conforms to Nash equilibria and, more specifically, to evolutionarily stable strategies. This implies that a group of highly diverse organisms has evolved within the changing contexts of variation in effective human population size and lifespan, shaping the equilibria achieved, and creating relationships resembling climax communities. We propose that such ecosystems contain nested communities in which equilibrium at one level contributes to homeostasis at another. The model can aid prediction of equilibrium states in the context of further change: widespread immunodeficiency, changing population densities, or extinctions. AD - Department of Medicine, New York University School of Medicine, New York, New York 10016, USA. martin.blaser@med.nyu.edu AN - 17943121 AU - Blaser, M. J. AU - Kirschner, D. DO - nature06198 [pii] 10.1038/nature06198 KW - *Bacterial Physiological Phenomena Helicobacter pylori/immunology/physiology *Host-Pathogen Interactions Humans *Models, Biological Mycobacterium tuberculosis/immunology/physiology Salmonella typhi/immunology/physiology LA - eng N1 - Blaser, Martin J Kirschner, Denise Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't England Nature Nature. 2007 Oct 18;449(7164):843-9. PY - 2007 RN - fulltext fulltext_1208 SN - 1476-4687 (Electronic) 0028-0836 (Linking) SP - 843-849 ST - The equilibria that allow bacterial persistence in human hosts T2 - Nature TI - The equilibria that allow bacterial persistence in human hosts UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=17943121 VL - 449 ID - 2497 ER - TY - JOUR AB - Infection with Mycobacterium tuberculosis leads to tuberculosis (TB) disease by one of the three possible routes: primary progression after a recent infection; re-activation of a latent infection; or exogenous re-infection of a previously infected individual. Recent studies show that optimal TB control strategies may vary depending on the predominant route to disease in a specific population. It is therefore important for public health policy makers to understand the relative frequency of each type of TB within specific epidemiological scenarios. Although molecular epidemiologic tools have been used to estimate the relative contribution of recent transmission and re-activation to the burden of TB disease, it is not possible to use these techniques to distinguish between primary disease and re-infection on a population level. Current estimates of the contribution of re-infection therefore rely on mathematical models which identify the parameters most consistent with epidemiological data; these studies find that exogenous re-infection is important only when TB incidence is high. A basic assumption of these models is that people in a population are all equally likely to come into contact with an infectious case. However, theoretical studies demonstrate that the social and spatial structure can strongly influence the dynamics of infectious disease transmission. Here, we use a network model of TB transmission to evaluate the impact of non-homogeneous mixing on the relative contribution of re-infection over realistic epidemic trajectories. In contrast to the findings of previous models, our results suggest that re-infection may be important in communities where the average disease incidence is moderate or low as the force of infection can be unevenly distributed in the population. These results have important implications for the development of TB control strategies. AD - Division of Social Medicine and Health Inequalities, Brigham and Women's Hospital, One Brigham Circle, Boston, MA 02120, USA tcohen@hsph.harvard.edu AN - 17251134 AU - Cohen, T. AU - Colijn, C. AU - Finklea, B. AU - Murray, M. DA - Jun 22 DO - PJ25346278M18447 [pii] 10.1098/rsif.2006.0193 [doi] DP - Nlm ET - 01/26 KW - Cluster Analysis Disease Outbreaks/prevention & control Europe/epidemiology Humans Models, Biological Tuberculosis, Pulmonary/ epidemiology/prevention & control/ transmission LA - eng N1 - Cohen, Ted Colijn, Caroline Finklea, Bryson Murray, Megan K08 AI055985-05/AI/NIAID NIH HHS/United States England Journal of the Royal Society, Interface / the Royal Society J R Soc Interface. 2007 Jun 22;4(14):523-31. PY - 2007 RN - fulltext fulltext_1208 SN - 1742-5689 (Print) 1742-5662 (Linking) SP - 523-31 ST - Exogenous re-infection and the dynamics of tuberculosis epidemics: local effects in a network model of transmission T2 - J R Soc Interface TI - Exogenous re-infection and the dynamics of tuberculosis epidemics: local effects in a network model of transmission UR - http://rsif.royalsocietypublishing.org/content/4/14/523.full.pdf VL - 4 ID - 2498 ER - TY - JOUR AB - Tuberculosis is a disease of global importance: over 2 million deaths are attributed to this infectious disease each year. Even in areas where tuberculosis is in decline, there are sporadic outbreaks which are often attributed either to increased host susceptibility or increased strain transmissibility and virulence. Using two mathematical models, we explore the role of the contact structure of the population, and find that in declining epidemics, localized outbreaks may occur as a result of contact heterogeneity even in the absence of host or strain variability. We discuss the implications of this finding for tuberculosis control in low incidence settings. AD - Department of Epidemiology, Harvard School of Public Health, Boston, MA, USA. ccolijn@hsph.harvard.edu AN - 17540410 AU - Colijn, C. AU - Cohen, T. AU - Murray, M. DA - Aug 21 DO - S0022-5193(07)00197-X [pii] 10.1016/j.jtbi.2007.04.015 [doi] DP - Nlm ET - 06/02 KW - Antitubercular Agents/therapeutic use Communicable Disease Control Disease Outbreaks Disease Susceptibility Disease Transmission, Infectious Humans Incidence Models, Biological Models, Statistical Mycobacterium tuberculosis Tuberculosis, Pulmonary/drug therapy/ epidemiology/transmission World Health LA - eng N1 - Colijn, Caroline Cohen, Ted Murray, Megan K08 AI055985-05/AI/NIAID NIH HHS/United States Netherlands Journal of theoretical biology Nihms94733 J Theor Biol. 2007 Aug 21;247(4):765-74. Epub 2007 Apr 27. PY - 2007 RN - fulltext fulltext_1208 SN - 0022-5193 (Print) 0022-5193 (Linking) SP - 765-74 ST - Emergent heterogeneity in declining tuberculosis epidemics T2 - J Theor Biol TI - Emergent heterogeneity in declining tuberculosis epidemics UR - http://ac.els-cdn.com/S002251930700197X/1-s2.0-S002251930700197X-main.pdf?_tid=701971423bef0a352e3f5d824a965769&acdnat=1345012153_4a5156ce5fbcc81695d4f605ae8bcb3a VL - 247 ID - 2499 ER - TY - JOUR AB - Tuberculosis is a leading cause of infectious mortality. Although anti-biotic treatment is available and there is vaccine, tuberculosis levels are rising in many areas of the world. The recent emergence of drug-resistant of TB is alarming, as are the potential effects of HIV on TB epidemics. Mathematical models have been used to study tuberculosis in the past and have influenced policy; there is renewed opportunity for mathematical models to contribute today. Here we review and compare the mathematical models of tuberculosis dynamics in the literature. We present two models of our own: a spatial stochastic individual-based model and a set of delay differential equations encapsulating the same biological assumptions. We compare two different assumptions about partial immunity and explore the effect of preventative treatments. We argue that seemingly subtle differences in model assumptions can have significant effects on biological conclusions. AD - Harvard Univ, Sch Publ Hlth, Kresge Bldg,677 Huntington Ave, Boston, MA 02138 USA Infect Dis Unit, Massachusetts Gen Hosp, Boston, MA 02114 USA AN - WOS:000261596200008 AU - Colijn, C. AU - Cohen, T. AU - Murray, M. DO - Doi 10.1142/9789812708779_0008 KW - intrinsic transmission dynamics drug-resistant tuberculosis mycobacterium-tuberculosis amplification dynamics reinfection threshold exogenous reinfection epidemiological model published literature epidemics infection LA - English N1 - Bip52 Times Cited:3 Cited References Count:60 PY - 2007 SP - 123-+ ST - Mathematical Models of Tuberculosis: Accomplishments and Future Challenges T2 - Biomat 2006 TI - Mathematical Models of Tuberculosis: Accomplishments and Future Challenges UR - ://WOS:000261596200008 http://www.worldscientific.com/doi/abs/10.1142/9789812708779_0008 ID - 4837 ER - TY - JOUR AB - Tuberculosis still remains as a serious public health problem. Thinking about more efficient interventions for its combat and control WHO advocates that DOTS (Directly Observed Short-time Treatment Strategy) can improve cure rates and case detection. In this context, mathematical modeling can be used to evaluate the behavior of tuberculosis under DOTS, supplying informations to optimal action strategies. The model presented in this work, describes the dynamic of 4 individuals groups: susceptibles, never before infected; latently-infected or cured of TB under chemotherapy; infectious individuals with pulmonary TB and sputum smear positive; and noninfectious with pulmonary TB but sputum-smear negative or extra-pulmonary TB. Individuals, who complete treatment successfull, are cured of tuberculosis but remain infected and individuals, who do not complete treatment, continue with the illness (infectious or noninfectious). The model, as considered here allows us to evaluate the effect of improve cure rates and case detection. The Effective Reproductive Rate (R(0)(e)) was found for this model and used as epidemiological measure of severity of an epidemics. If R(0)(e) > 1, an epidemics occurs and if R(0)(e) < 1, it is eradicated. The time-dependent uncertainty analysis is presented using the Monte Carlo Method. AD - Comes, PD Univ Fed Fluminense, Inst Comp, Rua Passo Patria 156,Bloco E Salsa 301 Sao Doming, BR-24210240 Niteroi, RJ, Brazil Univ Fed Fluminense, Inst Comp, Rua Passo Patria 156,Bloco E Salsa 301 Sao Doming, BR-24210240 Niteroi, RJ, Brazil Univ Fed Fluminense, Inst Comp, BR-24210240 Niteroi, RJ, Brazil AN - WOS:000261596200010 AU - Comes, P. D. AU - Leal-Toledo, R. C. P. AU - Cunha, C. E. C. KW - transmission sensitivity uncertainty example model LA - English N1 - Bip52 Times Cited:0 Cited References Count:25 PY - 2007 SP - 161-180 ST - Dynamics of Tuberculosis under Dots Strategy T2 - Biomat 2006 TI - Dynamics of Tuberculosis under Dots Strategy UR - ://WOS:000261596200010 ID - 4841 ER - TY - JOUR AB - OBJECTIVES: To assess the cost-effectiveness of the new QuantiFERON-TB Gold In-Tube (QFT-G) [Cellestis; Carnegie, VIC, Australia] assay for screening and treating of persons who have had close contact with tuberculosis (TB) patients and are suspected of having latent tuberculosis infection (LTBI) [hereafter called close-contacts] in Germany. METHODS: The health and economic outcomes of isoniazid treatment of 20-year-old close-contacts were compared in a Markov model over a period of 20 years, using two different cutoff values for the tuberculin skin test (TST), the QFT-G assay alone, or the QFT-G assay as a confirmatory test for the TST results. RESULTS: QFT-G assay-based treatment led to cost savings of $542.9 and 3.8 life-days gained per LTBI case. TST-based treatment at a 10-mm induration size cutoff gained $177.4 and 2.0 life-days gained per test-positive contact. When the cutoff induration size for the TST was reduced to 5 mm, the incremental cost-effectiveness ratio fell below the willingness-to-pay threshold ($30,170 per life-years gained) but resulted in unnecessary treatment of 77% of contacts owing to false-positive TST results. Combination with the 5-mm induration size TST cutoff value compared to the results of the QFT-G assay alone reduced the total costs per 1,000 contacts by 1.8% to $222,869. The number treated to prevent 1 TB case was 22 for the two QFT-G assay-based procedures, 40 for the TST at a cutoff induration size of 10 mm, and 96 for the TST at a cutoff induration size of 5 mm. When the sensitivity rates of the TST and the QFT-G assay were compounded, the QFT-G assay strategy alone was slightly less costly (0.6%) than the two-step approach. CONCLUSIONS: Using the QFT-G assay, but especially combining the QFT-G assay following the TST screening of close-contacts at a cutoff induration size of 5 mm before LTBI treatment is highly cost-effective in reducing the disease burden of TB. AD - School of Public Health, c/o Institute for Medical Sociology, Heinrich Heine University, Post Box 101007, D-40001 Dusseldorf, Germany. Roland.Diel@uni-duesseldorf.de AU - Diel, R. AU - Nienhaus, A. AU - Loddenkemper, R. DO - 10.1378/chest.06-2728 KW - Adult Antitubercular Agents/therapeutic use Carrier State/diagnosis Cost-Benefit Analysis/statistics & numerical data False Positive Reactions Female Germany Humans Interferon-gamma/blood Isoniazid/therapeutic use Male Markov Chains Mass Screening/economics/methods Models, Theoretical Sensitivity and Specificity Tuberculin Test/economics/methods Tuberculosis/diagnosis/drug therapy N1 - LR: 20081121; JID: 0231335; 0 (Antitubercular Agents); 54-85-3 (Isoniazid); 82115-62-6 (Interferon-gamma); ppublish PY - 2007 RN - fulltext fulltext_1208 SN - 0012-3692; 0012-3692 SP - 1424-1434 ST - Cost-effectiveness of interferon-gamma release assay screening for latent tuberculosis infection treatment in Germany T2 - Chest TI - Cost-effectiveness of interferon-gamma release assay screening for latent tuberculosis infection treatment in Germany VL - 131 Y2 - May ID - 2500 ER - TY - JOUR AB - The aim of the present study was to assess the cost-effectiveness of the new T-SPOT.TB assay versus the tuberculin skin test (TST) for screening contacts for latent tuberculosis (TB) infection in Switzerland. Health and economic outcomes of isoniazid treatment of 20- and 40-yr-old close contacts were compared in a Markov model over a 20-yr period following screening with TST only (at three cut-off values) and T-SPOT.TB alone or in combination with the TST. T-SPOT.TB-based treatment was cost-effective at (Euro)11,621 and (Euro)23,692 per life-year-gained (LYG) in the younger and older age group, respectively. No TST-based programmes were cost-effective, except at a 15-mm cut-off in the younger group only, where the cost-effectiveness ((Euro)26,451.LYG(-1)) fell just below the willingness-to-pay threshold. Combination of the TST with T-SPOT.TB slightly reduced the total cost compared with the T-SPOT.TB alone by 4.4 and 5.0% in the younger and older groups respectively. The number of contacts treated to avoid one case of TB decreased from 50 (95% confidence interval 32-106) with the TST (10-mm cut-off) to 18 (95%CI 11-43) if T-SPOT.TB was used. Using T-SPOT.TB alone or in combination with the tuberculin skin test for screening of close contacts before latent tuberculosis infection treatment is highly cost-effective in reducing the disease burden of tuberculosis. AD - School of Public Health, University of Dusseldorf, Germany. Roland.Diel@uni-duesseldorf.de AN - 17504793 AU - Diel, R. AU - Wrighton-Smith, P. AU - Zellweger, J. P. DA - Aug DO - 10.1183/09031936.00145906 DP - Nlm ET - 05/17 J2 - The European respiratory journal : official journal of the European Society for Clinical Respiratory Physiology KW - Adult Antitubercular Agents/therapeutic use Carrier State Cost-Benefit Analysis Decision Support Techniques False Positive Reactions Female Humans Interferon-gamma/ blood Male Markov Chains Mass Screening/ economics/methods Probability Sensitivity and Specificity Software Switzerland/epidemiology Tuberculin Test/ economics/methods Tuberculosis/ diagnosis/ drug therapy/epidemiology LA - eng N1 - Diel, R Wrighton-Smith, P Zellweger, J-P Switzerland Eur Respir J. 2007 Aug;30(2):321-32. Epub 2007 May 15. PY - 2007 RN - fulltext fulltext_1208 SN - 0903-1936 (Print) 0903-1936 (Linking) SP - 321-32 ST - Cost-effectiveness of interferon-gamma release assay testing for the treatment of latent tuberculosis T2 - Eur Respir J TI - Cost-effectiveness of interferon-gamma release assay testing for the treatment of latent tuberculosis UR - http://erj.ersjournals.com/content/30/2/321.full.pdf VL - 30 ID - 6684 ER - TY - JOUR AB - Recognizing that tuberculosis (TB) is still the leading cause of human death from a curable infection, the international health community has set ambitious targets for disease control. One target is to eliminate TB by 2050; that is, to cut the annual incidence of new cases to less than 1 per million population. National TB control programmes are working to eliminate TB mainly by intensifying efforts to find and cure patients with active disease. Here, we use mathematical modelling to show that, while most TB patients can be cured with present drug regimens, the 2050 target is far more likely to be achieved with a combination of diagnostics, drugs and vaccines that can detect and treat both latent infection and active disease. We find that the coupling of control methods is particularly effective because treatments for latent infection and active disease act in synergy. This synergistic effect offers new perspectives on the cost-effectiveness of treating latent TB infection and the impact of possible new TB vaccines. Our results should be a stimulus to those who develop, manufacture and implement new technology for TB control, and to their financial donors. AD - HIV/AIDS, Tuberculosis and Malaria, World Health Organization, Avenue Appia 20, 1211 Geneva 27, Switzerland. dyec@who.int AN - 17690054 AU - Dye, C. AU - Williams, B. G. DA - Jun 6 DO - N502JJ12W45R6403 [pii] 10.1098/rsif.2007.1138 [doi] DP - Nlm ET - 08/11 KW - Antitubercular Agents/therapeutic use Computer Simulation Endemic Diseases Humans Models, Biological Tuberculosis/drug therapy/ prevention & control/transmission World Health LA - eng N1 - Dye, Christopher Williams, Brian G Research Support, Non-U.S. Gov't England Journal of the Royal Society, Interface / the Royal Society J R Soc Interface. 2008 Jun 6;5(23):653-62. PY - 2007 RN - fulltext fulltext_1208 SN - 1742-5689 (Print) 1742-5662 (Linking) SP - 653-62 ST - Eliminating human tuberculosis in the twenty-first century T2 - J R Soc Interface TI - Eliminating human tuberculosis in the twenty-first century UR - http://rsif.royalsocietypublishing.org/content/5/23/653.full.pdf VL - 5 ID - 2527 ER - TY - JOUR AN - 17502 AU - Eilers, P. H. C. AU - Borgdorff, M. W. KW - epidemiology mixture analysis models penalized likelihood risk of infection smoothing statistics N1 - TB Transmission, pathogenesis, and epidemiology Infection with tubercle bacilli Predict epi: risk of infection Risk of infection - models PY - 2007 RN - fulltext fulltext_1208 SP - 5444-5451 ST - Non-parametric log-concave mixtures T2 - Comp.Stat.Data Analysis TI - Non-parametric log-concave mixtures UR - file://C:\literature_pdf\rm17502.pdf VL - 51 ID - 2502 ER - TY - JOUR AB - OBJECTIVE: We undertook a decision analysis to evaluate the economic and health effects and incremental cost-effectiveness of using targeted tuberculin skin testing, compared with universal screening or no screening, before kindergarten. METHODS: We constructed a decision tree to determine the costs and clinical outcomes of using targeted testing compared with universal screening or no screening. Baseline estimates for input parameters were taken from the medical literature and from California health jurisdiction data. Sensitivity analyses were performed to determine plausible ranges of associated outcomes and costs. We surveyed California health jurisdictions to determine the prevalence of mandatory universal tuberculin skin testing. RESULTS: In our base-case scenario, the cost to prevent an additional case of tuberculosis by using targeted testing, compared with no screening, was $524,897. The cost to prevent an additional case by using universal screening, compared with targeted testing, was $671,398. The incremental cost of preventing a case through screening remained above $100,000 unless the prevalence of tuberculin skin testing positivity increased to >10%. More than 51% of children entering kindergarten in California live where tuberculin skin testing is mandatory. CONCLUSIONS: The cost to prevent a case of tuberculosis by using either universal screening or targeted testing of kindergarteners is high. If targeted testing replaced universal tuberculin skin testing in California, then $1.27 million savings per year would be generated for more cost-effective strategies to prevent tuberculosis. Improving the positive predictive value of the risk factor tool or applying it to groups with higher prevalence of latent tuberculosis would make its use more cost-effective. Universal tuberculin skin testing should be discontinued, and targeted testing should be considered only when the prevalence of risk factor positivity and the prevalence of tuberculin skin testing positivity among risk factor-positive individuals are high enough to meet acceptable thresholds for cost-effectiveness. AD - Department of Pediatrics, University of California San Francisco, 3333 California St, San Francisco, CA 94118, USA. flahermanv@peds.ucsf.edu AN - 17606566 AU - Flaherman, V. J. AU - Porco, T. C. AU - Marseille, E. AU - Royce, S. E. DA - Jul DO - 10.1542/peds.2006-2168 DP - Nlm ET - 07/04 J2 - Pediatrics KW - California Child Child, Preschool Cost-Benefit Analysis Costs and Cost Analysis Humans Mass Screening/economics Risk Factors Sensitivity and Specificity Tuberculin Test/ economics Tuberculosis/diagnosis/ economics/prevention & control LA - eng N1 - Flaherman, Valerie J Porco, Travis C Marseille, Elliot Royce, Sarah E KL2 RR024130/RR/NCRR NIH HHS/United States Research Support, N.I.H., Extramural United States Pediatrics. 2007 Jul;120(1):90-9. PY - 2007 RN - fulltext fulltext_1208 SN - 1098-4275 (Electronic) 0031-4005 (Linking) SP - 90-9 ST - Cost-effectiveness of alternative strategies for tuberculosis screening before kindergarten entry T2 - Pediatrics TI - Cost-effectiveness of alternative strategies for tuberculosis screening before kindergarten entry UR - http://pediatrics.aappublications.org/content/120/1/90.full.pdf VL - 120 ID - 2503 ER - TY - JOUR AB - One-third of the world population (approximately 2 billion individuals) is currently infected with Mycobacterium tuberculosis, the vast majority harboring a latent infection. As the risk of reactivation is around 10% in a lifetime, it follows that 200 million of these will eventually develop active pulmonary disease. Only therapeutic or post-exposure interventions can tame this vast reservoir of infection. Treatment of latent infections can reduce the risk of reactivation, and there is accumulating evidence that combination with post-exposure vaccines can reduce the risk of reinfection. Here we develop mathematical models to explore the potential of these post-exposure interventions to control tuberculosis on a global scale. Intensive programs targeting recent infections appear generally effective, but the benefit is potentially greater in intermediate prevalence scenarios. Extending these strategies to longer-term persistent infections appears more beneficial where prevalence is low. Finally, we consider that susceptibility to reinfection is altered by therapy, and explore its epidemiological consequences. When we assume that therapy reduces susceptibility to subsequent reinfection, catastrophic dynamics are observed. Thus, a bipolar outcome is obtained, where either small or large reductions in prevalence levels result, depending on the rate of detection and treatment of latent infections. By contrast, increased susceptibility after therapy may induce an increase in disease prevalence and does not lead to catastrophic dynamics. These potential outcomes are silent unless a widespread intervention is implemented. AD - Instituto Gulbenkian de Ciencia, Apartado 14, 2781-901 Oeiras Cedex, Portugal. ggomes@igc.gulbenkian.pt AN - 17669435 AU - Gomes, G. AU - Rodrigues, P. AU - Hilker, F. M. AU - Mantilla-Beniers, N. B. AU - Muehlen, M. AU - Cristina Paulo, A. AU - Medley, G. F. DA - Oct 21 DO - S0022-5193(07)00284-6 [pii] 10.1016/j.jtbi.2007.06.005 [doi] DP - Nlm ET - 08/03 KW - Antitubercular Agents/therapeutic use Carrier State/immunology Humans Models, Biological Recurrence/prevention & control Tuberculosis/ immunology/ prevention & control/transmission Tuberculosis Vaccines LA - eng N1 - Gabriela M Gomes, M Rodrigues, Paula Hilker, Frank M Mantilla-Beniers, Natalia B Muehlen, Marion Cristina Paulo, Ana Medley, Graham F Research Support, Non-U.S. Gov't Netherlands Journal of theoretical biology J Theor Biol. 2007 Oct 21;248(4):608-17. Epub 2007 Jul 4. PY - 2007 RN - fulltext fulltext_1208 SN - 0022-5193 (Print) 0022-5193 (Linking) SP - 608-17 ST - Implications of partial immunity on the prospects for tuberculosis control by post-exposure interventions T2 - J Theor Biol TI - Implications of partial immunity on the prospects for tuberculosis control by post-exposure interventions UR - http://ac.els-cdn.com/S0022519307002846/1-s2.0-S0022519307002846-main.pdf?_tid=5839d379ca81b25a7b73afd9055a8d60&acdnat=1345012345_79ffbc04fe99446b4f36cf19900f8c40 VL - 248 ID - 2504 ER - TY - JOUR AB - Isoniazid, administered as part of combination antituberculosis therapy, is responsible for most of the early bactericidal activity (EBA) of the regimen. However, the emergence of Mycobacterium tuberculosis resistance to isoniazid is a major problem. We examined the relationship between isoniazid exposure and M. tuberculosis microbial kill, as well as the emergence of resistance, in our in vitro pharmacodynamic model of tuberculosis. Since single-nucleotide polymorphisms of the N-acetyltransferase-2 gene lead to two different clearances of isoniazid from serum in patients, we simulated the isoniazid concentration-time profiles encountered in both slow and fast acetylators. Both microbial kill and the emergence of resistance during monotherapy were associated with the ratio of the area under the isoniazid concentration-time curve from 0 to 24 h (AUC(0-24)) to the isoniazid MIC. The time in mutant selection window hypothesis was rejected. Next, we utilized the in vitro relationship between the isoniazid AUC(0-24)/MIC ratio and microbial kill, the distributions of isoniazid clearance in populations with different percentages of slow and fast acetylators, and the distribution of isoniazid MICs for isonazid-susceptible M. tuberculosis clinical isolates in Monte Carlo simulations to calculate the EBA expected for approximately 10,000 patients treated with 300 mg of isoniazid. For those patient populations in which the proportion of fast acetylators and the isoniazid MICs were high, the average EBA of the standard dose was approximately 0.3 log(10) CFU/ml/day and was thus suboptimal. Our approach, which utilizes preclinical pharmacodynamics and the genetically determined multimodal distributions of serum clearances, is a preclinical tool that may be able to predict the EBAs of various doses of new antituberculosis drugs. AD - Division of Infectious Diseases, UT Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-9113, USA. Tawanda.Gumbo@UTSouthwestern.edu AN - 17438043 AU - Gumbo, T. AU - Louie, A. AU - Liu, W. AU - Brown, D. AU - Ambrose, P. G. AU - Bhavnani, S. M. AU - Drusano, G. L. DA - Jul DO - AAC.00185-07 [pii] 10.1128/AAC.00185-07 [doi] DP - Nlm ET - 04/18 KW - Antitubercular Agents/pharmacokinetics/ pharmacology Area Under Curve Colony Count, Microbial Computer Simulation Dose-Response Relationship, Drug Drug Resistance, Bacterial/genetics Ethnic Groups/ classification Humans Isoniazid/pharmacokinetics/ pharmacology Microbial Sensitivity Tests Models, Biological Monte Carlo Method Mutation Mycobacterium tuberculosis/ drug effects/genetics/isolation & purification Pharmacogenetics Time Factors L1 - internal-pdf://0062309846/Gumbo-2007-Isoniazid bactericidal activity and.pdf LA - eng N1 - Gumbo, Tawanda Louie, Arnold Liu, Weiguo Brown, David Ambrose, Paul G Bhavnani, Sujata M Drusano, George L Research Support, Non-U.S. Gov't United States Antimicrobial agents and chemotherapy Antimicrob Agents Chemother. 2007 Jul;51(7):2329-36. Epub 2007 Apr 16. PY - 2007 RN - fulltext fulltext_1208 SN - 0066-4804 (Print) 0066-4804 (Linking) SP - 2329-36 ST - Isoniazid bactericidal activity and resistance emergence: integrating pharmacodynamics and pharmacogenomics to predict efficacy in different ethnic populations T2 - Antimicrob Agents Chemother TI - Isoniazid bactericidal activity and resistance emergence: integrating pharmacodynamics and pharmacogenomics to predict efficacy in different ethnic populations UR - http://aac.asm.org/content/51/7/2329.full.pdf https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1913269/pdf/0185-07.pdf VL - 51 ID - 2505 ER - TY - JOUR AB - OBJECTIVE: To review the transmission models of tuberculosis in heterogeneous population. DATA SOURCES: The data used in this review were adopted mainly from the studies of models of tuberculosis reported from 1995 to 2006. STUDY SELECTION: Relevant literature on transmission models of tuberculosis in heterogeneous populations are referenced. RESULTS: Casual/random factors and genetic factors are the main reasons for epidemics of tuberculosis in recent years. Mass public transport is playing the primary role in casually close contact which can facilitate the transmission of tuberculosis. Genetic susceptibility not only varies endemic prevalence levels, but also drastically alters the effects of treatment for tuberculosis patients. Detailed studies further exhibit that casual contact and genetic factor are responsible for over 30% - 40% of the total new cases in recent years. The prevalence of tuberculosis could double (from 33% to 60%) if a genetically susceptible phenotype is present in only 30% of the population. And some challenges have emerged along with these exciting results. CONCLUSIONS: Casual/random contact, public transport and genetic susceptibility are responsible for most new tuberculosis cases and a wide variation in endemic tuberculosis levels between regions. Hence, the transmission model of tuberculosis in a heterogeneous population can provide more clues to underlying mechanism of tuberculosis transmission than in a homogeneous population. However, many challenges remain for us in understanding transmission of disease. AD - School of InformatioEineering, Beijing University of Posts and Telecommunications, Beijing 100876, China. AN - 17711744 AU - Jia, Z. W. AU - Li, X. W. AU - Feng, D. AU - Cao, W. C. DA - Aug 05 DP - NLM ET - 2007/08/23 IS - 15 J2 - Chinese medical journal KW - Cluster Analysis Genetic Predisposition to Disease Humans Models, Theoretical Tuberculosis/*transmission LA - eng N1 - Jia, Zhong-wei Li, Xiao-wen Feng, Dan Cao, Wu-chun Journal Article Research Support, Non-U.S. Gov't Review China Chin Med J (Engl). 2007 Aug 5;120(15):1360-5. PY - 2007 SN - 0366-6999 (Print) 0366-6999 SP - 1360-5 ST - Transmission models of tuberculosis in heterogeneous population T2 - Chin Med J (Engl) TI - Transmission models of tuberculosis in heterogeneous population VL - 120 ID - 2923 ER - TY - JOUR AB - This paper presents a mathematical model to evaluate the impact of different latent periods on the epidemic of tuberculosis. Analysis results show that the disease-free equilibrium P-0 is globally asymptotically stable and disease is eliminated from population if R-0 <= 1. However, the roof of stability of the unique endemic equilibrium P* is still a challege. Numerical simulation demonstrates that P* is globally asymptotically stable if R-0 > 1. AD - Beijing Inst Microbiol & Epidemiol, State Key Lab Pathogen & Biosecur, 20 Dong Da St,Fengtai Dist, Beijing 100071, Peoples R China Beijing Univ Posts & Telecommun, Beijing 100871, Peoples R China Chinese Acad Sci, Inst Remote Sensing Applicat, Beijing 100864, Peoples R China North Univ China, Taiyuan, Peoples R China AN - WOS:000250429200081 AU - Jia, Z. W. AU - Li, X. W. AU - Jin, Z. AU - Feng, D. AU - Cao, W. C. DO - 10.1109/Snpd.2007.63 KW - infection therapy LA - English N1 - Bgt70 Times Cited:0 Cited References Count:15 PY - 2007 SP - 422-+ ST - A model for tuberculosis with various latent periods T2 - Snpd 2007: Eighth Acis International Conference on Software Engineering, Artificial Intelligence, Networking, and Parallel/Distributed Computing, Vol 1, Proceedings TI - A model for tuberculosis with various latent periods UR - ://WOS:000250429200081 ID - 4842 ER - TY - JOUR AB - This paper considers an SEIT epidemic model that incorporates proportion recruitment and with vertical transmission. BY means of Lyapunov function and LaSalle's invariant set theorem, we proved the global asymptotical stable results of the disease-free equilibrium and the endenzic equilibrium with the help of numerical simulations. AD - North Univ China, Dept Math, Taiyuan 030051, Peoples R China Yuncheng Univ, Dept Math, Yuncheng 044000, Peoples R China AN - WOS:000250717100094 AU - Ma, C. AU - Zhang, F. Q. AU - Jin, Z. DO - 10.1109/Snpd.2007.337 KW - dynamics populations epidemic LA - English N1 - Bgu85 Times Cited:1 Cited References Count:15 PY - 2007 SP - 508-+ ST - Global stability of a tuberculosis model with vertical transmission T2 - Snpd 2007: Eighth Acis International Conference on Software Engineering, Artificial Intelligence, Networking, and Parallel/Distributed Computing, Vol 3, Proceedings TI - Global stability of a tuberculosis model with vertical transmission UR - ://WOS:000250717100094 ID - 4843 ER - TY - JOUR AB - The Global Plan to Stop TB 2006-2015 is a road map for policy-makers and managers of national programmes. It sets out the key actions needed to achieve the targets of the Millennium Development Goals relating to tuberculosis (T13): to halve the prevalence and deaths by 2015 relative to 1990 levels and to save 14 million lives. Developed by a broad coalition of partners, the plan presents a model approach combining interventions that can feasibly be supplied on the ground. The main areas of activity set out in the plan are: scaling up interventions to control tuberculosis; promoting the research and development of improved diagnostics, drugs and vaccines; and engaging in related activities for advocacy, communications and social mobilization. Scenarios for the planning process were developed; these looked at issues both globally and in seven epidemiological regions. The scenarios made ambitious but realistic assumptions about the pace of scale-up and implementation coverage of the activities. A mathematical model was used to estimate the impact of scaling up current interventions based on data from studies of tuberculosis biology and from experience with tuberculosis control in diverse settings. The estimated costs of the activities set out in the Global Plan were based on implementing interventions and researching and developing drugs, diagnostics and vaccines; these costs were US$ 56 billion over 10 years. When translated into cost per disability adjusted life year averted, these costs compare favourably with those of other public health interventions. This approach to planning for global tuberculosis control is a valuable example of developing plans to improve global health that has relevance for other health issues. AD - Koek, I WHO, Stop TB Dept, CH-1211 Geneva, Switzerland WHO, Stop TB Dept, CH-1211 Geneva, Switzerland WHO, Stop TB Dept, CH-1211 Geneva, Switzerland WHO, Dept Immunizat, CH-1211 Geneva, Switzerland WHO, Special Programme Res & Training Trop Dis, CH-1211 Geneva, Switzerland Stop TB Partnership, Working Grp New Drugs, New York, NY USA AN - ISI:000246790400008 AU - Maher, D. AU - Dye, C. AU - Floyd, K. AU - Pantoja, A. AU - Lonnroth, K. AU - Reid, A. AU - Nathanson, E. AU - Pennas, T. AU - Fruth, U. AU - Cunningham, J. AU - Ignatius, H. AU - Raviglione, M. C. AU - Koek, I. AU - Espinal, M. DA - May DO - Doi 10.2471/Blt.06.037820 J2 - B World Health Organ KW - public-health stop tb impact model LA - English N1 - 172FV Times Cited:31 Cited References Count:27 PY - 2007 RN - fulltext fulltext_1208 SN - 0042-9686 SP - 341-347 ST - Planning to improve global health: the next decade of tuberculosis control T2 - Bulletin of the World Health Organization TI - Planning to improve global health: the next decade of tuberculosis control UR - ://000246790400008http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2636650/pdf/06-037820.pdf VL - 85 ID - 2508 ER - TY - JOUR AB - The immune response to Mycobacterium tuberculosis (Mtb) infection is complex. Experimental evidence has revealed that tumor necrosis factor (TNF) plays a major role in host defense against Mtb in both active and latent phases of infection. TNF-neutralizing drugs used to treat inflammatory disorders have been reported to increase the risk of tuberculosis (TB), in accordance with animal studies. The present study takes a computational approach toward characterizing the role of TNF in protection against the tubercle bacillus in both active and latent infection. We extend our previous mathematical models to investigate the roles and production of soluble (sTNF) and transmembrane TNF (tmTNF). We analyze effects of anti-TNF therapy in virtual clinical trials (VCTs) by simulating two of the most commonly used therapies, anti-TNF antibody and TNF receptor fusion, predicting mechanisms that explain observed differences in TB reactivation rates. The major findings from this study are that bioavailability of TNF following anti-TNF therapy is the primary factor for causing reactivation of latent infection and that sTNF--even at very low levels--is essential for control of infection. Using a mathematical model, it is possible to distinguish mechanisms of action of the anti-TNF treatments and gain insights into the role of TNF in TB control and pathology. Our study suggests that a TNF-modulating agent could be developed that could balance the requirement for reduction of inflammation with the necessity to maintain resistance to infection and microbial diseases. Alternatively, the dose and timing of anti-TNF therapy could be modified. Anti-TNF therapy will likely lead to numerous incidents of primary TB if used in areas where exposure is likely. AD - Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA. AN - 17953477 AU - Marino, S. AU - Sud, D. AU - Plessner, H. AU - Lin, P. L. AU - Chan, J. AU - Flynn, J. L. AU - Kirschner, D. E. C2 - PMC2041971 DA - Oct DO - 10.1371/journal.pcbi.0030194 DP - NLM ET - 2007/10/24 IS - 10 J2 - PLoS computational biology KW - Animals Antitubercular Agents/*pharmacokinetics/therapeutic use Computational Biology/*methods Granuloma/metabolism Humans Models, Statistical Models, Theoretical Mycobacterium Infections/drug therapy Mycobacterium tuberculosis/metabolism Sensitivity and Specificity Signal Transduction T-Lymphocytes/drug effects/microbiology Tuberculosis/*drug therapy Tumor Necrosis Factor-alpha/antagonists & inhibitors/*metabolism L1 - internal-pdf://3820148719/Marino-2007-Differences in reactivation of tub.pdf LA - eng N1 - 1553-7358 Marino, Simeone Sud, Dhruv Plessner, Hillarie Lin, Philana Ling Chan, John Flynn, JoAnne L Kirschner, Denise E R01 HL071241/HL/NHLBI NIH HHS/United States HL68526/HL/NHLBI NIH HHS/United States R01 LM009027/LM/NLM NIH HHS/United States DAIT-BAA-05-10/PHS HHS/United States LMHL68526/PHS HHS/United States HL71241/HL/NHLBI NIH HHS/United States R01 HL106804/HL/NHLBI NIH HHS/United States R01 EB012579/EB/NIBIB NIH HHS/United States R01 HL068526/HL/NHLBI NIH HHS/United States Journal Article Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't United States PLoS Comput Biol. 2007 Oct;3(10):1909-24. Epub 2007 Aug 22. PY - 2007 SN - 1553-734x SP - 1909-24 ST - Differences in reactivation of tuberculosis induced from anti-TNF treatments are based on bioavailability in granulomatous tissue T2 - PLoS Comput Biol TI - Differences in reactivation of tuberculosis induced from anti-TNF treatments are based on bioavailability in granulomatous tissue UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2041971/pdf/pcbi.0030194.pdf VL - 3 ID - 2145 ER - TY - JOUR AB - SETTING: Rio de Janeiro, Brazil, is a middle-income setting with an estimated 1% adult human immunodeficiency virus (HIV) seroprevalence. OBJECTIVE: To examine the cost-effectiveness of DOTS in Rio de Janeiro. DESIGN: Cost-effectiveness analysis based on cost data and an epidemiological model based on programmatic outcomes from the Health Department in Rio de Janeiro, cost data from the retail market sector and epidemiological data from published studies. RESULTS: The 10-year cost of a tuberculosis program treating a population of 262 000 based on self-administered therapy (SAT) was estimated to be $580 271 compared to $1047 886 for DOTS. The largest portion of the DOTS budget was for staff costs and costs incurred by patients, both at 28%. For SAT, the largest percentage of the budget was allocated to medication costs, at 34%. Upgrading from SAT to DOTS averted 1558 cases of tuberculosis (TB, uncertainty range [UR] 1418-1704) and 143 TB deaths (UR 131-155). The incremental cost effectiveness ratio (ICER) for DOTS was $300 per case averted (UR $289-$312) and $3270 per death averted (UR $3123-$3435). In terms of disability adjusted life years (DALYs), DOTS saved 5426 DALYs (UR 4908-5961). The ICER for DOTS was $86 per DALY saved (UR $74-$100). CONCLUSIONS: DOTS is a highly cost-effective intervention in Brazil. AD - Johns Hopkins School of Medicine, Baltimore, USA. mohanci@yahoo.com AN - 17217126 AU - Mohan, C. I. AU - Bishai, D. AU - Cavalcante, S. AU - Chaisson, R. E. DA - Jan IS - 1 KW - Antitubercular Agents/*therapeutic use Brazil/epidemiology Cost-Benefit Analysis Directly Observed Therapy/*economics Female HIV Seropositivity/epidemiology Humans Male Prevalence Tuberculosis/*drug therapy/epidemiology Urban Population N1 - Mohan, C I Bishai, D Cavalcante, S Chaisson, R E eng 45432/PHS HHS/ Research Support, N.I.H., Extramural Research Support, U.S. Gov't, Non-P.H.S. France 2007/01/16 09:00 Int J Tuberc Lung Dis. 2007 Jan;11(1):27-32. PY - 2007 SN - 1027-3719 (Print) 1027-3719 (Linking) SP - 27-32 ST - The cost-effectiveness of DOTS in urban Brazil T2 - Int J Tuberc Lung Dis TI - The cost-effectiveness of DOTS in urban Brazil UR - https://www.ncbi.nlm.nih.gov/pubmed/17217126 VL - 11 ID - 2256 ER - TY - JOUR AB - We apply the techniques of Lie's symmetry analysis to a caricature of the simplified multistrain model of Castillo-Chavez and Feng [C. Castillo-Chavez, Z. Feng, To treat or not to treat: The case of tuberculosis, J. Math. Biol. 35 (1997) 629-656] for the transmission of tuberculosis and the coupled two-stream vector-based model of Feng and Velasco-Hernandez [Z. Feng, JX Velasco-Hernandez, Competitive exclusion in a vector-host model for the dengue fever, J. Math. Biol. 35 (1997) 523-544] to identify the combinations of parameters which lead to the existence of nontrivial symmetries. In particular we identify those combinations which lead to the possibility of the linearization of the system and provide the corresponding solutions. Many instances of additional symmetry are analyzed. (c) 2007 Elsevier Inc. All rights reserved. AD - Univ Perugia, Dipartimento Matemat & Informat, I-06123 Perugia, Italy. Univ KwaZulu Natal, Sch Math Sci, ZA-4000 Durban, South Africa. Nucci, MC (reprint author), Univ Perugia, Dipartimento Matemat & Informat, I-06123 Perugia, Italy. nucci@unipg.it; leachp@ukzn.ac.za AN - WOS:000247325900029 AU - Nucci, M. C. AU - Leach, P. G. L. DA - Sep DO - 10.1016/j.jmaa.2007.02.061 IS - 1 J2 - J. Math. Anal. Appl. KW - Lie group analysis mathematical epidemiology configurational invariants Mathematics LA - English M3 - Article N1 - ISI Document Delivery No.: 179YG Times Cited: 8 Cited Reference Count: 16 Nucci, M. C. Leach, P. G. L. Nucci, Maria Clara/B-3588-2012 Nucci, Maria Clara/0000-0003-1453-0988 8 0 1 Academic press inc elsevier science San diego PY - 2007 SN - 0022-247X SP - 430-449 ST - Lie integrable cases of the simplified multistrain/two-stream model for tuberculosis and dengue fever T2 - Journal of Mathematical Analysis and Applications TI - Lie integrable cases of the simplified multistrain/two-stream model for tuberculosis and dengue fever UR - ://WOS:000247325900029 VL - 333 ID - 6041 ER - TY - JOUR AB - This paper presents mathematical models for tuberculosis and its dynamics under the implementation of the direct observation therapy strategy (DOTS) in Nigeria. The models establish conditions for the eradication of tuberculosis in Nigeria based on the fraction of detected infectious individuals placed under DOTS for treatment. Both numerical and qualitative analysis of the models were carried out and the effect of the fraction of detected cases of active TB on the various epidemiological classes is investigated. The results showed that, provided that the fraction of detected infectious individuals exceeded a critical value, there exists a globally stable disease free equilibrium. However, if this critical detection level is not reached, the disease-free equilibrium will be unstable even with the very high probability successful treatment under DOTS. The results showed that DOTS expansion in Nigeria must include significant increase in the detection rate of infectious individuals; otherwise the effect in reducing the incidence in Nigeria will not be achieved disregarding the tremendous efforts in any other direction, and the huge number of undetected cases will make DOTS insignificant with respect to tuberculosis control. AD - Univ Benin, Dept Math, Benin, Edo State, Nigeria Univ Limerick, Dept Math & Stat, MACSI, Limerick, Ireland AN - WOS:000207833200006 AU - Okuonghae, D. AU - Korobeinikov, A. DO - 10.1051/mmnp:2008013 IS - 1 J2 - Math Model Nat Pheno KW - tuberculosis mathematical model dots prevention and control case detection global stability basic reproduction number LA - English N1 - V15wx Times Cited:7 Cited References Count:33 PY - 2007 SN - 0973-5348 SP - 113-128 ST - Dynamics of Tuberculosis: The effect of Direct Observation Therapy Strategy (DOTS) in Nigeria T2 - Mathematical Modelling of Natural Phenomena TI - Dynamics of Tuberculosis: The effect of Direct Observation Therapy Strategy (DOTS) in Nigeria UR - ://WOS:000207833200006 VL - 2 ID - 4844 ER - TY - JOUR AB - There is increasing recognition that reinfection is an important component of TB transmission. Moreover, it has been shown that partial immunity has significant epidemiological consequences, particularly in what concerns disease prevalence and effectiveness of control measures. We address the problem of drug resistance as a competition between two types of strains of Mycobacterium tuberculosis: those that are sensitive to anti-tuberculosis drugs and those that are resistant. Our objective is to characterise the role of reinfection in the transmission of drug-resistant tuberculosis. The long-term behaviour of our model reflects how reinfection modifies the conditions for coexistence of sensitive and resistant strains. This sets the scene for discussing how strain prevalence is affected by different control strategies. It is shown that intervention effectiveness is highly sensitive to the baseline epidemiological setting. (c) 2006 Elsevier Inc. All rights reserved. AD - Inst Gulbenkian Ciencias, P-2781901 Oeiras, Portugal. Univ Nova Lisboa, Fac Ciencias & Tecnol, P-2825114 Caparica, Portugal. Fac Ciencias Lisboa, P-1649003 Lisbon, Portugal. Ctr Matemat Aplicacoes Fundamentais, P-1649003 Lisbon, Portugal. Rodrigues, P (reprint author), Inst Gulbenkian Ciencias, Apartado 14, P-2781901 Oeiras, Portugal. pcpr@igc.gulbenkian.pt; ggomes@igc.gulbenkian.pt; carlota@ptmat.fc.ul.pt AN - WOS:000244907800007 AU - Rodrigues, P. AU - Gomes, M. G. M. AU - Rebelo, C. DA - Mar DO - 10.1016/j.tpb.2006.10.004 IS - 2 J2 - Theor. Popul. Biol. KW - reinfection drug resistance tuberculosis control strategies coexistence stability mathematical models mycobacterium-tuberculosis antibiotic-resistance threshold transmission strategies framework emergence epidemics dynamics fitness Environmental Sciences & Ecology Evolutionary Biology Genetics & Heredity L1 - internal-pdf://2378446066/1-s2.0-S0040580906001316-main.pdf LA - English M3 - Article N1 - ISI Document Delivery No.: 146AV Times Cited: 38 Cited Reference Count: 32 Rodrigues, Paula Gomes, M. Gabriela M. Rebelo, Carlota Gomes, Gabriela/H-7218-2014; Rebelo, Carlota/M-2582-2015 Gomes, Gabriela/0000-0002-1454-4979; Rebelo, Carlota/0000-0001-5818-8892; Paticio, Paula/0000-0001-6766-4336 39 1 10 Academic press inc elsevier science San diego PY - 2007 SN - 0040-5809 SP - 196-212 ST - Drug resistance in tuberculosis - a reinfection model T2 - Theoretical Population Biology TI - Drug resistance in tuberculosis - a reinfection model UR - ://WOS:000244907800007 VL - 71 ID - 6073 ER - TY - JOUR AB - A combination of continuous and categorical tests, none of which is a gold standard, is often available for classification of subject status in epidemiologic studies. For example, tuberculosis (TB) molecular epidemiology uses select mycobacterial DNA sequences to provide clues about which cases of active TB are likely clustered, implying recent transmission between these cases, versus reactivation of previously acquired infection. The proportion of recently transmitted cases is important to public health, as different control methods are implemented as transmission rates increase. Standard typing methods include IS6110 restriction fragment length polymorphism (IS6110 RFLP), but recently developed polymerase chain reaction based genotyping modalities, including mycobacterial interspersed repetitive unit-variable-number tandem repeat and spoligotyping provide quicker results. In addition, it has recently been suggested that results from IS6110 RFLP can be used to create a continuous measure of genetic relatedness, called the nearest genetic distance. Whichever method is used, estimation of cluster rates is rendered difficult by the lack of a gold standard method for classifying cases as clustered or not. Since many of these methods are relatively new, their properties have not been extensively investigated. Misclassification errors subsequently lead to sub-optimal estimation of risk factors for clustering. Here we show how Bayesian latent class models can be used in such situations, for example to simultaneously analyse Mycobacterium tuberculosis DNA data from all three of the above methods. Using the data collected at the Public Health Unit in Montreal, we estimate the proportion of clustered cases and the operating characteristics of each method using information from all three methods combined, including both continuous and dichotomous measures from IS6110 RFLP. A misclassification-adjusted regression model provides estimates of the effects of risk factors on the clustering probabilities. We also discuss how one must carefully interpret any inferences that arise from a combination of continuous and dichotomous tests. AD - Department of Epidemiology and Biostatistics, McGill University, 1020 Pine Avenue West, Montreal, Que., Canada H3A 1A2. AN - 17437254 AU - Scott, A. N. AU - Joseph, L. AU - Belisle, P. AU - Behr, M. A. AU - Schwartzman, K. DA - Jan 15 DO - 10.1002/sim.2899 [doi] DP - Nlm ET - 04/18 KW - Analysis of Variance Bayes Theorem Cluster Analysis DNA Fingerprinting Female Humans Male Molecular Epidemiology/ methods Mycobacterium tuberculosis/ genetics Tuberculosis/ epidemiology/ microbiology LA - eng N1 - Scott, Allison N Joseph, Lawrence Belisle, Patrick Behr, Marcel A Schwartzman, Kevin England Statistics in medicine Stat Med. 2008 Jan 15;27(1):140-56. PY - 2007 RN - fulltext fulltext_1208 SN - 0277-6715 (Print) 0277-6715 (Linking) SP - 140-56 ST - Bayesian modelling of tuberculosis clustering from DNA fingerprint data T2 - Stat Med TI - Bayesian modelling of tuberculosis clustering from DNA fingerprint data UR - http://onlinelibrary.wiley.com.ez.lshtm.ac.uk/store/10.1002/sim.2899/asset/2899_ftp.pdf?v=1&t=h5w29req&s=302abd98afe554aacc48977400af05ce6136728f VL - 27 ID - 2543 ER - TY - JOUR AN - 17660 AU - Shrestha, R. K. AU - Mugisha, B. AU - Bunnell, R. AU - Mermin, J. AU - Odeke, R. AU - Madra, P. AU - Hitimana-Lukanika, C. AU - Adatu-Engwau, F. AU - Blandford, J. M. KW - adults cost effectiveness decision analysis HIV prevention tuberculosis Uganda N1 - TB Periodical PY - 2007 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SP - 747-754 ST - Cost-utility of tuberculosis prevention among HIV-infected adults in Kampala, Uganda T2 - Int.J.Tuberc.Lung Dis. TI - Cost-utility of tuberculosis prevention among HIV-infected adults in Kampala, Uganda UR - file://C:\literature_pdf\rm17660.pdf VL - 11 ID - 2509 ER - TY - JOUR AB - Recent new methods in Bayesian simulation have provided ways of evaluating posterior distributions in the presence of analytically or computationally intractable likelihood functions. Despite representing a substantial methodological advance, existing methods based on rejection sampling or Markov chain Monte Carlo can be highly inefficient and accordingly require far more iterations than may be practical to implement. Here we propose a sequential Monte Carlo sampler that convincingly overcomes these inefficiencies. We demonstrate its implementation through an epidemiological study of the transmission rate of tuberculosis. AD - School of Mathematics and Statistics, University of New South Wales, Sydney, NSW 2052, Australia. scott.sisson@unsw.edu.au AN - 17264216 AU - Sisson, S. A. AU - Fan, Y. AU - Tanaka, M. M. DA - Feb 6 DO - 0607208104 [pii] 10.1073/pnas.0607208104 [doi] DP - Nlm ET - 02/01 KW - Algorithms Animals Bayes Theorem Computer Simulation/statistics & numerical data Humans Likelihood Functions Models, Statistical Monte Carlo Method Tuberculosis/epidemiology/transmission LA - eng N1 - Sisson, S A Fan, Y Tanaka, Mark M Research Support, Non-U.S. Gov't United States Proceedings of the National Academy of Sciences of the United States of America Proc Natl Acad Sci U S A. 2007 Feb 6;104(6):1760-5. Epub 2007 Jan 30. PY - 2007 RN - fulltext fulltext_1208 SN - 0027-8424 (Print) 0027-8424 (Linking) SP - 1760-5 ST - Sequential Monte Carlo without likelihoods T2 - Proc Natl Acad Sci U S A TI - Sequential Monte Carlo without likelihoods UR - http://www.pnas.org/content/104/6/1760.full.pdf VL - 104 ID - 2510 ER - TY - JOUR AB - Background: Tuberculosis ( TB) remains a major cause of mortality in developing countries, and in these countries diabetes prevalence is increasing rapidly. Diabetes increases the risk of TB. Our aim was to assess the potential impact of diabetes as a risk factor for incident pulmonary tuberculosis, using India as an example. Methods: We constructed an epidemiological model using data on tuberculosis incidence, diabetes prevalence, population structure, and relative risk of tuberculosis associated with diabetes. We evaluated the contribution made by diabetes to both tuberculosis incidence, and to the difference between tuberculosis incidence in urban and rural areas. Results: In India in 2000 there were an estimated 20.7 million adults with diabetes, and 900,000 incident adult cases of pulmonary tuberculosis. Our calculations suggest that diabetes accounts for 14.8% ( uncertainty range 7.1% to 23.8%) of pulmonary tuberculosis and 20.2% ( 8.3% to 41.9%) of smear- positive ( i. e. infectious) tuberculosis. We estimate that the increased diabetes prevalence in urban areas is associated with a 15.2% greater smear- positive tuberculosis incidence in urban than rural areas - over a fifth of the estimated total difference. Conclusion: Diabetes makes a substantial contribution to the burden of incident tuberculosis in India, and the association is particularly strong for the infectious form of tuberculosis. The current diabetes epidemic may lead to a resurgence of tuberculosis in endemic regions, especially in urban areas. This potentially carries a risk of global spread with serious implications for tuberculosis control and the achievement of the United Nations Millennium Development Goals. AD - Unwin, N Univ Newcastle Upon Tyne, Inst Hlth & Soc, Newcastle Upon Tyne NE1 7RU, Tyne & Wear, England Univ Newcastle Upon Tyne, Inst Hlth & Soc, Newcastle Upon Tyne NE1 7RU, Tyne & Wear, England Univ Newcastle Upon Tyne, Inst Hlth & Soc, Newcastle Upon Tyne NE1 7RU, Tyne & Wear, England MRC, Epidemiol Unit, Cambridge, England WHO, Dept Chron Dis & Hlth Promot, CH-1211 Geneva, Switzerland AN - ISI:000250030800001 AU - Stevenson, C. R. AU - Forouhi, N. G. AU - Roglic, G. AU - Williams, B. G. AU - Lauer, J. A. AU - Dye, C. AU - Unwin, N. DA - Sep 6 DO - Artn 234 Doi 10.1186/1471-2458-7-234 J2 - Bmc Public Health KW - impaired glucose-tolerance temporal-changes southern india prevalence population burden risk LA - English N1 - 218QU Times Cited:46 Cited References Count:33 PY - 2007 RN - fulltext fulltext_1208 SN - 1471-2458 ST - Diabetes and tuberculosis: the impact of the diabetes epidemic on tuberculosis incidence T2 - Bmc Public Health TI - Diabetes and tuberculosis: the impact of the diabetes epidemic on tuberculosis incidence UR - ://000250030800001http://www.biomedcentral.com/1471-2458/7/234 VL - 7 ID - 2512 ER - TY - JOUR AB - BACKGROUND: In many communities where TB occurs at high incidence, the major force driving the epidemic is transmission. It is plausible that the typical long delay from the onset of infectious disease to diagnosis and commencement of treatment is almost certainly the major factor contributing to the high rate of transmission. METHODOLOGY/PRINCIPAL FINDINGS: This study is confined to communities which are epidemiologically relatively isolated and which have low HIV incidence. The consequences of delays to diagnosis are analyzed and the existence of a threshold delay value is demonstrated. It is shown that unless a sufficient number of cases are detected before this threshold, the epidemic will escalate. The method used for the analysis avoids the standard computer integration of systems of differential equations since the intention is to present a line of reasoning that reveals the essential dynamics of an epidemic in an intuitively clear way that is nevertheless quantitatively realistic. CONCLUSIONS/SIGNIFICANCE: The analysis presented here shows that typical delays to diagnosis present a major obstacle to the control of a TB epidemic. Control can be achieved by optimizing the rapid identification of TB cases together with measures to increase the threshold value. A calculated and aggressive program is therefore necessary in order to bring about a reduction in the prevalence of TB in a community by decreasing the time to diagnosis in all its ramifications. Intervention strategies to increase the threshold value relative to the time to diagnosis and which thereby decrease disease incidence are discussed. AD - Division of Molecular Biology and Human Genetics, MRC Center for Molecular and Cellular Biology, Faculty of Health Sciences, Stellenbosch University, Cape Town, Western Cape, Republic of South Africa. AN - 17712405 AU - Uys, P. W. AU - Warren, R. M. AU - van Helden, P. D. DO - 10.1371/journal.pone.0000757 ET - 08/23 J2 - PloS one KW - Disease Susceptibility HIV Infections/epidemiology Humans Mycobacterium tuberculosis/pathogenicity South Africa/epidemiology Time Factors Tuberculosis, Pulmonary/*diagnosis/*epidemiology/transmission LA - eng M3 - Research Support, Non-U.S. Gov't N1 - Uys, Pieter W Warren, Robin M van Helden, Paul D PLoS One. 2007 Aug 22;2(8):e757. PY - 2007 SN - 1932-6203 (Electronic) 1932-6203 (Linking) SP - e757 ST - A threshold value for the time delay to TB diagnosis T2 - PLoS One TI - A threshold value for the time delay to TB diagnosis UR - http://www.ncbi.nlm.nih.gov/pubmed/17712405 VL - 2 ID - 2513 ER - TY - JOUR AB - Over 50% of the global burden of tuberculosis occurs in South East Asia and the Western Pacific. Since 1950, notification rates in high-income countries in these settings have declined slowly and have remained over ten-fold greater than those in Western populations. The reasons for the slow decline are poorly understood. Using an age-structured model describing the incidence of Mycobacterium tuberculosis infection and disease applied to notification data from Hong Kong, we illustrate that in Hong Kong, a high prevalence of M. tuberculosis infection among older individuals and a high risk of disease through reactivation (e.g. up to 17-fold greater than that estimated for infected males in the United Kingdom) may explain this slow decline. If this feature of the epidemiology of tuberculosis is widespread, the WHO directly observed treatment short-course (DOTS) strategy may have a smaller impact in Asia in the short term than has been implied by recent predictions, all of which have been based on disease risk estimates derived from Western Europe. As a result, it may be difficult to meet the targets for tuberculosis control, which have been prescribed by the UN Millennium Development Goals. AD - Modelling and Economics Unit, Health Protection Agency Centre for Infections, Colindale, London, UK. emilia.vynnycky@hpa.org.uk AN - 17678555 AU - Vynnycky, E. AU - Borgdorff, M. W. AU - Leung, C. C. AU - Tam, C. M. AU - Fine, P. E. DA - Jul DO - S0950268807008552 [pii] 10.1017/S0950268807008552 [doi] DP - Nlm ET - 08/07 KW - Adult Age Factors Aged Communicable Disease Control/methods Hong Kong/epidemiology Humans Incidence Male Middle Aged Recurrence Risk Factors Tuberculosis/ epidemiology LA - eng N1 - Vynnycky, E Borgdorff, M W Leung, C C Tam, C M Fine, P E M Medical Research Council/United Kingdom Research Support, Non-U.S. Gov't England Epidemiology and infection Epidemiol Infect. 2008 Jul;136(7):943-52. Epub 2007 Aug 3. PY - 2007 RN - fulltext fulltext_1208 SN - 0950-2688 (Print) 0950-2688 (Linking) SP - 943-52 ST - Limited impact of tuberculosis control in Hong Kong: attributable to high risks of reactivation disease T2 - Epidemiol Infect TI - Limited impact of tuberculosis control in Hong Kong: attributable to high risks of reactivation disease UR - http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=1872696 VL - 136 ID - 2547 ER - TY - JOUR AB - BACKGROUND: Resistance to commonly used antituberculosis drugs is emerging worldwide. Conventional drug-susceptibility testing (DST) methods are slow and demanding. Alternative, rapid DST methods would permit the early detection of drug resistance and, in turn, arrest tuberculosis transmission. METHODS: A cost-effectiveness analysis of 5 DST methods was performed in the context of a clinical trial that compared rapid with conventional DST methods. The methods under investigation were direct phage-replication assay (FASTPlaque-Response; Biotech), direct amplification and reverse hybridization of the rpoB gene (INNO-LiPA; Innogenetics), indirect colorimetric minimum inhibitory concentration assay (MTT; ICN Biomedicals), and direct proportion method on Lowenstein-Jensen medium. These were compared with the widely used indirect proportion method on Lowenstein-Jensen medium. RESULTS: All alternative DST methods were found to be cost-effective, compared with other health care interventions. DST methods also generate substantial cost savings in settings of high prevalence of multidrug-resistant tuberculosis. Excluding the effects of transmission, the direct proportion method on Lowenstein-Jensen medium was the most cost-effective alternative DST method for patient groups with prevalences of multidrug-resistant tuberculosis of 2%, 5%, 20%, and 50% (cost in US$2004, $94, $36, $8, and $2 per disability-adjusted life year, respectively). CONCLUSION: Alternative, rapid methods for DST are cost-effective and should be considered for use by national tuberculosis programs in middle-income countries. AD - Instituto de Medicina Tropical Alexander Von Humboldt, Lima, Peru. AN - 18636955 AU - Acuna-Villaorduna, C. AU - Vassall, A. AU - Henostroza, G. AU - Seas, C. AU - Guerra, H. AU - Vasquez, L. AU - Morcillo, N. AU - Saravia, J. AU - O'Brien, R. AU - Perkins, M. D. AU - Cunningham, J. AU - Llanos-Zavalaga, L. AU - Gotuzzo, E. DA - Aug 15 DO - 10.1086/590010 ET - 07/19 KW - Antitubercular Agents/*pharmacology Bacterial Proteins/genetics Colorimetry Cost-Benefit Analysis *Drug Resistance, Multiple, Bacterial Gene Amplification Humans Income/classification Microbial Sensitivity Tests/economics/methods Mycobacteriophages/physiology Mycobacterium tuberculosis/*drug effects/genetics/growth & development Nucleic Acid Hybridization Peru Quality-Adjusted Life Years Reagent Kits, Diagnostic Sensitivity and Specificity Time Factors Tuberculosis, Multidrug-Resistant/*diagnosis/epidemiology/microbiology Tuberculosis, Pulmonary/diagnosis/epidemiology/microbiology L1 - internal-pdf://2381178956/Acuna-Villaordu-2008-Cost-effectiveness analys.pdf LA - eng N1 - Acuna-Villaorduna, Carlos Vassall, Anna Henostroza, German Seas, Carlos Guerra, Humberto Vasquez, Lucy Morcillo, Nora Saravia, Juan O'Brien, Richard Perkins, Mark D Cunningham, Jane Llanos-Zavalaga, Luis Gotuzzo, Eduardo Clinical Trial, Phase III Research Support, Non-U.S. Gov't United States Clinical infectious diseases : an official publication of the Infectious Diseases Society of America Clin Infect Dis. 2008 Aug 15;47(4):487-95. PY - 2008 RN - fulltext fulltext_1208 SN - 1537-6591 (Electronic) 1058-4838 (Linking) SP - 487-95 ST - Cost-effectiveness analysis of introduction of rapid, alternative methods to identify multidrug-resistant tuberculosis in middle-income countries T2 - Clin Infect Dis TI - Cost-effectiveness analysis of introduction of rapid, alternative methods to identify multidrug-resistant tuberculosis in middle-income countries UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=18636955http://www.journals.uchicago.edu/doi/pdf/10.1086/590010http://cid.oxfordjournals.org/content/47/4/487.full.pdf https://watermark.silverchair.com/47-4-487.pdf?token=AQECAHi208BE49Ooan9kkhW_Ercy7Dm3ZL_9Cf3qfKAc485ysgAAAckwggHFBgkqhkiG9w0BBwagggG2MIIBsgIBADCCAasGCSqGSIb3DQEHATAeBglghkgBZQMEAS4wEQQMWZ-80ve7n9SxLa_YAgEQgIIBfC7za9ITklwoc9o8BLCv_eoI-rR-kEBW0qBov1QDuNaWTlJ8PZUpnJYBzfBwSTKjlRHzJ8QNGXxVIRhXQgqNaBwQxaH8ZHnyg5BPVxAh-K9BBUbCu1n8u0BM4spC-d8-aSrUzKwlaZA19olwd9mgzlBWT8BQqmzX3DWB-Upbkkjfua0T7bM9SPgi66l89VVGEFVA4DHuIdY0QBETrmOmuToX2OoV6JnGFNqP9C_mHbtHMatno9yGgxn1RPg6d8DhpwjCNHJFJG11e7VAJnIOiA4C4Vz1_xj06fXdf-SZ7w4B8fLSgo1Z3uq-5Z8mPJNccltC3l5N3yzAjsA_EKCYwsEsHUFzgAsj_HMiADENRFLiXiyryrzUfxJJBG70_sS8GHty20xbnehXSF9O86lLgpHI7BhfVUfYJ1rKC8pczNQ477eKgOepN-LcDohQNAiRe1uI5de7ZQhFRtxfpAaOc_QLKboDqKqkSdJuMuAOSvO-it1lo8liYxmJOHfn VL - 47 ID - 2514 ER - TY - JOUR AB - We present a simple mathematical model with six compartments for the interaction between HIV and TB epidemics. Using data from a township near Cape Town, South Africa, where the prevalence of HIV is above 20% and where the TB notification rate is close to 2,000 per 100,000 per year, we estimate some of the model parameters and study how various control measures might change the course of these epidemics. Condom promotion, increased TB detection and TB preventive therapy have a clear positive effect. The impact of antiretroviral therapy on the incidence of HIV is unclear and depends on the extent to which it reduces sexual transmission. However, our analysis suggests that it will greatly reduce the TB notification rate. AD - Institut de Recherche pour le Developpement, 32 avenue Henri Varagnat, 93143 Bondy, France. bacaer@bondy.ird.fr AN - 18414866 AU - Bacaer, N. AU - Ouifki, R. AU - Pretorius, C. AU - Wood, R. AU - Williams, B. DA - Oct DO - 10.1007/s00285-008-0177-z ET - 04/17 KW - Antiretroviral Therapy, Highly Active Antitubercular Agents/therapeutic use Comorbidity Condoms Disease Notification Disease Outbreaks/prevention & control Disease Transmission, Infectious/prevention & control HIV Infections/drug therapy/*epidemiology Humans Isoniazid/therapeutic use *Models, Biological Prevalence South Africa/epidemiology Tuberculosis/drug therapy/*epidemiology LA - eng N1 - Bacaer, Nicolas Ouifki, Rachid Pretorius, Carel Wood, Robin Williams, Brian Germany Journal of mathematical biology J Math Biol. 2008 Oct;57(4):557-93. Epub 2008 Apr 15. PY - 2008 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 0303-6812 (Print) 0303-6812 (Linking) SP - 557-93 ST - Modeling the joint epidemics of TB and HIV in a South African township T2 - J Math Biol TI - Modeling the joint epidemics of TB and HIV in a South African township UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=18414866http://www.springerlink.com/content/b7242x4625711ug8/fulltext.pdf VL - 57 ID - 2515 ER - TY - JOUR AB - Extensively drug-resistant tuberculosis (XDR TB) has emerged as a threat to TB control efforts in several high-burden areas, generating international concern. XDR TB is now found in every region of the world, but appears most worrisome in the context of HIV and in resource-limited settings with congregate hospital wards. Here, we examine the emergence and transmission dynamics of the disease, incorporating the mathematical modelling literature related to airborne infection and epidemiological studies related to the operations of TB control programmes in resource-limited settings. We find that while XDR TB may present many challenges in the setting of resource constraints, the central problems highlighted by the emergence of XDR TB are those that have plagued TB programmes for years. These include a slow rate of case detection that permits prolonged infectiousness, the threat of airborne infection in enclosed spaces, the problem of inadequate treatment delivery and treatment completion, and the need to develop health systems that can address the combination of TB and poverty. Mathematical models of TB transmission shed light on the idea that community-based therapy and rapid detection systems may be beneficial in resource-limited settings, while congregate hospital wards are sites for major structural reform. AU - Basu, S. AU - Galvani, A. P. DO - 10.1017/S0950268808000964 10.1017/S0950268808000964. Epub 2008 Jul 7. ET - 07/09 IS - 12 KW - *Models, Theoretical Extensively Drug-Resistant Tuberculosis/epidemiolo Humans Rural Health South Africa/epidemiology control/*transmission L1 - internal-pdf://2730768699/Basu-2008-The transmission and control of XDR.pdf LA - eng PY - 2008 SN - 0950-2688 (Print) 0950-2688 (Linking) SP - 1585-1598 ST - The transmission and control of XDR TB in South Africa: an operations research and mathematical modelling approach T2 - Epidemiol Infect TI - The transmission and control of XDR TB in South Africa: an operations research and mathematical modelling approach UR - http://www.ncbi.nlm.nih.gov/pubmed/18606028 http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=2634260 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/3CA94C1FC0E08456FCFF953B638F295C/S0950268808000964a.pdf/div-class-title-the-transmission-and-control-of-xdr-tb-in-south-africa-an-operations-research-and-mathematical-modelling-approach-div.pdf VL - 136 ID - 3919 ER - TY - JOUR AB - BACKGROUND: Emerging research suggests that genetically distinct strains of Mycobacterium tuberculosis may modulate the immune system differently. This may be of importance in high-burden settings where > or =1 genetic group of M. tuberculosis confers significant morbidity. METHODS: A dynamic mathematical model was constructed to evaluate how different degrees of cross-immunity among M. tuberculosis groups could affect epidemics of drug-resistant tuberculosis (TB). RESULTS: Simulated populations with immunogenically distinct TB strain groups experienced a heightened risk of drug-resistant TB, compared with populations without such strain diversity, even when the same rates of case detection and treatment success were achieved. The highest risks of infection were observed in populations in which HIV was prevalent. Drug-resistant strains with very low transmission fitness could still propagate in environments with reduced cross-immunity among different strain groups, even after common targets for case detection and treatment success are reached. CONCLUSIONS: It is possible that the propagation of drug-resistant strains could depend not only on the rate of development of resistance and the fitness of the drug-resistant strains but, also, on the diversity of the strains in the region. The risk of infection with drug-resistant strains could be amplified in locations where there is reduced cross-immunity between originating strain groups. This amplification may be most profound during the first few decades of TB treatment expansion. AD - Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, CT 06520, USA. sanjay.basu@yale.edu AN - 18816192 AU - Basu, S. AU - Orenstein, E. AU - Galvani, A. P. DA - Nov 15 DO - 10.1086/592508 [doi] DP - Nlm ET - 09/26 KW - AIDS-Related Opportunistic Infections/epidemiology/ immunology/microbiology Computer Simulation Disease Outbreaks Disease Progression HIV Infections/complications Models, Theoretical Mycobacterium tuberculosis/genetics/ immunology Risk Assessment Tuberculosis, Multidrug-Resistant/complications/epidemiology/ immunology/transmission L1 - internal-pdf://1066362079/Basu-2008-The theoretical influence of immunit.pdf LA - eng N1 - Basu, Sanjay Orenstein, Evan Galvani, Alison P Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Research Support, U.S. Gov't, P.H.S. United States The Journal of infectious diseases J Infect Dis. 2008 Nov 15;198(10):1502-13. PY - 2008 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 0022-1899 (Print) 0022-1899 (Linking) SP - 1502-13 ST - The theoretical influence of immunity between strain groups on the progression of drug-resistant tuberculosis epidemics T2 - J Infect Dis TI - The theoretical influence of immunity between strain groups on the progression of drug-resistant tuberculosis epidemics UR - http://jid.oxfordjournals.org/content/198/10/1502.full.pdf https://watermark.silverchair.com/198-10-1502.pdf?token=AQECAHi208BE49Ooan9kkhW_Ercy7Dm3ZL_9Cf3qfKAc485ysgAAAdIwggHOBgkqhkiG9w0BBwagggG_MIIBuwIBADCCAbQGCSqGSIb3DQEHATAeBglghkgBZQMEAS4wEQQMij7ru7s6F3k_DsN9AgEQgIIBhWKfi0LKfOvH-2OWfFngqPN8NWuvizyxg2nhupaw8nP0KovK--SfpeYKkD7CNSemAXaQIumULPPZeuIa0kBW0RhnpPDWWtqxTFXexYo3hP7Juh7wR2ZRFht5vcgqUgEaETCbzuus5fyAh27xBS7fYVtVzZ7DizsOi_5PSNyeIPD0JIMxIXrm1MMZyyGA-ze0Wy_xqG_Rdnmkbo5eYcxqCeTKfYwao1gKXn8ONPNNhioNAGmrMt60ILFNblA9EhF_yujGj22m1eCs1tJakxMkWbZBwAsZr-Sk-h4Hk4UWapsWHgFDWhidvxFoIJuGO3ujaMjQFLj_HfeExOZ6X8iN0FrQCRRszYtxvsQoQAU8zlCknVx6461AprjA4RSGqQ-1XpYtljiYdP6mzbIRVUoNeGivrBN_msJj1fTc5yvpaja0BOO_6ieDy3O8r8M_6i63bDisi5o3HDO8j7H2Hj_ReyUOvUFk8xfeqGM08MfCNv9o-4mzkZCJCg0NkmGq5fzNjN5arcGH VL - 198 ID - 2516 ER - TY - JOUR AB - Epidemic control strategies alter the spread of the disease in the host population. In this paper, we describe and discuss mathematical models that can be used to explore the potential of pre-exposure and post-exposure vaccines currently under development in the control of tuberculosis. A model with bacille Calmette-Guerin (BCG) vaccination for the susceptibles and treatment for the infectives is first presented. The epidemic thresholds known as the basic reproduction numbers and equilibria for the models are determined and stabilities are investigated. The reproduction numbers for the models are compared to assess the impact of the vaccines currently under development. The centre manifold theory is used to show the existence of backward bifurcation when the associated reproduction number is less than unity and that the unique endemic equilibrium is locally asymptotically stable when the associated reproduction number is greater than unity. From the study we conclude that the pre-exposure vaccine currently under development coupled with chemoprophylaxis for the latently infected and treatment of infectives is more effective when compared to the post-exposure vaccine currently under development for the latently infected coupled with treatment of the infectives. AD - Modelling Biomedical Systems Research Group, Department of Applied Mathematics, National University of Science and Technology, P.O. Box AC 939 Ascot, Bulawayo, Zimbabwe. cpbhunu1762@nust.ac.zw AN - 18644386 AU - Bhunu, C. P. AU - Garira, W. AU - Mukandavire, Z. AU - Magombedze, G. DA - Oct 7 DO - S0022-5193(08)00309-3 [pii] 10.1016/j.jtbi.2008.06.023 [doi] DP - Nlm ET - 07/23 KW - Antitubercular Agents/therapeutic use Basic Reproduction Number Carrier State/drug therapy Computational Biology Disease Outbreaks/prevention & control Humans Models, Biological Tuberculosis/ epidemiology/ prevention & control/therapy Tuberculosis Vaccines/therapeutic use LA - eng N1 - Bhunu, C P Garira, W Mukandavire, Z Magombedze, G Research Support, Non-U.S. Gov't Netherlands Journal of theoretical biology J Theor Biol. 2008 Oct 7;254(3):633-49. Epub 2008 Jul 1. PY - 2008 RN - fulltext fulltext_1208 SN - 1095-8541 (Electronic) 0022-5193 (Linking) SP - 633-49 ST - Modelling the effects of pre-exposure and post-exposure vaccines in tuberculosis control T2 - J Theor Biol TI - Modelling the effects of pre-exposure and post-exposure vaccines in tuberculosis control UR - http://ac.els-cdn.com/S0022519308003093/1-s2.0-S0022519308003093-main.pdf?_tid=9cd3afbb621724c7f1c7b776db347970&acdnat=1345011996_6faf58a30be5ee9615d3855da6ebe4a6 VL - 254 ID - 2517 ER - TY - JOUR AB - A tuberculosis model which incorporates treatment of infectives and chemoprophylaxis is presented. The model assumes that latently infected individuals develop active disease as a result of endogenous re-activation, exogenous re-infection and disease relapse, though a small fraction is assumed to develop active disease soon after infection. We start by formulating and analyzing a TB model without any intervention strategy that we extend to incorporate chemoprophylaxis and treatment of infectives. The epidemic thresholds known as reproduction numbers and equilibria for the models are determined, and stabilities analyzed. The reproduction numbers for the models are compared to assess the possible community benefits achieved by treatment of infectives, chemoprophylaxis and a holistic approach of these intervention strategies. The study shows that treatment of infectives is more effective in the first years of implementation (approximately 10 years) as treatment results in clearing active TB immediately and there after chemoprophylaxis will do better in controlling the number of infectives due to reduced progression to active TB. AD - Modelling Biomedical Systems Research Group, Department of Applied Mathematics, National University of Science and Technology, P.O. Box 939 Ascot, Bulawayo, Zimbabwe. cpbhunu1762@nust.ac.zw AN - 18231839 AU - Bhunu, C. P. AU - Garira, W. AU - Mukandavire, Z. AU - Zimba, M. DA - May DO - 10.1007/s11538-008-9295-4 [doi] DP - Nlm ET - 01/31 KW - Antitubercular Agents/therapeutic use Carrier State/drug therapy/prevention & control/transmission Humans Mathematics Models, Biological Recurrence Tuberculosis, Pulmonary/ drug therapy/prevention & control/ transmission LA - eng N1 - Bhunu, C P Garira, W Mukandavire, Z Zimba, M Research Support, Non-U.S. Gov't United States Bulletin of mathematical biology Bull Math Biol. 2008 May;70(4):1163-91. Epub 2008 Jan 30. PY - 2008 RN - fulltext fulltext_1208 SN - 0092-8240 (Print) 0092-8240 (Linking) SP - 1163-91 ST - Tuberculosis transmission model with chemoprophylaxis and treatment T2 - Bull Math Biol TI - Tuberculosis transmission model with chemoprophylaxis and treatment UR - http://www.springerlink.com/content/f553q1508h5073g8/ VL - 70 ID - 2518 ER - TY - JOUR AB - Mathematical models that describe the global spread of infectious diseases such as influenza, severe acute respiratory syndrome (SARS), and tuberculosis (TB) often consider a sample of international airports as a network supporting disease spread. However, there is no consensus on how many cities should be selected or on how to select those cities. Using airport flight data that commercial airlines reported to the Official Airline Guide (OAG) in 2000, we have examined the network characteristics of network samples obtained under different selection rules. In addition, we have examined different size samples based on largest flight volume and largest metropolitan populations. We have shown that although the bias in network characteristics increases with the reduction of the sample size, a relatively small number of areas that includes the largest airports, the largest cities, the most-connected cities, and the most central cities is enough to describe the dynamics of the global spread of influenza. The analysis suggests that a relatively small number of cities (around 200 or 300 out of almost 3000) can capture enough network information to adequately describe the global spread of a disease such as influenza. Weak traffic flows between small airports can contribute to noise and mask other means of spread such as the ground transportation. AD - RTI International, Research Triangle Park, North Carolina, United States of America. bobashev@rti.org AN - 18776932 AU - Bobashev, G. AU - Morris, R. J. AU - Goedecke, D. M. DO - 10.1371/journal.pone.0003154 [doi] DP - Nlm ET - 09/09 KW - Aircraft Aviation Communicable Diseases/ epidemiology/transmission Disease Outbreaks Geography Humans Influenza, Human/epidemiology/transmission Models, Theoretical Severe Acute Respiratory Syndrome/transmission Travel Tuberculosis/epidemiology/transmission LA - eng N1 - Bobashev, Georgiy Morris, Robert J Goedecke, D Michael U01GM070698/GM/NIGMS NIH HHS/United States Research Support, N.I.H., Extramural United States PloS one PLoS One. 2008 Sep 8;3(9):e3154. PY - 2008 RN - fulltext fulltext_1208 SN - 1932-6203 (Electronic) 1932-6203 (Linking) SP - e3154 ST - Sampling for global epidemic models and the topology of an international airport network T2 - PLoS One TI - Sampling for global epidemic models and the topology of an international airport network UR - http://www.plosone.org/article/fetchObjectAttachment.action?uri=info%3Adoi%2F10.1371%2Fjournal.pone.0003154&representation=PDF VL - 3 ID - 2519 ER - TY - JOUR AU - Cohen, T. AU - Colijn, C. AU - Finklea, B. AU - Wright, A. AU - Zignol, M. AU - Pym, A. AU - Murray, M. L1 - internal-pdf://2445009922/Cohen-2008-Are Survey-Based Estimates of the B.pdf PY - 2008 RN - fulltext fulltext_1208 SP - e2363 ST - Are Survey-Based Estimates of the Burden of Drug Resistant TB Too Low? Insight from a Simulation Study T2 - PLoS One TI - Are Survey-Based Estimates of the Burden of Drug Resistant TB Too Low? Insight from a Simulation Study UR - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2408555/pdf/pone.0002363.pdf https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2408555/pdf/pone.0002363.pdf VL - 3 ID - 2520 ER - TY - JOUR AB - While bacillus Calmette-Guerin vaccination plays an important role in reducing the morbidity of tuberculosis (TB) infection during childhood, new tuberculosis vaccines are necessary to disrupt the transmission of disease and improve global control of this pathogen. Growing evidence of the presence of meaningful Mycobacterium tuberculosis strain diversity, coupled with the possibility that new vaccines may differentially protect against infection or disease with circulating M. tuberculosis strains, suggest that these vaccines may have complicated effects on disease dynamics. We use a mathematical model to explore the potential effects of strain diversity on the performance of vaccines and find that vaccines offer great promise for improving tuberculosis control, but the expected benefits of mass vaccination will be eroded if strain replacement with M. tuberculosis variants that are not effectively targeted by vaccines occurs. Determining the likelihood of strain replacement will require additional knowledge of the strain specificities of current vaccine candidates, and an improved understanding of the mechanisms of strain interaction, which are responsible for maintaining the diversity of M. tuberculosis within communities. AD - Division of Global Health Equity, Brigham and Women's Hospital, Boston MA 02115, USA. tcohen@hsph.harvard.edu AN - 18849476 AU - Cohen, T. AU - Colijn, C. AU - Murray, M. DA - Oct 21 DO - 0808746105 [pii] 10.1073/pnas.0808746105 [doi] DP - Nlm ET - 10/14 KW - Models, Biological Tuberculosis/immunology Tuberculosis Vaccines/ classification/ immunology LA - eng N1 - Cohen, Ted Colijn, Caroline Murray, Megan K08 AI055985-06/AI/NIAID NIH HHS/United States Research Support, N.I.H., Extramural United States Proceedings of the National Academy of Sciences of the United States of America Proc Natl Acad Sci U S A. 2008 Oct 21;105(42):16302-7. Epub 2008 Oct 10. PY - 2008 RN - fulltext fulltext_1208 SN - 1091-6490 (Electronic) 0027-8424 (Linking) SP - 16302-7 ST - Modeling the effects of strain diversity and mechanisms of strain competition on the potential performance of new tuberculosis vaccines T2 - Proc Natl Acad Sci U S A TI - Modeling the effects of strain diversity and mechanisms of strain competition on the potential performance of new tuberculosis vaccines UR - http://www.pnas.org/content/105/42/16302.full.pdf VL - 105 ID - 2521 ER - TY - JOUR AB - Technologies for strain differentiation and typing have made it possible to detect genetic diversity of pathogens, both within individual hosts and within communities. Coinfection of a host by more than one pathogen strain may affect the relative frequency of these strains at the population level through complex within- and between-host interactions; in infectious diseases that have a long latent period, interstrain competition during latency is likely to play an important role in disease dynamics. We show that SEIR models that include a class of latently coinfected individuals can have markedly different long-term dynamics than models without coinfection, and that coinfection can greatly facilitate the stable coexistence of strains. We demonstrate these dynamics using a model relevant to tuberculosis in which people may experience latent coinfection with both drug sensitive and drug resistant strains. Using this model, we show that the existence of a latent coinfected state allows the possibility that disease control interventions that target latency may facilitate the emergence of drug resistance. AD - Department of Engineering Mathematics, University of Bristol, Bristol, UK. ccolijn@gmail.com AN - 19082663 AU - Colijn, C. AU - Cohen, T. AU - Murray, M. DA - Jan DO - 10.1007/s11538-008-9361-y [doi] DP - Nlm ET - 12/17 KW - Basic Reproduction Number Biodiversity Communicable Diseases/drug therapy/ microbiology Drug Resistance, Bacterial/genetics Host-Pathogen Interactions/drug effects/immunology Humans Incidence Infectious Disease Incubation Period Models, Biological Mycobacterium/drug effects/genetics/immunology Nonlinear Dynamics Selection, Genetic Species Specificity Tuberculosis/drug therapy/immunology/microbiology Virus Latency/physiology L1 - internal-pdf://1123055917/Colijn-2008-Latent coinfection and the mainten.pdf LA - eng N1 - Colijn, Caroline Cohen, Ted Murray, Megan K08 AI055985-06/AI/NIAID NIH HHS/United States United States Bulletin of mathematical biology Nihms94718 Bull Math Biol. 2009 Jan;71(1):247-63. Epub 2008 Dec 10. PY - 2008 RN - fulltext fulltext_1208 SN - 1522-9602 (Electronic) 0092-8240 (Linking) SP - 247-63 ST - Latent coinfection and the maintenance of strain diversity T2 - Bull Math Biol TI - Latent coinfection and the maintenance of strain diversity UR - http://www.springerlink.com/content/y426974338578126/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2652765/pdf/nihms-94718.pdf VL - 71 ID - 2562 ER - TY - JOUR AB - BACKGROUND: Numerous studies of interferon-gamma release assays (IGRAs) and tuberculin skin testing (TST) to assess latent tuberculosis infection have been published without a framework to understand the extent to which these two tests should agree. Analyzing the causes of variability in agreement levels is crucial. METHODS: A mathematical model of agreement between dichotomous tests was used to understand variations in the level of agreement between IGRA and TST results. The effect of cut-off point selection on agreement was also explored using the model. Model-based predictions are illustrated using published literature. RESULTS: Analyses of IGRAs and TST that depart from model predictions are an indication that surrogates of prevalence of Mycobacterium tuberculosis infection may have been improperly measured or analyzed. For fixed prevalence, the extent of agreement between tests depends upon cut-off point selection. Changing cut-off points while holding prevalence constant may lead to increasing, decreasing or even no change in agreement. CONCLUSIONS: Researchers have recognized that experimental error, clinical risk and prevalence of non-tuberculous mycobacteria contribute to study-to-study variability. In the present study, we show that paradoxical findings in certain IGRA studies can be explained by the proposed mathematical model. Re-analysis of existing studies may lead to overlooked hypotheses. Future IGRA studies will require epidemiologically well-characterized populations. AD - Global Tuberculosis Institute, New Jersey Medical School, Newark, New Jersey, USA. davidoal@umdnj.edu AN - 18230247 AU - Davidow, A. L. AU - Affouf, M. DA - Feb DP - Nlm ET - 01/31 KW - Humans Interferon-gamma/ secretion Research Design Sensitivity and Specificity Tuberculin Test Tuberculosis/ diagnosis LA - eng N1 - Davidow, A L Affouf, M France The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease Int J Tuberc Lung Dis. 2008 Feb;12(2):152-9. PY - 2008 RN - fulltext fulltext_1208 SN - 1027-3719 (Print) 1027-3719 (Linking) SP - 152-9 ST - Making sense of agreement among interferon-gamma release assays and tuberculosis skin testing T2 - Int J Tuberc Lung Dis TI - Making sense of agreement among interferon-gamma release assays and tuberculosis skin testing VL - 12 ID - 2522 ER - TY - JOUR AB - South Africa has high rates of tuberculosis (TB), including multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains. Expanding access to culture and drug susceptibility testing (DST) for TB diagnosis may help control this epidemic, but the potential impact of existing and novel TB diagnostics is uncertain. By fitting to World Health Organization epidemiological estimates, we developed a compartmental difference-equation model of the TB/HIV epidemic among South African adults. Performing culture and DST in 37% of new cases and 85% of previously treated cases was projected to save 47,955 lives (17.2% reduction in TB mortality, 95% simulation interval (S.I.) 8.9-24.4%), avert 7,721 MDR-TB cases (14.1% reduction, 95% S.I. 5.3-23.8%), and prevent 46.6% of MDR-TB deaths (95% S.I. 32.6-56.0%) in South Africa over 10 years. Used alone, expanded culture and DST did not reduce XDR-TB incidence, but they enhanced the impact of transmission-reduction strategies, such as respiratory isolation. In South Africa, expanding TB culture and DST could substantially reduce TB, and particularly MDR-TB, mortality. Control of XDR-TB will require additional interventions, the impact of which may be enhanced by improved TB diagnosis. AD - Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Suite W6508, Baltimore, MD 21205, USA. AN - 18695217 AU - Dowdy, D. W. AU - Chaisson, R. E. AU - Maartens, G. AU - Corbett, E. L. AU - Dorman, S. E. DA - Aug 12 DO - 0800965105 [pii] 10.1073/pnas.0800965105 [doi] DP - Nlm ET - 08/13 KW - Disease Outbreaks Drug Resistance, Multiple, Bacterial Female HIV Infections/complications/ diagnosis/ mortality/transmission Humans Male Models, Theoretical Retrospective Studies South Africa/epidemiology Time Factors Tuberculosis/complications/ diagnosis/ mortality/transmission World Health Organization L1 - internal-pdf://3950028845/Dowdy-2008-Impact of enhanced tuberculosis dia.pdf LA - eng N1 - Dowdy, David W Chaisson, Richard E Maartens, Gary Corbett, Elizabeth L Dorman, Susan E 074644/Wellcome Trust/United Kingdom K23 AI51528/AI/NIAID NIH HHS/United States K24 AI01637/AI/NIAID NIH HHS/United States T32 GMO7309/PHS HHS/United States Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't United States Proceedings of the National Academy of Sciences of the United States of America Proc Natl Acad Sci U S A. 2008 Aug 12;105(32):11293-8. Epub 2008 Aug 11. PY - 2008 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1091-6490 (Electronic) 0027-8424 (Linking) SP - 11293-8 ST - Impact of enhanced tuberculosis diagnosis in South Africa: a mathematical model of expanded culture and drug susceptibility testing T2 - Proc Natl Acad Sci U S A TI - Impact of enhanced tuberculosis diagnosis in South Africa: a mathematical model of expanded culture and drug susceptibility testing UR - http://www.pnas.org/content/105/32/11293.full.pdf https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2516234/pdf/zpq11293.pdf VL - 105 ID - 2523 ER - TY - JOUR AB - SETTING: The potential cost-effectiveness of improved diagnostic tests for tuberculosis (TB) in resource-limited settings is unknown. OBJECTIVE: To estimate the incremental cost-effectiveness of a hypothetical new point-of-care TB diagnostic test in South Africa, Brazil and Kenya. DESIGN: Decision-analysis model, adding four diagnostic interventions (sputum smear microscopy, new test, smear plus new test and smear plus TB culture) to a baseline of existing infrastructure without smear. RESULTS: Adding sputum smear was estimated to be more cost-effective (incremental cost per disability-adjusted life year [DALY] of $86 [South Africa], $131 [Brazil], $38 (Kenya]) than a new TB diagnostic with 70% sensitivity, 95% specificity and price of $20 per test ($198 [South Africa], $275 [Brazil], $84 [Kenya]). However, compared to sputum smear, smear plus new test averted 46-49% more DALYs per 1000 TB suspects (321 vs. 215 [South Africa], 243 vs. 166 [Brazil], 790 vs. 531 [Kenya]), at an incremental cost of $170 (Kenya) to $625 (Brazil) per DALY averted. Cost-effectiveness was most sensitive to the specificity and price of the new test, the baseline TB case detection rate and the discount rate. CONCLUSION: Novel diagnostic tests for TB are potentially highly cost-effective. Cost-effectiveness is maximized by high-specificity, low-cost tests deployed to regions with poor infrastructure. AD - Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA. david.w.dowdy@gmail.com AN - 18713499 AU - Dowdy, D. W. AU - O'Brien, M. A. AU - Bishai, D. DA - Sep ET - 08/21 J2 - The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease KW - Brazil Cost-Benefit Analysis Decision Support Techniques Diagnostic Tests, Routine/*economics/methods Humans Kenya Models, Economic Sensitivity and Specificity South Africa Tuberculosis/*diagnosis/drug therapy/economics LA - eng M3 - Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't N1 - Dowdy, D W O'Brien, M A Bishai, D 5 T32 GM07309/GM/NIGMS NIH HHS/ France Int J Tuberc Lung Dis. 2008 Sep;12(9):1021-9. PY - 2008 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1027-3719 (Print) 1027-3719 (Linking) SP - 1021-9 ST - Cost-effectiveness of novel diagnostic tools for the diagnosis of tuberculosis T2 - Int J Tuberc Lung Dis TI - Cost-effectiveness of novel diagnostic tools for the diagnosis of tuberculosis UR - http://www.ncbi.nlm.nih.gov/pubmed/18713499 VL - 12 ID - 2525 ER - TY - JOUR AB - Using fuzzy set theory, we created a system, that assesses a herb's usefulness for the treatment of tuberculosis, based on ethnobotanical data. We analysed two systems which contain different amount of inputs. The first system contains four inputs, the second one contains six inputs. We used the Takagi-Sugeno-Kanga model. Mamdani model is poor at representation as it needs more fuzzy rules than that of TSK to model a real world system where accuracy is demanded. It has been employed a fuzzy controller, and a fuzzy model, in successfully solving difficult control and modelling problems in practice. It is implemented in the Fuzzy Logic Toolbox in Matlab. The data for inputs are gathered in the database named SOPAT (selection of plants against tuberculosis), which is part of a project coordinated by the Oxford International Biomedical Centre. In this database there could be up to one million plant species. It would be cumbersome to select a remedy from one (or some) of these species looking at the data base one-by-one. By means of the fuzzy set theory this remedy can be chosen very quickly. AD - Section of Physics and Applied Mathematics, Faculty of Chemistry, Silesian University of Technology, Ks M Strzody 9, Gliwice, Poland. gmdudek@polsl.pl AN - 18773936 AU - Dudek, G. AU - Grzywna, Z. J. AU - Willcox, M. L. DA - Dec DO - S0303-2647(08)00178-0 [pii] 10.1016/j.biosystems.2008.05.038 [doi] DP - Nlm ET - 09/09 KW - Algorithms Antitubercular Agents/ classification Databases, Factual Ethnobotany Fuzzy Logic Models, Biological Plants, Medicinal/ classification LA - eng N1 - Dudek, Gabriela Grzywna, Zbigniew J Willcox, Merlin L Comparative Study Research Support, Non-U.S. Gov't Ireland Bio Systems Biosystems. 2008 Dec;94(3):285-9. Epub 2008 Aug 19. PY - 2008 RN - fulltext fulltext_1208 SN - 1872-8324 (Electronic) 0303-2647 (Linking) SP - 285-9 ST - Classification of antituberculosis herbs for remedial purposes by using fuzzy sets T2 - Biosystems TI - Classification of antituberculosis herbs for remedial purposes by using fuzzy sets UR - http://ac.els-cdn.com/S0303264708001780/1-s2.0-S0303264708001780-main.pdf?_tid=60b5fc21b1e4026d50b5c1d377ffa514&acdnat=1345012294_d85e1d01b0a71e7a5bd6ff4083250257 VL - 94 ID - 2526 ER - TY - JOUR AB - BACKGROUND: The current understanding of airborne tuberculosis (TB) transmission is based on classic 1950s studies in which guinea pigs were exposed to air from a tuberculosis ward. Recently we recreated this model in Lima, Peru, and in this paper we report the use of molecular fingerprinting to investigate patient infectiousness in the current era of HIV infection and multidrug-resistant (MDR) TB. METHODS AND FINDINGS: All air from a mechanically ventilated negative-pressure HIV-TB ward was exhausted over guinea pigs housed in an airborne transmission study facility on the roof. Animals had monthly tuberculin skin tests, and positive reactors were removed for autopsy and organ culture for M. tuberculosis. Temporal exposure patterns, drug susceptibility testing, and DNA fingerprinting of patient and animal TB strains defined infectious TB patients. Relative patient infectiousness was calculated using the Wells-Riley model of airborne infection. Over 505 study days there were 118 ward admissions of 97 HIV-positive pulmonary TB patients. Of 292 exposed guinea pigs, 144 had evidence of TB disease; a further 30 were tuberculin skin test positive only. There was marked variability in patient infectiousness; only 8.5% of 118 ward admissions by TB patients were shown by DNA fingerprinting to have caused 98% of the 125 characterised cases of secondary animal TB. 90% of TB transmission occurred from inadequately treated MDR TB patients. Three highly infectious MDR TB patients produced 226, 52, and 40 airborne infectious units (quanta) per hour. CONCLUSIONS: A small number of inadequately treated MDR TB patients coinfected with HIV were responsible for almost all TB transmission, and some patients were highly infectious. This result highlights the importance of rapid TB drug-susceptibility testing to allow prompt initiation of effective treatment, and environmental control measures to reduce ongoing TB transmission in crowded health care settings. TB infection control must be prioritized in order to prevent health care facilities from disseminating the drug-resistant TB that they are attempting to treat. AD - Department of Infectious Diseases and Immunity, Imperial College London, United Kingdom. rod.escombe@imperial.ac.uk AN - 18798687 AU - Escombe, A. R. AU - Moore, D. A. AU - Gilman, R. H. AU - Pan, W. AU - Navincopa, M. AU - Ticona, E. AU - Martinez, C. AU - Caviedes, L. AU - Sheen, P. AU - Gonzalez, A. AU - Noakes, C. J. AU - Friedland, J. S. AU - Evans, C. A. DA - Sep 30 J2 - PLoS medicine L1 - internal-pdf://3320319453/Escombe-2008-The infectiousness of tuberculosi.pdf LA - eng N1 - T35A107646/PHS HHS/United States Wellcome Trust/United Kingdom Journal Article Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. United States PY - 2008 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1549-1676 (Electronic) SP - e188 ST - The infectiousness of tuberculosis patients coinfected with HIV T2 - PLoS Med TI - The infectiousness of tuberculosis patients coinfected with HIV UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=18798687http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2535657/pdf/pmed.0050188.pdf https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2535657/pdf/pmed.0050188.pdf VL - 5 ID - 2528 ER - TY - JOUR AB - Minisatellites are highly variable tandem repeats used for over 20 years in humans for DNA fingerprinting. In prokaryotes fingerprinting techniques exploiting VNTR (variable number of tandem repeats) polymorphisms have become widely used recently in bacterial typing. However although many investigations into the mechanisms underlying minisatellite variation in humans have been performed, relatively little is known about the processes that mediate bacterial minisatellite polymorphism. An understanding of this is important since it will influence how the results from VNTR experiments are interpreted. The minisatellites of Mycobacterium tuberculosis are well characterized since they are some of the few polymorphic loci in what is otherwise a very homogeneous organism. Using VNTR results from a well-defined and characterized set of M. tuberculosis strains we show that the repeats at a locus are likely to evolve by stepwise contraction or expansion in the number of repeats. A stochastic continuous-time population mathematical model was developed to simulate the evolution of the repeats. This allowed estimation of the tendency of the repeats to increase or decrease and the rate at which they change. The majority of loci tend to lose rather than gain repeats. All of the loci mutate extremely slowly, with an average rate of 2.3 x 10(-8), which is 350 times slower than that of a set of VNTR repeats with similar diversity observed experimentally in Escherichia coli. This suggests that the VNTR profile of a strain of M. tuberculosis will be indicative of its clonal lineage and will be unlikely to vary in epidemiologically-related strains. AD - Statistics Unit, Statistics, Modelling and Bioinformatics Department, Centre for Infections, Health Protection Agency, 61 Colindale Avenue, London NW9 5EQ, UK. AN - 18458805 AU - Grant, A. AU - Arnold, C. AU - Thorne, N. AU - Gharbia, S. AU - Underwood, A. DA - Jun DO - 10.1007/s00239-008-9104-6 [doi] DP - Nlm ET - 05/07 KW - Evolution, Molecular Minisatellite Repeats Models, Genetic Mutation Mycobacterium tuberculosis/classification/ genetics LA - eng N1 - Grant, Andrew Arnold, Catherine Thorne, Nicola Gharbia, Saheer Underwood, Anthony Research Support, Non-U.S. Gov't Germany Journal of molecular evolution J Mol Evol. 2008 Jun;66(6):565-74. Epub 2008 May 6. PY - 2008 RN - fulltext fulltext_1208 SN - 0022-2844 (Print) 0022-2844 (Linking) SP - 565-74 ST - Mathematical modelling of Mycobacterium tuberculosis VNTR loci estimates a very slow mutation rate for the repeats T2 - J Mol Evol TI - Mathematical modelling of Mycobacterium tuberculosis VNTR loci estimates a very slow mutation rate for the repeats UR - http://www.springerlink.com/content/j2j4v867632868gu/ VL - 66 ID - 2529 ER - TY - JOUR AB - Knowing how to control a pathogen that infects more than one host species is of increasing importance because the incidence of such infections grows with continuing environmental change. Of concern are infections transmitted from wildlife to humans or livestock. To determine which options are available to control a pathogen in these circumstances, we analyze the pathogen invasion matrix for the multihost susceptible-infected-susceptible model. We highlight the importance of both community structure and the column sum or row sum index, an indicator of both force of infection and community stability. We derive a set of guidelines for constructing culling strategies and suggest a hybrid strategy that has the advantages of both the bottom-up and the top-down approaches, which we study in some detail. The analysis holds for an arbitrary number of host species, enabling the analysis of large-scale ecological systems and systems with spatial dimensions. We test the robustness of our methods by making two changes in the structure of the underlying dynamic model, adding direct competition and introducing frequency-dependent infection transmission. In particular, we show that the introduction of an additional host can eliminate the pathogen rather than eliminate the resident host. The discussion is illustrated with a reference to bovine tuberculosis. AD - Department of Computing Science and Mathematics, University of Stirling, Stirling FK9 4LA, Scotland, United Kingdom. j.v.greenman@stir.ac.uk AN - 18771403 AU - Greenman, J. V. AU - Hoyle, A. S. DA - Oct DO - 10.1086/590967 DP - NLM ET - 2008/09/06 IS - 4 J2 - The American naturalist KW - Animals Cattle Disease Reservoirs *Host-Pathogen Interactions Humans Models, Biological Mustelidae Tuberculosis, Bovine/immunology/*microbiology LA - eng N1 - 1537-5323 Greenman, J V Hoyle, A S Journal Article United States Am Nat. 2008 Oct;172(4):576-84. doi: 10.1086/590967. PY - 2008 SN - 0003-0147 SP - 576-84 ST - Exclusion of generalist pathogens in multihost communities T2 - Am Nat TI - Exclusion of generalist pathogens in multihost communities VL - 172 ID - 2945 ER - TY - JOUR AB - We conducted a decision analysis to assess and compare four algorithms for amplified Mycobacterium tuberculosis direct (MTD) testing of respiratory specimens in terms of cost-effectiveness. The most cost-effective strategy was one in which smear-positive specimens but not smear-negative specimens were diluted prior to MTD testing. AD - Johns Hopkins University Center for Tuberculosis Research, 1550 Orleans Street, Room 1M-06, Baltimore, MD 21231, USA. AN - 18799694 AU - Guerra, R. L. AU - Hooper, N. M. AU - Baker, J. F. AU - Alborz, R. AU - Armstrong, D. T. AU - Kiehlbauch, J. A. AU - Conde, M. B. AU - Dorman, S. E. DA - Nov DO - JCM.01682-08 [pii] 10.1128/JCM.01682-08 ET - 09/19 KW - Cost-Benefit Analysis Humans Mycobacterium tuberculosis/genetics/*isolation & purification Nucleic Acid Amplification Techniques/*economics/*methods Tuberculosis, Pulmonary/*diagnosis/microbiology LA - eng N1 - Guerra, Renata L Hooper, Nancy M Baker, James F Alborz, Roya Armstrong, Derek T Kiehlbauch, Julia A Conde, Marcus B Dorman, Susan E D43 TW05574-01/TW/FIC NIH HHS/United States K23AI51528/AI/NIAID NIH HHS/United States U19AI45432/AI/NIAID NIH HHS/United States U2R TW006883/TW/FIC NIH HHS/United States Research Support, N.I.H., Extramural United States Journal of clinical microbiology J Clin Microbiol. 2008 Nov;46(11):3811-2. Epub 2008 Sep 17. PY - 2008 RN - fulltext fulltext_1208 SN - 1098-660X (Electronic) 0095-1137 (Linking) SP - 3811-2 ST - Cost-effectiveness of different strategies for amplified Mycobacterium tuberculosis direct testing for cases of pulmonary tuberculosis T2 - J Clin Microbiol TI - Cost-effectiveness of different strategies for amplified Mycobacterium tuberculosis direct testing for cases of pulmonary tuberculosis UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=18799694http://jcm.asm.org/cgi/reprint/46/11/3811.pdfhttp://www.ncbi.nlm.nih.gov/pmc/articles/PMC2576624/pdf/1682-08.pdf VL - 46 ID - 2530 ER - TY - JOUR AB - The resurgence of multi-drug-resistant tuberculosis in some parts of Europe and North America calls for a mathematical study to assess the impact of the emergence and spread of such strain on the global effort to effectively control the burden of tuberculosis. This paper presents a deterministic compartmental model for the transmission dynamics of two strains of tuberculosis, a drug-sensitive (wild) one and a multi-drug-resistant strain. The model allows for the assessment of the treatment of people infected with the wild strain. The qualitative analysis of the model reveals the following. The model has a disease-free equilibrium, which is locally asymptotically stable if a certain threshold, known as the effective reproduction number, is less than unity. Further, the model undergoes a backward bifurcation, where the disease-free equilibrium coexists with a stable endemic equilibrium. One of the main novelties of this study is the numerical illustration of tri-stable equilibria, where the disease-free equilibrium coexists with two stable endemic equilibrium when the aforementioned threshold is less than unity, and a bi-stable setup, involving two stable endemic equilibria, when the effective reproduction number is greater than one. This, to our knowledge, is the first time such dynamical features have been observed in TB dynamics. Finally, it is shown that the backward bifurcation phenomenon in this model arises due to the exogenous re-infection property of tuberculosis. AD - Department of Mathematics, University of Manitoba, Winnipeg, Manitoba, Canada. gumelab@cc.umanitoba.ca AN - 18616351 AU - Gumel, A. B. AU - Song, B. DA - Jul DP - Nlm ET - 07/12 KW - Algorithms Antitubercular Agents/therapeutic use Disease Outbreaks Drug Resistance, Bacterial Humans Mathematics Models, Statistical Models, Theoretical Mycobacterium tuberculosis/ metabolism Pharmaceutical Preparations Tuberculosis/microbiology/ transmission Tuberculosis, Multidrug-Resistant/ epidemiology/transmission LA - eng N1 - Gumel, Abba B Song, Baojun United States Mathematical biosciences and engineering : MBE Math Biosci Eng. 2008 Jul;5(3):437-55. PY - 2008 RN - fulltext fulltext_1208 SN - 1547-1063 (Print) 1547-1063 (Linking) SP - 437-55 ST - Existence of multiple-stable equilibria for a multi-drug-resistant model of Mycobacterium tuberculosis T2 - Math Biosci Eng TI - Existence of multiple-stable equilibria for a multi-drug-resistant model of Mycobacterium tuberculosis VL - 5 ID - 2531 ER - TY - JOUR AB - This paper presents two new theoretical frameworks to investigate the impact of immigration on the transmission dynamics of tuberculosis. For the basic model, we present new analysis on the existence and stability of equilibria. Then, we use numerical simulations of the model to illustrate the behavior of the system. We apply the model to Canadian reported data on tuberculosis and observe a good agreement between the model prediction and the data. For the extended model, which incorporated the recruitment of the latent and infectious in immigrants to the basic model, we find that the usual threshold condition does not apply and a unique equilibrium exists for all parameter values. This indicates that the disease does not disappear and becomes endemic in host areas. This finding is also supported by numerical simulations with the extended model. Our study suggests that immigrants have a considerable influence on the overall transmission dynamics behavior of tuberculosis. AD - School of Information Engineering, Beijing University of Posts and Telecommunications, 10 Xitucheng Road, Beijing 100876, PR China. AN - 18255113 AU - Jia, Z. W. AU - Tang, G. Y. AU - Jin, Z. AU - Dye, C. AU - Vlas, S. J. AU - Li, X. W. AU - Feng, D. AU - Fang, L. Q. AU - Zhao, W. J. AU - Cao, W. C. DA - May DO - S0040-5809(07)00136-0 [pii] 10.1016/j.tpb.2007.12.007 [doi] DP - Nlm ET - 02/08 KW - Emigration and Immigration Humans Models, Theoretical Tuberculosis/ epidemiology LA - eng N1 - Jia, Zhong-Wei Tang, Gong-You Jin, Zhen Dye, Christopher Vlas, Sake J Li, Xiao-Wen Feng, Dan Fang, Li-Qun Zhao, Wen-Juan Cao, Wu-Chun Research Support, Non-U.S. Gov't United States Theoretical population biology Theor Popul Biol. 2008 May;73(3):437-48. Epub 2007 Dec 27. PY - 2008 RN - fulltext fulltext_1208 SN - 1096-0325 (Electronic) 0040-5809 (Linking) SP - 437-48 ST - Modeling the impact of immigration on the epidemiology of tuberculosis T2 - Theor Popul Biol TI - Modeling the impact of immigration on the epidemiology of tuberculosis UR - http://ac.els-cdn.com/S0040580907001360/1-s2.0-S0040580907001360-main.pdf?_tid=6f3c9e5c3d75a3967a221ea8398403ca&acdnat=1345012518_7316eb0e4e39d2e662facb8eb34c462b VL - 73 ID - 2532 ER - TY - JOUR AB - BACKGROUND: Nearly the entire population of Japan has been vaccinated with Bacillus Calmette-Guerin (BCG), which causes a false-positive result in the tuberculin skin test (TST). The interferon-gamma release assay QuantiFERON-TB Gold (QFT) is a new alternative to the TST that can be used to screen for latent tuberculosis infection and active tuberculosis, as it has no cross-reactivity with BCG. METHODS: We constructed a Markov model to evaluate the cost effectiveness of the QFT for tuberculosis contact screening. The target population is a hypothetical cohort of 1000 immunocompetent 20-year-old individuals who have had contact with sputum-smear-positive pulmonary tuberculosis patients. The analysis was conducted from a societal perspective over the lifetime of a contact. We compared the QFT-alone strategy with the TST followed by QFT (TST/QFT) strategy and the TST-alone strategy. RESULTS: In a base-case analysis, the QFT-alone strategy was dominant ($US 471.54; 28.1099 quality-adjusted life-years [QALYs]), compared with the TST/QFT strategy ($US 500.55; 28.1087 QALYs) and the TST-alone strategy ($US573.98; 28.1079 QALYs). The incremental cost-effectiveness ratio of the QFT-alone strategy was a cost saving of $US23 043.5/QALY gained compared with the TST/QFT strategy. On one-way sensitivity analysis, TST specificity and the prevalence of tuberculosis/latent tuberculosis infection affected the cost effectiveness. The probabilistic analysis showed that the QFT-alone strategy has a 95% chance of being cost effective at a threshold ratio of $US2.10/QALY gained, compared with the TST/QFT strategy. CONCLUSION: The QFT-alone strategy is the most cost effective for tuberculosis contact screening in Japan. AD - Katsushika City Public Health Center, Tokyo, Japan. a-kowada@city.katsushika.lg.jp AN - 18652520 AU - Kowada, A. AU - Takahashi, O. AU - Shimbo, T. AU - Ohde, S. AU - Tokuda, Y. AU - Fukui, T. DP - Nlm ET - 07/26 J2 - Molecular diagnosis & therapy KW - Adult Aged Antitubercular Agents/therapeutic use BCG Vaccine/diagnostic use/ economics Carrier State/diagnosis Contact Tracing Cost-Benefit Analysis False Positive Reactions Humans Interferon-gamma/ blood Markov Chains Mass Screening/ economics/methods Middle Aged Models, Theoretical Sensitivity and Specificity Tuberculin Test/ economics/methods Tuberculosis/ diagnosis/drug therapy LA - eng N1 - Kowada, Akiko Takahashi, Osamu Shimbo, Takuro Ohde, Sachiko Tokuda, Yasuharu Fukui, Tsuguya New Zealand Mol Diagn Ther. 2008;12(4):235-51. PY - 2008 RN - fulltext fulltext_1208 SN - 1177-1062 (Print) 1177-1062 (Linking) SP - 235-51 ST - Cost effectiveness of interferon-gamma release assay for tuberculosis contact screening in Japan T2 - Mol Diagn Ther TI - Cost effectiveness of interferon-gamma release assay for tuberculosis contact screening in Japan VL - 12 ID - 2533 ER - TY - JOUR AB - BACKGROUND: Tuberculosis (TB) in prisons is a major health problem in countries of high and intermediate TB endemicity such as Brazil. For operational reasons, TB control strategies in prisons cannot be compared through population based intervention studies. METHODOLOGY/PRINCIPAL FINDINGS: A mathematical model is proposed to simulate the TB dynamics in prison and evaluate the potential impact on active TB prevalence of several intervention strategies. The TB dynamics with the ongoing program was simulated over a 10 year period in a Rio de Janeiro prison (TB prevalence 4.6 %). Then, a simulation of the DOTS strategy reaching the objective of 70 % of bacteriologically-positive cases detected and 85 % of detected cases cured was performed; this strategy reduced only to 2.8% the average predicted TB prevalence after 5 years. Adding TB detection at entry point to DOTS strategy had no major effect on the predicted active TB prevalence. But, adding further a yearly X-ray mass screening of inmates reduced the predicted active TB prevalence below 1%. Furthermore, according to this model, after applying this strategy during 2 years (three annual screenings), the TB burden would be reduced and the active TB prevalence could be kept at a low level by associating X-ray screening at entry point and DOTS. CONCLUSIONS/SIGNIFICANCE: We have shown that X-ray mass screenings should be considered to control TB in highly endemic prison. Prisons with different levels of TB prevalence could be examined thanks to this model which provides a rational tool for public health deciders. AD - U 707, INSERM, Paris, France. j.legrand@imperial.ac.uk AN - 18461123 AU - Legrand, J. AU - Sanchez, A. AU - Le Pont, F. AU - Camacho, L. AU - Larouze, B. DO - 10.1371/journal.pone.0002100 [doi] DP - Nlm ET - 05/08 KW - Brazil/epidemiology Crowding/ physiopathology Humans Mass Screening Models, Statistical Prisoners/ statistics & numerical data Prisons/standards/ statistics & numerical data Radiography, Thoracic Tuberculosis/epidemiology/ prevention & control/radiography/transmission LA - eng N1 - Legrand, Judith Sanchez, Alexandra Le Pont, Francoise Camacho, Luiz Larouze, Bernard Research Support, Non-U.S. Gov't United States PloS one PLoS One. 2008 May 7;3(5):e2100. PY - 2008 RN - fulltext fulltext_1208 SN - 1932-6203 (Electronic) 1932-6203 (Linking) SP - e2100 ST - Modeling the impact of tuberculosis control strategies in highly endemic overcrowded prisons T2 - PLoS One TI - Modeling the impact of tuberculosis control strategies in highly endemic overcrowded prisons UR - http://www.plosone.org/article/fetchObjectAttachment.action?uri=info%3Adoi%2F10.1371%2Fjournal.pone.0002100&representation=PDF VL - 3 ID - 2534 ER - TY - JOUR AB - BACKGROUND: Chronic obstructive pulmonary disease (COPD), lung cancer, and tuberculosis are three leading causes of death in China, where prevalences of smoking and solid-fuel use are also high. We aimed to predict the effects of risk-factor trends on COPD, lung cancer, and tuberculosis. METHODS: We used representative data sources to estimate past trends in smoking and household solid-fuel use and to construct a range of future scenarios. We obtained the aetiological effects of risk factors on diseases from meta-analyses of epidemiological studies and from large studies in China. We modelled future COPD and lung cancer mortality and tuberculosis incidence, taking into account the accumulation of hazardous effects of risk factors on COPD and lung cancer over time, and dependency of the risk of tuberculosis infection on the prevalence of disease. We quantified the sensitivity of our results to methods and data choices. FINDINGS: If smoking and solid-fuel use remain at current levels between 2003 and 2033, 65 million deaths from COPD and 18 million deaths from lung cancer are predicted in China; 82% of COPD deaths and 75% of lung cancer deaths will be attributable to the combined effects of smoking and solid-fuel use. Complete gradual cessation of smoking and solid-fuel use by 2033 could avoid 26 million deaths from COPD and 6.3 million deaths from lung cancer; interventions of intermediate magnitude would reduce deaths by 6-31% (COPD) and 8-26% (lung cancer). Complete cessation of smoking and solid-fuel use by 2033 would reduce the projected annual tuberculosis incidence in 2033 by 14-52% if 80% DOTS coverage is sustained, 27-62% if 50% coverage is sustained, or 33-71% if 20% coverage is sustained. INTERPRETATION: Reducing smoking and solid-fuel use can substantially lower predictions of COPD and lung cancer burden and would contribute to effective tuberculosis control in China. AD - Department of Epidemiology, Harvard School of Public Health, Boston, MA, USA. AN - 18835640 AU - Lin, H. H. AU - Murray, M. AU - Cohen, T. AU - Colijn, C. AU - Ezzati, M. DA - Oct 25 DO - 10.1016/S0140-6736(08)61345-8 ET - 10/07 J2 - Lancet KW - Air Pollution, Indoor/*adverse effects China/epidemiology Female Humans Lung Neoplasms/epidemiology/*etiology/mortality Male Meta-Analysis as Topic Prevalence Pulmonary Disease, Chronic Obstructive/epidemiology/*etiology/mortality Risk Factors Smoking/*adverse effects/epidemiology Tuberculosis/epidemiology/*etiology LA - eng M3 - Research Support, Non-U.S. Gov't N1 - Lin, Hsien-Ho Murray, Megan Cohen, Ted Colijn, Caroline Ezzati, Majid K08 AI055985-06/AI/NIAID NIH HHS/ England Lancet. 2008 Oct 25;372(9648):1473-83. Epub 2008 Oct 3. PY - 2008 RN - fulltext fulltext_1208 SN - 1474-547X (Electronic) 0140-6736 (Linking) SP - 1473-83 ST - Effects of smoking and solid-fuel use on COPD, lung cancer, and tuberculosis in China: a time-based, multiple risk factor, modelling study T2 - Lancet TI - Effects of smoking and solid-fuel use on COPD, lung cancer, and tuberculosis in China: a time-based, multiple risk factor, modelling study UR - http://www.ncbi.nlm.nih.gov/pubmed/18835640http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2652750/pdf/nihms-94728.pdf VL - 372 ID - 2535 ER - TY - JOUR AB - Case detection of an infectious individual and differentiation of infectiveness of a treated patient during two different stages of treatment are recognized as among key factors for the successful control and management of tuberculosis (TB) transmission. In this paper, a dynamic compartmental model is developed that incorporates these factors, and proofs are provided to show that the model's global dynamics are completely characterized by the control reproduction number, and in particular the disease eradication condition in terms of the case detection fraction is obtained, along with some numerical simulations. AD - Xian Jiaotong Univ, Sch Sci, Xian 710049, Peoples R China York Univ, Ctr Dis Modeling, Toronto, ON M3J 1P3, Canada York Univ, Dept Math & Stat, Toronto, ON M3J 1P3, Canada AN - WOS:000261427900016 AU - Liu, L. J. AU - Zhou, Y. C. AU - Wu, J. H. DO - 10.1216/Rmj-2008-38-5-1541 IS - 5 J2 - Rocky Mt J Math KW - tb model case detection relapse treatment m. tuberculosis mycobacterium-tuberculosis drug-resistance infection transmission reinfection epidemics LA - English N1 - Sp. Iss. SI 379wv Times Cited:9 Cited References Count:20 PY - 2008 SN - 0035-7596 SP - 1541-1559 ST - Global Dynamics in a Tb Model Incorporating Case Detection and Two Treatment Stages T2 - Rocky Mountain Journal of Mathematics TI - Global Dynamics in a Tb Model Incorporating Case Detection and Two Treatment Stages UR - ://WOS:000261427900016 https://projecteuclid.org/euclid.rmjm/1222088604 VL - 38 ID - 4846 ER - TY - JOUR AB - A co-epidemic arises when the spread of one infectious disease stimulates the spread of another infectious disease. Recently, this has happened with human immunodeficiency virus (HIV) and tuberculosis (TB). We develop two variants of a coepidemic model of two diseases. We calculate the basic reproduction number (R(0)), the disease-free equilibrium, and the quasi-disease-free equilibria, which we de. ne as the existence of one disease along with the complete eradication of the other disease, and the co-infection equilibria for specific conditions. We determine stability criteria for the disease-free and quasi-disease-free equilibria. We present an illustrative numerical analysis of the HIV-TB co-epidemics in India that we use to explore the effects of hypothetical prevention and treatment scenarios. Our numerical analysis demonstrates that exclusively treating HIV or TB may reduce the targeted epidemic, but can subsequently exacerbate the other epidemic. Our analyses suggest that coordinated treatment efforts that include highly active antiretroviral therapy for HIV, latent TB prophylaxis, and active TB treatment may be necessary to slow the HIV-TB co-epidemic. However, treatment alone may not be sufficient to eradicate both diseases. Increased disease prevention efforts (for example, those that promote condom use) may also be needed to extinguish this co-epidemic. Our simple model of two synergistic infectious disease epidemics illustrates the importance of including the effects of each disease on the transmission and progression of the other disease. AD - Yale Univ, Sch Management, New Haven, CT 06520 USA Los Alamos Natl Lab, Los Alamos, NM 87545 USA Stanford Univ, Dept Management Sci & Engn, Stanford, CA 94305 USA AN - WOS:000263565300004 AU - Long, E. F. AU - Vaidya, N. K. AU - Brandeau, M. L. DA - Nov-Dec DO - 10.1287/opre.1080.0571 IS - 6 J2 - Oper Res KW - united-states india impact therapy models transmission populations prevention hiv/aids driven LA - English N1 - 410gk Times Cited:17 Cited References Count:41 PY - 2008 SN - 0030-364x SP - 1366-1381 ST - Controlling Co-Epidemics: Analysis of HIV and Tuberculosis Infection Dynamics T2 - Operations Research TI - Controlling Co-Epidemics: Analysis of HIV and Tuberculosis Infection Dynamics UR - ://WOS:000263565300004 VL - 56 ID - 4847 ER - TY - JOUR AB - Molecular techniques such as IS6110-RFLP typing and spacer oligonucleotide typing (spoligotyping) have aided in understanding the transmission patterns of Mycobacterium tuberculosis. The degree of clustering of isolates on the basis of genotypes is informative of the extent of transmission in a given geographic area. We analyzed 130 published data sets of M. tuberculosis isolates, each representing a sample of bacterial isolates from a specific geographic region, typed with either or both of the IS6110-RFLP and spoligotyping methods. We explored common features and differences among these samples. Using population models, we found that the presence of large clusters (typically associated with recent transmission) as well as a large number of singletons (genotypes found exactly once in the data set) is consistent with an expanding infectious population. We also estimated the mutation rate of spoligotype patterns relative to IS6110 patterns and found the former rate to be about 10-26% of the latter. This study illustrates the utility of examining the full distribution of genotype cluster sizes from a given region, in the light of population genetic models. AU - Luciani, F. AU - Francis, A. R. AU - Tanaka, M. M. DO - 10.1016/j.meegid.2007.12.004 10.1016/j.meegid.2007.12.004. Epub 2008 Feb 1. IS - 2 KW - *Genotype *Oligonucleotides/chemistry Bacterial Typing Techniques/*methods Cluster Analysis DNA, Bacterial/analysis/genetics Evolution, Molecular Genetics, Population Models, Genetic Mutation Mycobacterium tuberculosis/*genetics/isolation & p Polymorphism, Restriction Fragment Length L1 - file:///C:/Users/James/AppData/Local/Mendeley Ltd/Mendeley Desktop/Downloaded/Luciani-2008-Interpreting genotype cluster siz.pdf PY - 2008 SN - 1567-1348 (Print) 1567-1348 (Linking) SP - 182-190 ST - Interpreting Genotype Cluster Sizes of Mycobacterium tuberculosis Isolates Typed with IS6110 and Spoligotyping T2 - Infect Genet Evol TI - Interpreting Genotype Cluster Sizes of Mycobacterium tuberculosis Isolates Typed with IS6110 and Spoligotyping UR - http://www.ncbi.nlm.nih.gov/pubmed/18243064 http://ac.els-cdn.com/S1567134807001980/1-s2.0-S1567134807001980-main.pdf?_tid=eb5abfc6-d108-11e4-9f77-00000aacb35d&acdnat=1427079876_82a807901e0a64a1115dc893a52728ab VL - 8 ID - 4115 ER - TY - JOUR AU - Magombedze, Gesham AU - Garira, Winston AU - Mwenje, Eddie DO - doi:10.1142/S0218339008002551 PY - 2008 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SP - 357-394 ST - IN-VIVO MATHEMATICAL STUDY OF CO-INFECTION DYNAMICS OF HIV-1 AND MYCOBACTERIUM TUBERCULOSIS T2 - Journal of Biological Systems TI - IN-VIVO MATHEMATICAL STUDY OF CO-INFECTION DYNAMICS OF HIV-1 AND MYCOBACTERIUM TUBERCULOSIS UR - http://www.worldscientific.com/doi/abs/10.1142/S0218339008002551 VL - 16 ID - 2536 ER - TY - JOUR AB - BACKGROUND: Recent approval of interferon-gamma release assays that are more specific for Mycobacterium tuberculosis has given new options for the diagnosis of latent tuberculosis infection (LTBI). OBJECTIVE: To assess the cost-effectiveness of Quanti-FERON-TB Gold (QFT-G) vs. the tuberculin skin test (TST) in diagnosing LTBI in contacts of active TB cases using a decision analytic Markov model. METHODS: Three screening strategies--TST alone, QFT-G alone and sequential screening of TST then QFT-G--were evaluated. The model was further stratified according to ethnicity and bacille Calmette-Guerin (BCG) vaccination status. Data sources included published studies and empirical data. Results were reported in terms of the incremental net monetary benefit (INMB) of each strategy compared with the baseline strategy of TST-based screening in all contacts. RESULTS: The most economically attractive strategy was to administer QFT-G in BCG-vaccinated contacts, and to reserve TST for all others (INMB CA$3.70/contact). The least cost-effective strategy was QFT-G for all contacts, which resulted in an INMB of CA$-11.50 per contact. Assuming a higher prevalence of recent infection, faster conversion of QFT-G, a higher rate of TB reactivation, reduction in utility or greater adherence to preventive treatment resulted in QFT-G becoming cost-effective in more subgroups. CONCLUSIONS: Selected use of QFT-G appears to be cost-effective if used in a targeted fashion. AD - University of British Columbia, Vancouver, British Columbia, Canada. carlo.marra@ubc.ca AU - Marra, F. AU - Marra, C. A. AU - Sadatsafavi, M. AU - Moran-Mendoza, O. AU - Cook, V. AU - Elwood, R. K. AU - Morshed, M. AU - Brunham, R. C. AU - Fitzgerald, J. M. KW - Adolescent Adult BCG Vaccine Canada Clinical Laboratory Techniques/economics Contact Tracing Cost-Benefit Analysis Humans Interferon-gamma/blood Markov Chains Middle Aged Sensitivity and Specificity Tuberculin Test/economics Tuberculosis/diagnosis Vaccination N1 - LR: 20111117; JID: 9706389; 0 (BCG Vaccine); 82115-62-6 (Interferon-gamma); ppublish PY - 2008 RN - fulltext fulltext_1208 SN - 1027-3719; 1027-3719 SP - 1414-1424 ST - Cost-effectiveness of a new interferon-based blood assay, QuantiFERON-TB Gold, in screening tuberculosis contacts T2 - The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease TI - Cost-effectiveness of a new interferon-based blood assay, QuantiFERON-TB Gold, in screening tuberculosis contacts VL - 12 Y2 - Dec ID - 2537 ER - TY - JOUR AB - A method for estimating the parameters of a model describing the main specifics of tuberculosis transmission in Russia is constructed in the paper. The method presented here allows one to take into account the difference of social and economic characteristics in the regions and the quality of work of antituberculous centers. The dynamics of the main epidemiological indices under possible changes of both socioeconomic characteristics and the quality of work of antituberculous centers is simulated. The results obtained show that an improvement in economic conditions may positively influence the epidemic situation diminishing the prevalence of disease. Regions with high epidemiological indices are the most sensitive to changes. AD - [Melnichenko, O. A.; Romanyukha, A. A.] Moscow MV Lomonosov State Univ, Dept Numer Math & Cybernet, Moscow 119992, Russia. Melnichenko, OA (reprint author), Moscow MV Lomonosov State Univ, Dept Numer Math & Cybernet, Moscow 119992, Russia. AN - WOS:000257264100004 AU - Melnichenko, O. A. AU - Romanyukha, A. A. DO - 10.1515/rjnamm.2008.004 IS - 1 J2 - Russ. J. Numer. Anal. Math. Model KW - Engineering Mathematics LA - English M3 - Article N1 - ISI Document Delivery No.: 320VV Times Cited: 2 Cited Reference Count: 7 Melnichenko, O. A. Romanyukha, A. A. 2 1 4 Walter de gruyter & co Berlin PY - 2008 SN - 0927-6467 SP - 63-75 ST - A model of tuberculosis epidemiology: estimation of parameters and analysis of factors influencing the dynamics of an epidemic process T2 - Russian Journal of Numerical Analysis and Mathematical Modelling TI - A model of tuberculosis epidemiology: estimation of parameters and analysis of factors influencing the dynamics of an epidemic process UR - ://WOS:000257264100004 VL - 23 ID - 6026 ER - TY - JOUR AB - BACKGROUND: Numerous patient and healthcare system-related delays contribute to the overall delay experienced by patients from onset of TB symptoms to diagnosis and treatment. Such delays are critical as infected individuals remain untreated in the community, providing more opportunities for transmission of the disease and adversely affecting the epidemic. METHODOLOGY/PRINCIPAL FINDINGS: We present an analysis of the factors that contribute to the overall delay in TB diagnosis and treatment, in a resource-poor setting. Impact on the distribution of diagnostic delay times was assessed for various factors, the sensitivity of the diagnostic method being found to be the most significant. A linear relationship was found between the sensitivity of the test and the predicted mean delay time, with an increase in test sensitivity resulting in a reduced mean delay time and a reduction in the drop-out rate. CONCLUSIONS/SIGNIFICANCE: The results show that in a developing country a number of delay factors, particularly the low sensitivity of the initial sputum smear microscopy test, potentially increase total diagnostic delay times experienced by TB patients significantly. The results reinforce the urgent need for novel diagnostic methods, both for smear positive and negative TB, that are highly sensitive, accessible and point of care, in order to reduce mean delay times. AD - DST/NRF Centre of Excellence for Epidemiological Modelling and Analysis (SACEMA), Stellenbosch University, Western Cape, Republic of South Africa. AN - 18398459 AU - Millen, S. J. AU - Uys, P. W. AU - Hargrove, J. AU - van Helden, P. D. AU - Williams, B. G. DO - 10.1371/journal.pone.0001933 [doi] DP - Nlm ET - 04/10 KW - Antitubercular Agents/therapeutic use Community Health Services/organization & administration Computer Simulation Developing Countries Health Services Accessibility Humans Patient Acceptance of Health Care Probability Risk Factors Sensitivity and Specificity Time Factors Tuberculosis/ diagnosis/ transmission LA - eng N1 - Millen, Stephen J Uys, Pieter W Hargrove, John van Helden, Paul D Williams, Brian G Research Support, Non-U.S. Gov't United States PloS one PLoS One. 2008 Apr 9;3(4):e1933. PY - 2008 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1932-6203 (Electronic) 1932-6203 (Linking) SP - e1933 ST - The effect of diagnostic delays on the drop-out rate and the total delay to diagnosis of tuberculosis T2 - PLoS One TI - The effect of diagnostic delays on the drop-out rate and the total delay to diagnosis of tuberculosis UR - http://www.plosone.org/article/fetchObjectAttachment.action?uri=info%3Adoi%2F10.1371%2Fjournal.pone.0001933&representation=PDF VL - 3 ID - 2538 ER - TY - JOUR AB - SETTING: The expansion of culture has been proposed to aid tuberculosis (TB) control in developing countries. OBJECTIVES: To examine the cost and cost-effectiveness at the Zambian National TB Reference Laboratory of homemade and commercially produced Lowenstein-Jensen culture (HLJ and CLJ) as well as automated and manually read liquid culture (AMGIT and MMGIT). DESIGN: Costs were estimated from the provider's perspective and based on the average monthly throughput. Cost-effectiveness estimates were based on yield during the study period. RESULTS: All techniques show comparable costs per culture (between US$28 and $32). Costs per Mycobacterium tuberculosis specimen detected were respectively US$197, $202, $312 and $340 for MMGIT, AMGIT, CLJ and HLJ. When modelled for the maximum throughput, costs were above US$95 per M. tuberculosis specimen detected for all techniques. When only performed among smear-negative specimens, costs per additionally identified M. tuberculosis would be US$487 for MMGIT and higher for other methods. CONCLUSION: Based on cost-effectiveness grounds, liquid media compare well with conventional solid media, especially where yield of MGIT is substantially higher than that of LJ media. The results indicate high overall costs per culture; the expansion of culture to decentralised levels with lower throughputs may result in even higher costs. AD - Health Economics and Financing Programme, Department of Public Health and Policy, London School of Hygiene & Tropical Medicine, London, UK. dirk.mueller@lshtm.ac.uk AN - 18812051 AU - Mueller, D. H. AU - Mwenge, L. AU - Muyoyeta, M. AU - Muvwimi, M. W. AU - Tembwe, R. AU - McNerney, R. AU - Godfrey-Faussett, P. AU - Ayles, H. M. DA - Oct ET - 09/25 KW - Bacteriological Techniques/*economics Cost-Benefit Analysis/*methods Costs and Cost Analysis Culture Media/economics Developing Countries Humans Mycobacterium tuberculosis/*isolation & purification Tuberculosis, Pulmonary/*diagnosis Zambia LA - eng N1 - Mueller, D H Mwenge, L Muyoyeta, M Muvwimi, M W Tembwe, R McNerney, R Godfrey-Faussett, P Ayles, H M Research Support, Non-U.S. Gov't France The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease Int J Tuberc Lung Dis. 2008 Oct;12(10):1196-202. PY - 2008 RN - fulltext fulltext_1208 SN - 1027-3719 (Print) 1027-3719 (Linking) SP - 1196-202 ST - Costs and cost-effectiveness of tuberculosis cultures using solid and liquid media in a developing country T2 - Int J Tuberc Lung Dis TI - Costs and cost-effectiveness of tuberculosis cultures using solid and liquid media in a developing country UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=18812051 VL - 12 ID - 2539 ER - TY - JOUR AB - We apply singularity analysis to a caricature of the simplified multistrain model of Castillo-Chavez and Feng (J Math Biol 35 (1997) 629-656) for the transmission of tuberculosis and the coupled two-stream vector-based model of Feng and Velasco-Hernandez (J Math Biol 35 (1997) 523-544) to identify values of the parameters for which the system of nonlinear first-order ordinary differential equations describing the model are integrable. A number of combinations of parameters for which the system is integrable are identified. We compare them with the results we obtained by a symmetry analysis in an earlier paper (J Math Anal Appl 333 (2007) 430-449. AD - [Nucci, M. C.] Univ Perugia, Dipartimento Matemat & Informat, I-06123 Perugia, Italy. [Leach, P. G. L.] Univ KwaZulu Natal, Sch Math Sci, ZA-4000 Durban, South Africa. Nucci, MC (reprint author), Univ Perugia, Dipartimento Matemat & Informat, I-06123 Perugia, Italy. nucci@unipg.it; leachp@nu.ac.za AN - WOS:000256889500003 AU - Nucci, M. C. AU - Leach, P. G. L. DA - Mar DO - 10.2991/jnmp.2008.15.1.3 IS - 1 J2 - J. Nonlinear Math. Phys. KW - ordinary differential-equations configurational invariants symmetries painleve Mathematics Physics L1 - internal-pdf://2961992493/Nucci-2008-Singularity analysis and integrabil.pdf LA - English M3 - Article N1 - ISI Document Delivery No.: 315OO Times Cited: 1 Cited Reference Count: 16 Nucci, M. C. Leach, P. G. L. Nucci, Maria Clara/B-3588-2012 Nucci, Maria Clara/0000-0003-1453-0988 1 0 2 Atlantis press Paris PY - 2008 SN - 1402-9251 SP - 22-34 ST - Singularity analysis and integrability of a simplified multistrain model for the transmission of tuberculosis and dengue fever T2 - Journal of Nonlinear Mathematical Physics TI - Singularity analysis and integrability of a simplified multistrain model for the transmission of tuberculosis and dengue fever UR - ://WOS:000256889500003 http://www.tandfonline.com/doi/pdf/10.2991/jnmp.2008.15.1.3?needAccess=true VL - 15 ID - 6014 ER - TY - JOUR AU - Okuonghae, Daniel AU - Aihie, Vincent DO - doi:10.1142/S0218339008002344 PY - 2008 RN - fulltext fulltext_1208 SP - 1-31 ST - CASE DETECTION AND DIRECT OBSERVATION THERAPY STRATEGY (DOTS) IN NIGERIA: ITS EFFECT ON TB DYNAMICS T2 - Journal of Biological Systems TI - CASE DETECTION AND DIRECT OBSERVATION THERAPY STRATEGY (DOTS) IN NIGERIA: ITS EFFECT ON TB DYNAMICS UR - http://www.worldscientific.com/doi/abs/10.1142/S0218339008002344 VL - 16 ID - 2540 ER - TY - JOUR AB - To aid the creation of novel antituberculosis (antiTB) compounds, Bayesian models were derived and validated on a data set of 3779 compounds which have been measured for minimum inhibitory concentration (MIC) in the Mycobacterium tuberculosis H37Rv strain. The model development and validation involved exploring six different training sets and 15 fingerprint types which resulted in a total of 90 models, with active compounds defined as those with MIC < 5 microM. The best model was derived using Extended Class Fingerprints of maximum diameter 12 (ECFP_12) and a few global descriptors on a training set derived using Functional Class Fingerprints of maximum diameter 4 (FCFP_4). This model demonstrated very good discriminant ability in general, with excellent discriminant statistics for the training set (total accuracy: 0.968; positive recall: 0.967) and a good predictive ability for the test set (total accuracy: 0.869; positive recall: 0.789). The good predictive ability was maintained when the model was applied to a well-separated test set of 2880 compounds derived from a commercial database (total accuracy: 0.73; positive recall: 0.72). The model revealed several conserved substructures present in the active and inactive compounds which are believed to have incremental and detrimental effects on the MIC, respectively. Strategies for enhancing the repertoire of antiTB compounds with the model, including virtual screening of large databases and combinatorial library design, are proposed. AD - Novartis Institute for Tropical Diseases, 10 Biopolis Road, #05-01 Chromos 138670, Singapore. AN - 19053518 AU - Prathipati, P. AU - Ma, N. L. AU - Keller, T. H. DA - Dec DO - 10.1021/ci800143n [doi] 10.1021/ci800143n [pii] DP - Nlm ET - 12/05 KW - Antitubercular Agents/ chemistry/ pharmacology Bayes Theorem Computer Simulation Databases, Factual Drug Design Drug Discovery/ statistics & numerical data Models, Chemical Mycobacterium tuberculosis/drug effects Quantitative Structure-Activity Relationship LA - eng N1 - Prathipati, Philip Ma, Ngai Ling Keller, Thomas H Validation Studies United States Journal of chemical information and modeling J Chem Inf Model. 2008 Dec;48(12):2362-70. PY - 2008 RN - fulltext fulltext_1208 SN - 1549-9596 (Print) 1549-9596 (Linking) SP - 2362-70 ST - Global Bayesian models for the prioritization of antitubercular agents T2 - J Chem Inf Model TI - Global Bayesian models for the prioritization of antitubercular agents UR - http://pubs.acs.org/doi/abs/10.1021/ci800143n VL - 48 ID - 2541 ER - TY - JOUR AB - During most infections, the population of immune cells known as macrophages are key to taking up and killing bacteria as an integral part of the immune response. However, during infection with Mycobacterium tuberculosis (Mtb), host macrophages serve as the preferred environment for mycobacterial growth. Further, killing of Mtb by macrophages is impaired unless they become activated. Activation is induced by stimulation from bacterial antigens and inflammatory cytokines derived from helper T cells. The key macrophage-activating cytokines in Mtb infection are tumor necrosis factor-alpha (TNF) and interferon (IFN)-gamma. Due to differences in cellular sources and secretion pathways for TNF and IFN-gamma, the possibility of heterogeneous cytokine distributions exists, suggesting that the timing of macrophage activation from these signals may affect activation kinetics and thus impact the outcome of Mtb infection. Here we use a mathematical model to show that negative feedback from production of nitric oxide (the key mediator of mycobacterial killing) that typically optimizes macrophage responses to activating stimuli may reduce effective killing of Mtb. Statistical sensitivity analysis predicts that if TNF and IFN-gamma signals precede infection, the level of negative feedback may have a strong effect on how effectively macrophages kill Mtb. However, this effect is relaxed when IFN-gamma or TNF+IFN-gamma signals are received coincident with infection. Under these conditions, the model suggests that negative feedback induces fast responses and an initial overshoot of nitric oxide production for given doses of TNF and IFN-gamma, favoring killing of Mtb. Together, our results suggest that direct entry of macrophages into a granuloma site (and not distal to it) from lung vascular sources represents a preferred host strategy for mycobacterial control. We examine implications of these results in establishment of latent Mtb infection. (c) 2008 Elsevier Ltd. All rights reserved. AD - Univ Michigan, Sch Med, Dept Microbiol & Immunol, Ann Arbor, MI 48109 USA Albert Einstein Coll Med, Dept Med, Bronx, NY 10461 USA Albert Einstein Coll Med, Dept Microbiol & Immunol, Bronx, NY 10461 USA AN - WOS:000256212500003 AU - Ray, J. C. J. AU - Wang, J. AU - Chan, J. AU - Kirschner, D. E. DA - May 7 DO - 10.1016/j.jtbi.2008.01.010 IS - 1 J2 - J Theor Biol KW - mathematical model cytokine immune system response time feedback nf-kappa-b necrosis-factor-alpha murine peritoneal-macrophages toll-like receptors interferon-gamma nitric-oxide oxidative stress iron-metabolism gene-expression reactive oxygen LA - English N1 - 305ya Times Cited:16 Cited References Count:64 PY - 2008 SN - 0022-5193 SP - 24-38 ST - The timing of TNF and IFN-gamma signaling affects macrophage activation strategies during Mycobacterium tuberculosis infection T2 - Journal of Theoretical Biology TI - The timing of TNF and IFN-gamma signaling affects macrophage activation strategies during Mycobacterium tuberculosis infection UR - ://WOS:000256212500003 VL - 252 ID - 2240 ER - TY - JOUR AB - OBJECTIVE AND DESIGN: The increased risk for tuberculosis in HIV-infected people has fueled a worldwide resurgence of tuberculosis. A major hindrance to controlling tuberculosis is the long treatment duration, leading to default, jeopardizing cure, and generating drug resistance. We investigated how tuberculosis is impacted by reducing treatment duration alone or combined with enhanced case detection and/or cure under different HIV prevalence levels. METHODS: Our model includes HIV stages I-IV and was calibrated to long-term tuberculosis and HIV data from Kenya. Benefits were assessed in terms of absolute and relative reductions in new tuberculosis cases and deaths. RESULTS: Compared with present-day strategies, at 3-20% HIV prevalence we attain a 6-20% decrease in incidence and mortality in 25 years when reducing treatment duration alone; benefits exceed 300% when combined with increased detection and cure. Benefits vary substantially according to HIV status and prevalence. Challenges arise because in absolute terms the number of infected people and deaths increases dramatically with increasing HIV prevalence, and because the relative efficacy of tuberculosis control policies displays a nonlinear pattern whereby they become less effective on a per capita basis at HIV prevalence levels greater than 15%. Benefits of reducing treatment duration may even be reversed at extreme HIV prevalence levels. Benefits of increasing cure versus detection increase as HIV prevalence increases. CONCLUSION: Reducing tuberculosis treatment duration, alone or in combination with other control strategies, can provide enormous benefits at high HIV prevalence. Tuberculosis control policies need to account for HIV levels because the efficacy of different interventions varies substantially with HIV prevalence. AD - Department of Environmental Science, policy and Management, University of California, Berkeley, California 94720-3114, USA. msanchez@nature.berkeley.edu AN - 18453856 AU - Sanchez, M. S. AU - Lloyd-Smith, J. O. AU - Porco, T. C. AU - Williams, B. G. AU - Borgdorff, M. W. AU - Mansoer, J. AU - Salomon, J. A. AU - Getz, W. M. DA - May 11 DO - 10.1097/QAD.0b013e3282f7cb4b ET - 05/06 J2 - Aids KW - AIDS-Related Opportunistic Infections/diagnosis/*drug therapy/epidemiology/prevention & control Antitubercular Agents/*administration & dosage/therapeutic use Drug Administration Schedule HIV Infections/epidemiology Humans Kenya/epidemiology Models, Biological Prevalence Treatment Outcome Tuberculosis/diagnosis/*drug therapy/epidemiology/prevention & control L1 - internal-pdf://1361299546/Sanchez-2008-Impact of HIV on novel therapies.pdf LA - eng M3 - Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't N1 - Sanchez, Maria S Lloyd-Smith, James O Porco, Travis C Williams, Brian G Borgdorff, Martien W Mansoer, John Salomon, Joshua A Getz, Wayne M England London, England AIDS. 2008 May 11;22(8):963-72. PY - 2008 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1473-5571 (Electronic) 0269-9370 (Linking) SP - 963-72 ST - Impact of HIV on novel therapies for tuberculosis control T2 - AIDS TI - Impact of HIV on novel therapies for tuberculosis control UR - http://www.ncbi.nlm.nih.gov/pubmed/18453856http://graphics.tx.ovid.com/ovftpdfs/FPDDNCGCICCHEG00/fs046/ovft/live/gv025/00002030/00002030-200805110-00007.pdf http://ovidsp.tx.ovid.com/ovftpdfs/FPDDNCIBLEEJED00/fs046/ovft/live/gv025/00002030/00002030-200805110-00007.pdf VL - 22 ID - 2542 ER - TY - JOUR AB - This paper addresses the synergistic interaction between HIV and mycobacterium tuberculosis using a deterministic model, which incorporates many of the essential biological and epidemiological features of the two dis- eases. In the absence of TB infection, the model (HIV-only model) is shown to have a globally asymptotically stable, disease-free equilibrium whenever the associated reproduction number is less than unity and has a unique endemic equilibrium whenever this number exceeds unity. On the other hand, the model with TB alone (TB-only model) undergoes the phenomenon of back- ward bifurcation, where the stable disease-free equilibrium co-exists with a stable endemic equilibrium when the associated reproduction threshold is less than unity. The analysis of the respective reproduction thresholds shows that the use of a targeted HIV treatment (using anti-retroviral drugs) strategy can lead to effective control of HIV provided it reduces the relative infectiousness of individuals treated (in comparison to untreated HIV-infected individuals) below a certain threshold. The full model, with both HIV and TB, is simulated to evaluate the impact of the various treatment strategies. It is shown that the HIV-only treatment strategy saves more cases of the mixed infection than the TB-only strategy. Further, for low treatment rates, the mixed-only strategy saves the least number of cases (of HIV, TB, and the mixed infection) in comparison to the other strategies. Thus, this study shows that if resources are limited, then targeting such resources to treating one of the diseases is more beneficial in reducing new cases of the mixed infection than targeting the mixed infection only diseases. Finally, the universal strategy saves more cases of the mixed infection than any of the other strategies. AD - Department of Mathematics, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada. AN - 18193936 AU - Sharomi, O. AU - Podder, C. N. AU - Gumel, A. B. AU - Song, B. DA - Jan DP - Nlm ET - 01/16 KW - Comorbidity Computer Simulation Disease Outbreaks/ prevention & control/ statistics & numerical data HIV Infections/ epidemiology/ prevention & control/transmission Humans Models, Biological Proportional Hazards Models Risk Assessment/ methods Risk Factors Treatment Outcome Tuberculosis/ epidemiology/ prevention & control/transmission LA - eng N1 - Sharomi, Oluwaseun Podder, Chandra N Gumel, Abba B Song, Baojun Research Support, Non-U.S. Gov't United States Mathematical biosciences and engineering : MBE Math Biosci Eng. 2008 Jan;5(1):145-74. PY - 2008 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1547-1063 (Print) 1547-1063 (Linking) SP - 145-74 ST - Mathematical analysis of the transmission dynamics of HIV/TB coinfection in the presence of treatment T2 - Math Biosci Eng TI - Mathematical analysis of the transmission dynamics of HIV/TB coinfection in the presence of treatment VL - 5 ID - 2544 ER - TY - JOUR AB - BACKGROUND: Travelers to countries with high tuberculosis incidence can acquire infection during travel. We sought to compare four screening interventions for travelers from low-incidence countries, who visit countries with varying tuberculosis incidence. METHODS: Decision analysis model: We considered hypothetical cohorts of 1,000 travelers, 21 years old, visiting Mexico, the Dominican Republic, or Haiti for three months. Travelers departed from and returned to the United States or Canada; they were born in the United States, Canada, or the destination countries. The time horizon was 20 years, with 3% annual discounting of future costs and outcomes. The analysis was conducted from the health care system perspective. Screening involved tuberculin skin testing (post-travel in three strategies, with baseline pre-travel tests in two), or chest radiography post-travel (one strategy). Returning travelers with tuberculin conversion (one strategy) or other evidence of latent tuberculosis (three strategies) were offered treatment. The main outcome was cost (in 2005 US dollars) per tuberculosis case prevented. RESULTS: For all travelers, a single post-trip tuberculin test was most cost-effective. The associated cost estimate per case prevented ranged from $21,406 for Haitian-born travelers to Haiti, to $161,196 for US-born travelers to Mexico. In all sensitivity analyses, the single post-trip tuberculin test remained most cost-effective. For US-born travelers to Haiti, this strategy was associated with cost savings for trips over 22 months. Screening was more cost-effective with increasing trip duration and infection risk, and less so with poorer treatment adherence. CONCLUSION: A single post-trip tuberculin skin test was the most cost-effective strategy considered, for travelers from the United States or Canada. The analysis did not evaluate the use of interferon-gamma release assays, which would be most relevant for travelers who received BCG vaccination after infancy, as in many European countries. Screening decisions should reflect duration of travel, tuberculosis incidence, and commitment to treat latent infection. AD - Respiratory Epidemiology Unit, Montreal Chest Institute, 3650 St, Urbain St,, Montreal, Quebec, H2X 2P4, Canada. michael_tan325@yahoo.com AN - 18534007 AU - Tan, M. AU - Menzies, D. AU - Schwartzman, K. DO - 10.1186/1471-2458-8-201 DP - Nlm ET - 06/07 J2 - BMC public health KW - Adult Canada/epidemiology Cost-Benefit Analysis Decision Support Techniques Disease Outbreaks/ prevention & control Dominican Republic Haiti Humans Incidence Markov Chains Mass Chest X-Ray/economics/statistics & numerical data Mass Screening/ economics/statistics & numerical data Mexico Skin Tests/economics/statistics & numerical data Travel/ statistics & numerical data Tuberculin Test Tuberculosis, Pulmonary/ epidemiology United States/epidemiology LA - eng N1 - Tan, Michael Menzies, Dick Schwartzman, Kevin England BMC Public Health. 2008 Jun 5;8:201. PY - 2008 RN - fulltext fulltext_1208 SN - 1471-2458 (Electronic) 1471-2458 (Linking) SP - 201 ST - Tuberculosis screening of travelers to higher-incidence countries: a cost-effectiveness analysis T2 - BMC Public Health TI - Tuberculosis screening of travelers to higher-incidence countries: a cost-effectiveness analysis UR - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2443799/pdf/1471-2458-8-201.pdf VL - 8 ID - 2545 ER - TY - JOUR AB - BACKGROUND: Contacts of patients with active tuberculosis ("TB contacts") with a tuberculin skin test (TST) size > or = 5 mm are currently recommended treatment for latent TB infection (LTBI). Knowing the cost-effectiveness of LTBI therapy for specific TB contact subpopulations may improve the use of limited resources by reducing the treatment of persons at low TB risk. OBJECTIVE: To evaluate the cost-effectiveness of LTBI therapy for different TB contact populations defined by important risk factors, and to propose an optimal policy based on different recommendation for each subgroup of contacts. METHODS: A 6-year Markov decision analytic model simulating the quality-adjusted life years (QALYs), number of active TB cases prevented, and costs for hypothetical cohorts of Canadian TB contacts defined by TST size, age group (< 10 y/o or above), ethnicity, closeness of contact, and Bacillus Calmette-Guerin (BCG) vaccination status. RESULTS: For the majority of subgroups, the current policy of preventive therapy in those with positive TST was the most cost-effective. Nevertheless, our analysis determined that LTBI treatment is not cost-effective in nonhousehold Canadian-born (nonaboriginal) or foreign-born contacts age > or = 10 y/o. On the other hand, empirical treatment without screening of all non-BCG-vaccinated household contacts age < 10 y/o appeared cost-effective. Such an optimal approach would result in an incremental net monetary benefit of $25 for each contact investigated for a willingness-to-pay of $50,000/QALY. Results were robust to several alternative assumptions considered in sensitivity analyses. CONCLUSIONS: The current practice of LTBI treatment for TB contacts with a TST size > or = 5 mm is cost-effective. A customized approach based on excluding low risk groups from screening and providing treatment to high risk contacts without screening could improve the performance of the program. AD - Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada. AN - 18489519 AU - Tan, M. C. AU - Marra, C. A. AU - Sadatsafavi, M. AU - Marra, F. AU - Moran-Mendoza, O. AU - Moadebi, S. AU - Elwood, R. K. AU - FitzGerald, J. M. DA - Sep-Oct DO - 10.1111/j.1524-4733.2008.00334.x DP - Nlm ET - 05/21 J2 - Value in health : the journal of the International Society for Pharmacoeconomics and Outcomes Research KW - Adolescent Adult Antitubercular Agents/ economics/therapeutic use British Columbia/epidemiology Child Child, Preschool Contact Tracing/ economics Cost-Benefit Analysis Female Humans Infant Infant, Newborn Male Markov Chains Models, Economic Quality-Adjusted Life Years Risk Factors Sensitivity and Specificity Tuberculin Test Tuberculosis, Pulmonary/drug therapy/ economics/epidemiology/transmission Young Adult LA - eng N1 - Tan, Michael C Marra, Carlo A Sadatsafavi, Mohsen Marra, Fawziah Moran-Mendoza, Onofre Moadebi, Susanne Elwood, R Kevin FitzGerald, J Mark United States Value Health. 2008 Sep-Oct;11(5):842-52. Epub 2008 Jul 15. PY - 2008 RN - fulltext fulltext_1208 SN - 1524-4733 (Electronic) 1098-3015 (Linking) SP - 842-52 ST - Cost-effectiveness of LTBI treatment for TB contacts in British Columbia T2 - Value Health TI - Cost-effectiveness of LTBI treatment for TB contacts in British Columbia UR - http://onlinelibrary.wiley.com/store/10.1111/j.1524-4733.2008.00334.x/asset/j.1524-4733.2008.00334.x.pdf?v=1&t=h6gegr4a&s=6e1abd0fd1fb12eaef44bdb058379457bdea0270 VL - 11 ID - 2546 ER - TY - JOUR AB - In a significant number of instances, an episode of tuberculosis can be attributed to a reinfection event. Because reinfection is more likely in high incidence regions than in regions of low incidence, more tuberculosis (TB) cases due to reinfection could be expected in high-incidence regions than in low-incidence regions. Empirical data from regions with various incidence rates appear to confirm the conjecture that, in fact, the incidence rate due to reinfection only, as a proportion of all cases, correlates with the logarithm of the incidence rate, rather than with the incidence rate itself. A theoretical model that supports this conjecture is presented. A Markov model was used to obtain a relationship between incidence and reinfection rates. It was assumed in this model that the rate of reinfection is a multiple, rho (the reinfection factor), of the rate of first-time infection, lambda. The results obtained show a relationship between the proportion of cases due to reinfection and the rate of incidence that is approximately logarithmic for a range of values of the incidence rate typical of those observed in communities across the globe. A value of rho is determined such that the relationship between the proportion of cases due to reinfection and the logarithm of the incidence rate closely correlates with empirical data. From a purely theoretical investigation, it is shown that a simple relationship can be expected between the logarithm of the incidence rates and the proportions of cases due to reinfection after a prior episode of TB. This relationship is sustained by a rate of reinfection that is higher than the rate of first-time infection and this latter consideration underscores the great importance of monitoring recovered TB cases for repeat disease episodes, especially in regions where TB incidence is high. Awareness of this may assist in attempts to control the epidemic. AD - DST/NRF Centre of Excellence for Excellence in Epidemiological Modelling and Analysis (SACEMA), Stellenbosch University, Stellenbosch, Western Cape 7602, Republic of South Africa. edserve@iafrica.com AN - 18577502 AU - Uys, P. W. AU - van Helden, P. D. AU - Hargrove, J. W. DA - Jan 6 DO - N48G734P015PV1JW [pii] 10.1098/rsif.2008.0184 [doi] DP - Nlm ET - 06/26 KW - Computer Simulation Humans Incidence Markov Chains Models, Theoretical Recurrence Tuberculosis/ epidemiology/ transmission LA - eng N1 - Uys, Pieter W van Helden, Paul D Hargrove, John W England Journal of the Royal Society, Interface / the Royal Society J R Soc Interface. 2009 Jan 6;6(30):11-5. PY - 2008 RN - fulltext fulltext_1208 SN - 1742-5689 (Print) 1742-5662 (Linking) SP - 11-5 ST - Tuberculosis reinfection rate as a proportion of total infection rate correlates with the logarithm of the incidence rate: a mathematical model T2 - J R Soc Interface TI - Tuberculosis reinfection rate as a proportion of total infection rate correlates with the logarithm of the incidence rate: a mathematical model UR - http://rsif.royalsocietypublishing.org/content/6/30/11.full.pdf VL - 6 ID - 2582 ER - TY - JOUR AB - OBJECTIVE: Tumor necrosis factor (TNF) blockade increases the risk of tuberculosis (TB). The purpose of this study was to use Markov modeling to examine the contributions of reactivation of latent tuberculous infection (LTBI) and the progression of new infection with Mycobacterium tuberculosis to active TB due to TNF blockade. These 2 pathogenic mechanisms cannot otherwise be readily distinguished. METHODS: Monte Carlo simulation was used to represent the range of reported values for the incidence of TB associated with infliximab (TNF monoclonal antibody) and etanercept (soluble TNF receptor) therapy. Iterative methods were then used to identify for each pair of incidence rates the Markov model parameters that most accurately represented the distribution of time to onset of TB as reported to the Food and Drug Administration. RESULTS: Modeling revealed an apparent median monthly rate of reactivation of LTBI by infliximab treatment of 20.8%, which was 12.1 times that with etanercept treatment (P<0.001). In contrast, both drugs appeared to pose a high risk of progression of new M tuberculosis infection to active TB. Progression of new infection appeared to cause nearly half of the etanercept-associated cases; it became the predominant cause of infliximab-associated cases only after the first year. CONCLUSION: Despite sharing a common therapeutic target, infliximab and etanercept differ markedly in the rates at which they reactivate LTBI. Confirmation of these findings will require the application of molecular epidemiologic tools to studies of TB in future biologics registries. Hidden Markov modeling and Monte Carlo simulation are powerful tools for revealing otherwise hidden aspects of the pathogenesis of TB. AD - PPD Inc., Washington, DC 20005, USA. robert.wallis@columbia.ppdi.com AN - 18383389 AU - Wallis, R. S. DA - Apr DO - 10.1002/art.23285 [doi] DP - Nlm ET - 04/03 KW - Antibodies, Monoclonal/ adverse effects Carrier State/immunology Humans Immunocompromised Host Immunoglobulin G/ adverse effects Immunologic Factors/ adverse effects Incidence Models, Theoretical Monte Carlo Method Receptors, Tumor Necrosis Factor Rheumatic Diseases/drug therapy Tuberculosis/ chemically induced/epidemiology/ immunology Tumor Necrosis Factor-alpha/ antagonists & inhibitors LA - eng N1 - Wallis, Robert S United States Arthritis and rheumatism Arthritis Rheum. 2008 Apr;58(4):947-52. PY - 2008 RN - fulltext fulltext_1208 SN - 0004-3591 (Print) 0004-3591 (Linking) SP - 947-52 ST - Mathematical modeling of the cause of tuberculosis during tumor necrosis factor blockade T2 - Arthritis Rheum TI - Mathematical modeling of the cause of tuberculosis during tumor necrosis factor blockade UR - http://onlinelibrary.wiley.com/store/10.1002/art.23285/asset/23285_ftp.pdf?v=1&t=h5w2ch1j&s=5239a0816f96e987fece13b26966f1ff1563b8ac VL - 58 ID - 2548 ER - TY - JOUR AB - This article describes the population pharmacokinetics of rifampin in South African pulmonary tuberculosis patients. Three datasets containing 2,913 rifampin plasma concentration-time data points, collected from 261 South African pulmonary tuberculosis patients aged 18 to 72 years and weighing 28.5 to 85.5 kg and receiving regular daily treatment that included administration of rifampin (450 to 600 mg) for at least 10 days, were pooled. A compartmental pharmacokinetic model was developed using nonlinear mixed-effects modeling. Variability in the shape of the absorption curve was described using a flexible transit compartment model, in which a delay in the onset of absorption and a gradually changing absorption rate were modeled as the passage of drug through a chain of hypothetical compartments, ultimately reaching the absorption compartment. A previously described implementation was extended to allow its application to multiple-dosing data. The typical population estimate of oral clearance was 19.2 liters x h(-1), while the volume of distribution was estimated to be 53.2 liters. Interindividual variability was estimated to be 52.8% for clearance and 43.4% for volume of distribution. Interoccasional variability was estimated for CL/F (22.5%) and mean transit time during absorption (67.9%). The use of single-drug formulations was found to increase both the mean transit time (by 104%) and clearance (by 23.6%) relative to fixed-dose-combination use. A strong correlation between clearance and volume of distribution suggested substantial variability in bioavailability, which could have clinical implications, given the dependence of treatment effectiveness on exposure. The final model successfully described rifampin pharmacokinetics in the population studied and is suitable for simulation in this context. AD - Division of Clinical Pharmacology, Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa. AN - 18391026 AU - Wilkins, J. J. AU - Savic, R. M. AU - Karlsson, M. O. AU - Langdon, G. AU - McIlleron, H. AU - Pillai, G. AU - Smith, P. J. AU - Simonsson, U. S. DA - Jun DO - AAC.00461-07 [pii] 10.1128/AAC.00461-07 [doi] DP - Nlm ET - 04/09 KW - Absorption Adolescent Adult Aged Antibiotics, Antitubercular/administration & dosage/ pharmacokinetics/therapeutic use Biological Availability Female Humans Male Metabolic Clearance Rate Middle Aged Models, Biological Rifampin/administration & dosage/ pharmacokinetics/therapeutic use South Africa Tuberculosis, Pulmonary/blood/ drug therapy/microbiology LA - eng N1 - Wilkins, Justin J Savic, Radojka M Karlsson, Mats O Langdon, Grant McIlleron, Helen Pillai, Goonaseelan Smith, Peter J Simonsson, Ulrika S H Research Support, Non-U.S. Gov't United States Antimicrobial agents and chemotherapy Antimicrob Agents Chemother. 2008 Jun;52(6):2138-48. Epub 2008 Apr 7. PY - 2008 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1098-6596 (Electronic) 0066-4804 (Linking) SP - 2138-48 ST - Population pharmacokinetics of rifampin in pulmonary tuberculosis patients, including a semimechanistic model to describe variable absorption T2 - Antimicrob Agents Chemother TI - Population pharmacokinetics of rifampin in pulmonary tuberculosis patients, including a semimechanistic model to describe variable absorption UR - http://aac.asm.org/content/52/6/2138.full.pdf VL - 52 ID - 2549 ER - TY - JOUR AB - Tuberculosis (TB) incidence rates vary substantially from regions to regions and from countries to countries. In countries such as Canada where TB incidence rate is low, increasing immigration trends may have significant impact on the TB transmission patterns in these countries. In this study we formulate a deterministic epidemiological model of TB transmission in two demographically distinct populations: Canadian born and foreign born populations, in order to investigate the effects of this demographic distinction on the short-term incidence and long-term transmission dynamics, and with special emphasis on the impact of immigration latent TB cases on the overall TB incidence rate in the whole population. AD - Department of Mathematics, Xi'an Jiaotong University, Xi'an 710049, China. zhouyc@mail.xjtu.edu.cn AN - 18656210 AU - Zhou, Y. AU - Khan, K. AU - Feng, Z. AU - Wu, J. DA - Sep 21 DO - S0022-5193(08)00271-3 [pii] 10.1016/j.jtbi.2008.05.026 [doi] DP - Nlm ET - 07/29 KW - Canada/epidemiology Disease Outbreaks Emigration and Immigration Forecasting Humans Incidence Models, Biological Models, Statistical Mycobacterium tuberculosis Tuberculosis/ epidemiology/transmission LA - eng N1 - Zhou, Yicang Khan, Kamran Feng, Zhilan Wu, Jianhong Research Support, Non-U.S. Gov't Netherlands Journal of theoretical biology J Theor Biol. 2008 Sep 21;254(2):215-28. Epub 2008 May 29. PY - 2008 RN - fulltext fulltext_1208 SN - 1095-8541 (Electronic) 0022-5193 (Linking) SP - 215-28 ST - Projection of tuberculosis incidence with increasing immigration trends T2 - J Theor Biol TI - Projection of tuberculosis incidence with increasing immigration trends UR - http://ac.els-cdn.com/S0022519308002713/1-s2.0-S0022519308002713-main.pdf?_tid=b394a83f5356d185ed29f48e419e68c9&acdnat=1345013792_8d9963f2787708670586453b53dfa93a VL - 254 ID - 2550 ER - TY - BILL AB - Bacterial persistent infections are responsible for a significant amount of the human morbidity and mortality. Unlike acute bacterial infections, it is very difficult to treat persistent bacterial infections (e.g. tuberculosis). Knowledge about the location of pathogenic bacteria during persistent infection will help to treat such conditions by designing novel drugs which can reach such locations. In this study, events of bacterial persistent infections were analyzed using game theory. A game was defined where the pathogen and the host are the two players with a conflict of interest. Criteria for the establishment of Nash equilibrium were calculated for this game. This theoretical model, which is very simple and heuristic, predicts that during persistent infections pathogenic bacteria stay in both intracellular and extracellular compartments of the host. The result of this study implies that a bacterium should be able to survive in both intracellular and extracellular compartments of the host in order to cause persistent infections. This explains why persistent infections are more often caused by intracellular pathogens like Mycobacterium and Salmonella. Moreover, this prediction is in consistence with the results of previous experimental studies. AD - Centre for Infectious Disease Research and Biosafety Laboratories, Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India. sandeep@mcbl.iisc.ernet.in AN - 19401783 DA - Jan 1 KW - Models: Biological Game Theory Bacteria Extracellular Space Intracellular Space Humans Bacterial Infections Host-Pathogen Interactions LB - p31798 M1 - 4 PY - 2009 RN - fulltext fulltext_1208 SP - e5383 ST - Location of pathogenic bacteria during persistent infections: insights from an analysis using game theory T2 - PLoS ONE TI - Location of pathogenic bacteria during persistent infections: insights from an analysis using game theory UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=19401783 VL - 4 ID - 2567 ER - TY - BILL AB - The Global Plan to Stop TB calls for significant financial resources to meet the Millennium Development Goals for tuberculosis. However, it is unclear whether the economic benefits of TB control exceed the costs. Using an epidemiological model, we find that the economic benefits of the Global Plan relative to sustained DOTS (a commonly used treatment method) were unambiguously greater than the incremental costs in all nine high-burden countries in Africa and in Afghanistan, Pakistan, and Russia. Benefit-cost ratios of sustaining DOTS at current levels relative to having no DOTS exceeded 1 in all twenty-two high-burden, TB-endemic countries and sub-Saharan Africa. AD - Resources for the Future, Washington, D.C., USA. ramanan@rff.org AN - 19567413 DA - Jan 1 KW - Africa South of the Sahara Directly Observed Therapy Cost-Benefit Analysis Tuberculosis Humans Health Care Costs LB - p30434 M1 - 4 PY - 2009 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SP - w730-42 ST - Global investments in TB control: economic benefits T2 - Health Aff (Millwood) TI - Global investments in TB control: economic benefits UR - http://content.healthaffairs.org/content/28/4/w730.longhttp://content.healthaffairs.org/content/28/4/w730.full.pdf VL - 28 ID - 2575 ER - TY - JOUR AB - The Bill and Melinda Gates Foundation supports an ambitious portfolio of novel vaccines, drug regimens, and diagnostic tools for tuberculosis (TB). We elicited the expected efficacies and improvements of the novel interventions in discussions with the foundations managing their development. Using an age-structured mathematical model of TB, we explored the potential benefits of novel interventions under development and those not yet in the portfolio, focusing on the WHO Southeast Asia region. Neonatal vaccination with the portfolio vaccine decreases TB incidence by 39% to 52% by 2050. Drug regimens that shorten treatment duration and are efficacious against drug-resistant strains reduce incidence by 10-27%. New diagnostics reduce incidence by 13-42%. A triple combination of a portfolio vaccine, drug regimen, and diagnostics reduces incidence by 71%. A short mass vaccination catch-up campaign, not yet in the portfolio, to augment the triple combination, accelerates the decrease, preventing >30% more cases by 2050 than just the triple combination. New vaccines and drug regimens targeted at the vast reservoir of latently infected people, not in the portfolio, would reduce incidence by 37% and 82%, respectively. The combination of preventive latent therapy and a 2-month drug treatment regimen reduces incidence by 94%. Novel technologies in the pipeline would achieve substantial reductions in TB incidence, but not the Stop TB Partnership target for elimination. Elimination will require new delivery strategies, such as mass vaccination campaigns, and new products targeted at latently infected people. AD - Vaccine and Infectious Disease Institute, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA. AN - 19666590 AU - Abu-Raddad, L. J. AU - Sabatelli, L. AU - Achterberg, J. T. AU - Sugimoto, J. D. AU - Longini, I. M., Jr. AU - Dye, C. AU - Halloran, M. E. DA - Aug 18 DO - 0901720106 [pii] 10.1073/pnas.0901720106 [doi] DP - Nlm ET - 08/12 KW - Antitubercular Agents/ therapeutic use Asia, Southeastern Combined Modality Therapy/methods Disease Progression Humans Immunization Programs Models, Theoretical Prevalence Public Health Reproducibility of Results Time Factors Tuberculosis/diagnosis/drug therapy/ epidemiology/prevention & control Tuberculosis Vaccines/ therapeutic use World Health LA - eng N1 - Abu-Raddad, Laith J Sabatelli, Lorenzo Achterberg, Jerusha T Sugimoto, Jonathan D Longini, Ira M Jr Dye, Christopher Halloran, M Elizabeth T32 HD007543-10/HD/NICHD NIH HHS/United States Research Support, Non-U.S. Gov't United States Proceedings of the National Academy of Sciences of the United States of America Proc Natl Acad Sci U S A. 2009 Aug 18;106(33):13980-5. Epub 2009 Aug 3. PY - 2009 RN - fulltext fulltext_1208 SN - 1091-6490 (Electronic) 0027-8424 (Linking) SP - 13980-5 ST - Epidemiological benefits of more-effective tuberculosis vaccines, drugs, and diagnostics T2 - Proc Natl Acad Sci U S A TI - Epidemiological benefits of more-effective tuberculosis vaccines, drugs, and diagnostics UR - http://www.pnas.org/content/106/33/13980.full.pdf VL - 106 ID - 2551 ER - TY - JOUR AB - BACKGROUND: A mathematical model was designed to explore the impact of three strategies for better tuberculosis case finding. Strategies included: (1) reducing the number of tuberculosis patients who do not seek care; (2) reducing diagnostic delay; and (3) engaging non-DOTS providers in the referral of tuberculosis suspects to DOTS services in the Indonesian health system context. The impact of these strategies on tuberculosis mortality and treatment outcome was estimated using a mathematical model of the Indonesian health system. METHODS: The model consists of multiple compartments representing logical movement of a respiratory symptomatic (tuberculosis suspect) through the health system, including patient- and health system delays. Main outputs of the model are tuberculosis death rate and treatment outcome (i.e. full or partial cure). We quantified the model parameters for the Jogjakarta province context, using a two round Delphi survey with five Indonesian tuberculosis experts. RESULTS: The model validation shows that four critical model outputs (average duration of symptom onset to treatment, detection rate, cure rate, and death rate) were reasonably close to existing available data, erring towards more optimistic outcomes than are actually reported. The model predicted that an intervention to reduce the proportion of tuberculosis patients who never seek care would have the biggest impact on tuberculosis death prevention, while an intervention resulting in more referrals of tuberculosis suspects to DOTS facilities would yield higher cure rates. This finding is similar for situations where the alternative sector is a more important health resource, such as in most other parts of Indonesia. CONCLUSION: We used mathematical modeling to explore the impact of Indonesian health system interventions on tuberculosis treatment outcome and deaths. Because detailed data were not available regarding the current Indonesian population, we relied on expert opinion to quantify the parameters. The fact that the model output showed similar results to epidemiological data suggests that the experts had an accurate understanding of this subject, thereby reassuring the quality of our predictions. The model highlighted the potential effectiveness of active case finding of tuberculosis patients with limited access to DOTS facilities in the developing country setting. AD - Department of Public Health, Faculty of Medicine, Gadjah Mada University, Jogjakarta, Indonesia. risandono.ahmad@gmail.com AN - 19505296 AU - Ahmad, R. A. AU - Mahendradhata, Y. AU - Cunningham, J. AU - Utarini, A. AU - de Vlas, S. J. DO - 1471-2334-9-87 [pii] 10.1186/1471-2334-9-87 [doi] DP - Nlm ET - 06/10 KW - Computer Simulation Delphi Technique Humans Indonesia/epidemiology Models, Theoretical Outcome Assessment (Health Care) Patient Acceptance of Health Care Tuberculosis/ epidemiology/prevention & control LA - eng N1 - Ahmad, Riris A Mahendradhata, Yodi Cunningham, Jane Utarini, Adi de Vlas, Sake J Research Support, Non-U.S. Gov't England BMC infectious diseases BMC Infect Dis. 2009 Jun 8;9:87. PY - 2009 RN - fulltext fulltext_1208 SN - 1471-2334 (Electronic) 1471-2334 (Linking) SP - 87 ST - How to optimize tuberculosis case finding: explorations for Indonesia with a health system model T2 - BMC Infect Dis TI - How to optimize tuberculosis case finding: explorations for Indonesia with a health system model UR - http://www.biomedcentral.com/1471-2334/9/87 VL - 9 ID - 2552 ER - TY - JOUR AB - BACKGROUND: BCG vaccine protects against the severe forms of tuberculosis (TB) in children. Several low-prevalence countries are reviewing their policy, usually shifting from universal vaccination to vaccination of infants in high-risk groups only. We combined an epidemiologic analysis with a cost-effectiveness analysis to evaluate the cost-effectiveness of targeted strategies. METHODS: We fitted a static model to the data to estimate vaccine efficacy and risk of disease. We applied our method to the Dutch situation, analyzing severe TB cases in high-risk group children age 0-5, between 1996 and 2003. We considered the current strategy targeting immigrant children from high-incidence countries, and a proposed strategy additionally targeting children from 3 lower-incidence, but higher-immigration, countries. RESULTS: In the absence of vaccination, the annual risk of developing severe TB for a child in the current target group is 3/100,000, while BCG vaccination reduces this risk by 73%. Therefore about 9000 children would need to be vaccinated to prevent 1 case. Vaccinating children from high-incidence countries would then cost about Euro 4,500 per discounted disability-adjusted life year averted. In the extended target group, the risk of disease is somewhat lower with a similar vaccine effectiveness, so costs are raised. CONCLUSIONS: The current Dutch BCG strategy, as well as the proposed inclusion of immigrant children from Turkey, Surinam and former Yugoslavia, is on average cost-effective. However, the low number of both vaccinated and unvaccinated severe TB cases leads to broad confidence intervals on vaccine efficacy, highlighting the difficulty associated with decision-making in low-prevalence settings. AD - Department of Infectious Diseases Epidemiology, National Institute for Public Health and the Environment, Bilthoven, The Netherlands. hester.korthals.altes@rivm.nl AN - 19295437 AU - Altes, H. K. AU - Dijkstra, F. AU - Lugner, A. AU - Cobelens, F. AU - Wallinga, J. DO - 10.1097/EDE.0b013e31819e3c1a ET - 03/20 KW - BCG Vaccine/*therapeutic use Child, Preschool Cost-Benefit Analysis Humans Immunization Programs/*economics/methods/organization & administration Infant Infant, Newborn Netherlands/epidemiology *Severity of Illness Index Tuberculosis/epidemiology/physiopathology/*prevention & control LA - eng N1 - Altes, Hester Korthals Dijkstra, Frederika Lugner, Anna Cobelens, Frank Wallinga, Jacco United States Epidemiology (Cambridge, Mass.) Epidemiology. 2009 Jul;20(4):562-8. PY - 2009 RN - fulltext fulltext_1208 SN - 1531-5487 (Electronic) 1044-3983 (Linking) SP - 562-568 ST - Targeted BCG vaccination against severe tuberculosis in low-prevalence settings: epidemiologic and economic assessment T2 - Epidemiology TI - Targeted BCG vaccination against severe tuberculosis in low-prevalence settings: epidemiologic and economic assessment UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=19295437http://graphics.tx.ovid.com/ovftpdfs/FPDDNCGCAGHAJF00/fs047/ovft/live/gv024/00001648/00001648-200907000-00015.pdf VL - 20 ID - 2553 ER - TY - JOUR AB - The strengths and limitations of using homogeneous mixing and heterogeneous mixing epidemic models are explored in the context of the transmission dynamics of tuberculosis. The focus is on three types of models: a standard incidence homogeneous mixing model, a non-homogeneous mixing model that incorporates 'household' contacts, and an age-structured model. The models are parameterized using demographic and epidemiological data and the patterns generated from these models are compared. Furthermore, the effects of population growth, stochasticity, clustering of contacts, and age structure on disease dynamics are explored. This framework is used to asses the possible causes for the observed historical decline of tuberculosis notifications. AD - School of Science and Technology, Universidad Metropolitana, San Juan 00928-1150, Puerto Rico. juan.p.aparicio@gmail.com AN - 19364150 AU - Aparicio, J. P. AU - Castillo-Chavez, C. DA - Apr DP - Nlm ET - 04/15 KW - Age Distribution Biometry/ methods Computer Simulation Data Interpretation, Statistical Disease Outbreaks/ statistics & numerical data Humans Incidence Models, Biological Population Dynamics Proportional Hazards Models Risk Assessment/methods Risk Factors Survival Analysis Survival Rate Tuberculosis/ mortality LA - eng N1 - Aparicio, Juan Pablo Castillo-Chavez, Carlos Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. United States Mathematical biosciences and engineering : MBE Math Biosci Eng. 2009 Apr;6(2):209-37. PY - 2009 RN - fulltext fulltext_1208 SN - 1547-1063 (Print) 1547-1063 (Linking) SP - 209-37 ST - Mathematical modelling of tuberculosis epidemics T2 - Math Biosci Eng TI - Mathematical modelling of tuberculosis epidemics VL - 6 ID - 2554 ER - TY - JOUR AB - Extensively drug-resistant tuberculosis (XDR TB) has been detected in most provinces of South Africa, particularly in the KwaZulu-Natal province where several hundred cases have been reported since 2004. We analyzed the transmission dynamics of XDR TB in the region using mathematical models, and observed that nosocomial transmission clusters of XDR TB may emerge into community-based epidemics under the public health conditions of many South African communities. The effective reproductive number of XDR TB in KwaZulu-Natal may be around 2. Intensified community-based case finding and therapy appears critical to curtailing transmission. In the setting of delayed disease presentation and high system demand, improved diagnostic approaches may need to be employed in community-based programs rather than exclusively at tertiary hospitals. Using branching process mathematics, we observed that early, community-based drug-susceptibility testing and effective XDR therapy could help curtail ongoing transmission and reduce the probability of XDR TB epidemics in neighboring territories. AD - Tugela Ferry Care and Research Collaboration, Tugela Ferry, KwaZulu-Natal 3010, South Africa. sanjay.basu@yale.edu AN - 19365076 AU - Basu, S. AU - Friedland, G. H. AU - Medlock, J. AU - Andrews, J. R. AU - Shah, N. S. AU - Gandhi, N. R. AU - Moll, A. AU - Moodley, P. AU - Sturm, A. W. AU - Galvani, A. P. DA - May 5 DO - 0812472106 [pii] 10.1073/pnas.0812472106 [doi] DP - Nlm ET - 04/15 KW - Disease Outbreaks/ prevention & control Humans Models, Biological South Africa/epidemiology Tuberculosis, Multidrug-Resistant/ epidemiology/ prevention & control/transmission L1 - internal-pdf://0349054559/Basu-2009-Averting epidemics of extensively dr.pdf LA - eng N1 - Basu, Sanjay Friedland, Gerald H Medlock, Jan Andrews, Jason R Shah, N Sarita Gandhi, Neel R Moll, Anthony Moodley, Prashini Sturm, A Willem Galvani, Alison P R36/PHS HHS/United States T32/PHS HHS/United States Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. United States Proceedings of the National Academy of Sciences of the United States of America Proc Natl Acad Sci U S A. 2009 May 5;106(18):7672-7. Epub 2009 Apr 13. PY - 2009 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1091-6490 (Electronic) 0027-8424 (Linking) SP - 7672-7 ST - Averting epidemics of extensively drug-resistant tuberculosis T2 - Proc Natl Acad Sci U S A TI - Averting epidemics of extensively drug-resistant tuberculosis UR - http://www.pnas.org/content/106/18/7672.full.pdf https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2678614/pdf/zpq7672.pdf VL - 106 ID - 2555 ER - TY - JOUR AB - The evolution of Mycobacterium tuberculosis presents several challenges for public health. HIV and resistance to antimycobacterial medications have evolutionary implications for how Mycobacterium tuberculosis will evolve, as these factors influence the host environment and transmission dynamics of tuberculosis strains. We present an evolutionary invasion analysis of tuberculosis that characterizes the direction of tuberculosis evolution in the context of different natural and human-driven selective pressures, including changes in tuberculosis treatment and HIV prevalence. We find that the evolution of tuberculosis virulence can be affected by treatment success rates, the relative transmissibility of emerging strains, the rate of reactivation from latency among hosts, and the life expectancy of hosts. We find that the virulence of tuberculosis strains may also increase as a consequence of rising HIV prevalence, requiring faster case detection strategies in areas where the epidemics of HIV and tuberculosis collide. AD - Department of Epidemiology and Public Health, Yale University School of Medicine, 60 College Street, New Haven, CT 06520, USA. sanjay.basu@yale.edu AN - 19172358 AU - Basu, S. AU - Galvani, A. P. DO - 10.1007/s11538-009-9394-x KW - *Biological Evolution Drug Resistance, Bacterial/genetics HIV Infections/complications Humans Mathematical Concepts Mutation Mycobacterium tuberculosis/drug effects/genetics/*pathogenicity Selection, Genetic Tuberculosis/complications/drug therapy/*microbiology Virulence/genetics LA - eng N1 - Basu, Sanjay Galvani, Alison P United States Bulletin of mathematical biology Bull Math Biol. 2009 Jul;71(5):1073-88. Epub 2009 Jan 27. PY - 2009 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1522-9602 (Electronic) 0092-8240 (Linking) SP - 1073-1088 ST - The evolution of tuberculosis virulence T2 - Bulletin of Mathematical Biology TI - The evolution of tuberculosis virulence UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=19172358http://www.springerlink.com/content/a214u21283449170/http://www.springerlink.com/content/a214u21283449170/?MUD=MP https://link.springer.com/article/10.1007%2Fs11538-009-9394-x VL - 71 ID - 2556 ER - TY - JOUR AB - BACKGROUND: Isoniazid preventive treatment (IPT) has been recommended for human immunodeficiency virus (HIV) infected individuals. OBJECTIVE/DESIGN: We used a mathematical model to simulate the benefits and risks of preventive treatment delivered through antiretroviral (ARV) clinics using clinical data from Botswana. RESULTS: Preventive treatment was found to reduce the incidence of tuberculosis (TB) by at least 12 cases per 100000 population per year versus the scenario without such treatment over a 50-year simulation. Isoniazid (INH) resistant TB was observed to increase by <1% per year, even when using pessimistic assumptions about resistance emergence. The use of tuberculin skin testing had little impact as a screening procedure, while secondary treatment was observed to nearly double the impact of a preventive treatment program. Regardless of whether or not preventive treatment was implemented, INH-resistant TB rose in the context of increasing HIV prevalence, but was minimally amplified by preventive treatment itself. CONCLUSIONS: IPT programs implemented through ARV clinics may be effective at reducing TB incidence. The resistance contribution of IPT appears unlikely to supersede its overall incidence and mortality benefits. AD - Department of Epidemiology & Public Health, Yale University School of Medicine, New Haven, Connecticut, USA. sanjay.basu@yale.edu AN - 19383201 AU - Basu, S. AU - Maru, D. AU - Poolman, E. AU - Galvani, A. DA - May ET - 04/23 J2 - The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease KW - Anti-Retroviral Agents/*therapeutic use Antitubercular Agents/*therapeutic use Botswana/epidemiology Drug Therapy, Combination HIV Infections/complications/epidemiology/*prevention & control Hospitals, Special Humans Incidence Mass Screening/methods Models, Theoretical *Practice Guidelines as Topic Prevalence Primary Prevention/*standards Secondary Prevention/*standards Treatment Outcome Tuberculosis/epidemiology/*prevention & control L1 - internal-pdf://0848659591/s21.pdf LA - eng M3 - Comparative Study N1 - Basu, S Maru, D Poolman, E Galvani, A France Int J Tuberc Lung Dis. 2009 May;13(5):652-8. PY - 2009 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1027-3719 (Print) 1027-3719 (Linking) SP - 652-8 ST - Primary and secondary tuberculosis preventive treatment in HIV clinics: simulating alternative strategies T2 - Int J Tuberc Lung Dis TI - Primary and secondary tuberculosis preventive treatment in HIV clinics: simulating alternative strategies UR - http://www.ncbi.nlm.nih.gov/pubmed/19383201 VL - 13 ID - 2557 ER - TY - JOUR AB - A two strain tuberculosis model with treatment which allows TB patients with the drug sensitive of strain Mycobacterium tuberculosis to be cured is presented. The model is further extended to incorporate quarantine for active TB cases with multi?drug resistant TB strains. The model assumes that latently infected individuals develop active disease as a result of endogenous activation and exogenous reinfection. Qualitative analysis of the model including positivity, boundedness and persistence of solutions are presented. The thresholds and equilibria quantities for the models are determined and stability of the solution is analyzed. From the study we conclude that quarantine of the multi?drug resistant tuberculosis cases reduces the multi?drug resistant tuberculosis induced reproduction number to values below unit, thus this intervention strategy can control the development of multi?drug resistant tuberculosis epidemic. Also effective chemoprophylaxis and treatment of infectives result in a reduction of multi?drug resistant tuberculosis cases since most multi?drug resistant tuberculosis cases are a result of inappropriate treatment. AU - Bhunu, C. P. AU - Garira, W. DA - 2009/01/01 DO - 10.3846/1392-6292.2009.14.291-312 L1 - internal-pdf://0181572430/Bhunu-2009-A two strain tuberculosis transmiss.pdf PY - 2009 RN - fulltext fulltext_1208 SN - 1392-6292 SP - 291-312 ST - A two strain tuberculosis transmission model with therapy and quarantine T2 - Mathematical Modelling and Analysis TI - A two strain tuberculosis transmission model with therapy and quarantine UR - http://www.tandfonline.com/doi/abs/10.3846/1392-6292.2009.14.291-312 http://www.tandfonline.com/doi/pdf/10.3846/1392-6292.2009.14.291-312?needAccess=true VL - 14 Y2 - 2012/08/10 ID - 2558 ER - TY - JOUR AB - An HIV/AIDS and TB coinfection model which considers antiretroviral therapy for the AIDS cases and treatment of all forms of TB, i.e., latent and active forms of TB, is presented. We begin by presenting an HIV/AIDS-TB coinfection model and analyze the TB and HIV/AIDS submodels separately without any intervention strategy. The TB-only model is shown to exhibit backward bifurcation when its corresponding reproduction number is less than unity. On the other hand, the HIV/AIDS-only model has a globally asymptotically stable disease-free equilibrium when its corresponding reproduction number is less than unity. We proceed to analyze the full HIV-TB coinfection model and extend the model to incorporate antiretroviral therapy for the AIDS cases and treatment of active and latent forms of TB. The thresholds and equilibria quantities for the models are determined and stabilities analyzed. From the study we conclude that treatment of AIDS cases results in a significant reductions of numbers of individuals progressing to active TB. Further, treatment of latent and active forms of TB results in delayed onset of the AIDS stage of HIV infection. AD - Modeling Biomedical Systems Research Group, Department of Applied Mathematics, National University of Science and Technology, P.O. Box AC 939 Ascot, Bulawayo, Zimbabwe. cpbhunu1762@nust.ac.zw AN - 19475456 AU - Bhunu, C. P. AU - Garira, W. AU - Mukandavire, Z. DA - Oct DO - 10.1007/s11538-009-9423-9 [doi] DP - Nlm ET - 05/29 KW - AIDS-Related Opportunistic Infections/drug therapy/epidemiology Acquired Immunodeficiency Syndrome/ complications/drug therapy/ epidemiology/transmission Algorithms Anti-Retroviral Agents/therapeutic use Antitubercular Agents/therapeutic use Basic Reproduction Number Computer Simulation HIV Infections/ complications/drug therapy/ epidemiology/transmission HIV Seropositivity/drug therapy/epidemiology/transmission Humans Models, Biological Tuberculosis/ complications/drug therapy/ epidemiology/transmission LA - eng N1 - Bhunu, C P Garira, W Mukandavire, Z Research Support, N.I.H., Extramural United States Bulletin of mathematical biology Bull Math Biol. 2009 Oct;71(7):1745-80. Epub 2009 May 28. PY - 2009 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1522-9602 (Electronic) 0092-8240 (Linking) SP - 1745-80 ST - Modeling HIV/AIDS and tuberculosis coinfection T2 - Bull Math Biol TI - Modeling HIV/AIDS and tuberculosis coinfection UR - http://www.springerlink.com/content/d3g7732k83772416/ VL - 71 ID - 2559 ER - TY - JOUR AB - This paper deals with the global properties of a tuberculosis model with mass action incidence and two differential infectivity. The direct Lyapunov method enables us to prove that the considered model is globally stable: There is always a globally asymptotically stable equilibrium state. Depending on the value of the basic reproduction number R-0, this state can be either endemic (R-0 > 1), or infection-free (R-0 <= 1). Numerical results are provided to illustrate analytical results. (C) 2009 Elsevier B.V. All rights reserved. AD - Univ Douala, Fac Sci, Dept Math & Comp Sci, Lab Appl Math, Douala, Cameroon Univ Yaounde 1, Dept Math & Phys, Natl High Sch Polytech, Yaounde, Cameroon AN - WOS:000266896800033 AU - Bowong, S. AU - Tewa, J. J. DA - Nov DO - 10.1016/j.cnsns.2009.02.017 IS - 11 J2 - Commun Nonlinear Sci KW - lyapunov functions stability epidemiological models tuberculosis global asymptotic stability heterogeneous populations disease transmission lyapunov functions systems dynamics seir LA - English N1 - 457al Times Cited:23 Cited References Count:33 PY - 2009 SN - 1007-5704 SP - 4010-4021 ST - Mathematical analysis of a tuberculosis model with differential infectivity T2 - Communications in Nonlinear Science and Numerical Simulation TI - Mathematical analysis of a tuberculosis model with differential infectivity UR - ://WOS:000266896800033 VL - 14 ID - 4849 ER - TY - JOUR AB - OBJECTIVE: To assess the cost-effectiveness of screening for latent tuberculosis infection (LTBI) using a commercially available detection test and treating individuals at high risk for human immunodeficiency virus (HIV) infection in a middle-income country. DESIGN: We developed a Markov model to evaluate the cost per LTBI case detected, TB case averted and quality-adjusted life year (QALY) gained for a cohort of 1000 individuals at high risk for HIV infection over 20 years. Baseline model inputs for LTBI prevalence were obtained from published literature and cross-sectional data from tuberculosis (TB) screening using QuantiFERON-TB Gold In-Tube (QFT-GIT) testing among sex workers and illicit drug users at high risk for HIV recruited through street outreach in Tijuana, Mexico. Costs are reported in 2007 US dollars. Future costs and QALYs were discounted at 3% per year. Sensitivity analyses were performed to evaluate model robustness. RESULTS: Over 20 years, we estimate the program would prevent 78 cases of active TB and 55 TB-related deaths. The incremental cost per case of LTBI detected was US$730, cost per active TB averted was US$529 and cost per QALY gained was US$108. CONCLUSIONS: In settings of endemic TB and escalating HIV incidence, targeting LTBI screening and treatment among high-risk groups may be highly cost-effective. AD - Division of Global Public Health, School of Medicine, University of California San Diego, San Diego, California 92093-0507, USA. jlburgos@ucsd.edu AU - Burgos, J. L. AU - Kahn, J. G. AU - Strathdee, S. A. AU - Valencia-Mendoza, A. AU - Bautista-Arredondo, S. AU - Laniado-Laborin, R. AU - Castaneda, R. AU - Deiss, R. AU - Garfein, R. S. KW - Comorbidity Cost-Benefit Analysis HIV Infections/epidemiology Humans Markov Chains Mass Screening/economics Mexico/epidemiology Monte Carlo Method Quality-Adjusted Life Years Tuberculosis/diagnosis/economics/epidemiology/therapy N1 - LR: 20110517; GR: R01 DA019829/DA/NIDA NIH HHS/United States; GR: R01 DA019829-03/DA/NIDA NIH HHS/United States; GR: R01 DA023877-02S2/DA/NIDA NIH HHS/United States; GR: R01 DA023877-S1/DA/NIDA NIH HHS/United States; GR: T32 A107384/PHS HHS/United States; GR: T32 AI007384-17/AI/NIAID NIH HHS/United States; GR: T32 AI007384-18/AI/NIAID NIH HHS/United States; GR: T32 DA023356-04/DA/NIDA NIH HHS/United States; JID: 9706389; NIHMS136277; OID: NLM: NIHMS136277; OID: NLM: PMC2763545; ppublish PY - 2009 RN - fulltext fulltext_1208 SN - 1027-3719; 1027-3719 SP - 962-968 ST - Targeted screening and treatment for latent tuberculosis infection using QuantiFERON-TB Gold is cost-effective in Mexico T2 - The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease TI - Targeted screening and treatment for latent tuberculosis infection using QuantiFERON-TB Gold is cost-effective in Mexico UR - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2763545/pdf/nihms136277.pdf VL - 13 Y2 - Aug ID - 2560 ER - TY - JOUR AB - Background: Tuberculosis (TB) remains an important public health problem in Canadian Aboriginal (First Nations and Inuit) communities. The objectives of this study were to predict future disease burden and set feasible targets for the elimination of TB in the First Nations population, using retrospective data and an epidemic model. Methods: Reported TB incidence data (1974-2002), previously published TB meningitis data from the pre-chemotherapy era, and previous estimates of disease risk following infection were used to estimate a trend in the annual risk of infection from 1929 to 2002, and the age-specific prevalence of infection in 2002. A state-transfer, compartmental model was then developed to predict future disease burden. Two scenarios were simulated, with different disease risk parameters. Results: The estimated prevalence of infection in 2002 was 20.9% in scenario 1 and 25.5% in scenario 2. Predicted incidence rates in 2015 were 16.8 per 100 000 and 11.7 per 100 000 for the two scenarios, respectively. The incidence of disease was not tower than 1 per 100 000 for either scenario in 2034, the arbitrarily chosen last year of the model. Conclusions: The goal of eliminating TB among Aboriginal peoples in Canada is a feasible one, but will only be achieved with continued investment in programs designed to control and prevent transmission. Reactivation disease cases may occur for a number of years to come, making rapid elimination a difficult goal. (C) 2008 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved. AD - [Clark, Michael] Childrens Hosp Eastern Ontario, Dept Pediat, Ottawa, ON K1H 8L1, Canada. [Cameron, D. William] Univ Ottawa, Dept Med, Div Infect Dis, Ottawa, ON, Canada. Clark, M (reprint author), Childrens Hosp Eastern Ontario, Dept Pediat, 401 Smyth Rd, Ottawa, ON K1H 8L1, Canada. mclar018@uottawa.ca AN - WOS:000264707200018 AU - Clark, M. AU - Cameron, D. W. DA - Mar DO - 10.1016/j.ijid.2008.06.021 IS - 2 J2 - Int. J. Infect. Dis. KW - Tuberculosis model Canada mycobacterium-tuberculosis control strategies tubercle-bacilli calmette-guerin annual risk infection meningitis children alberta disease Infectious Diseases LA - English M3 - Article N1 - ISI Document Delivery No.: 426KM Times Cited: 4 Cited Reference Count: 33 Clark, Michael Cameron, D. William Cameron, Bill/0000-0002-0090-3539 4 0 5 Elsevier sci ltd Oxford PY - 2009 SN - 1201-9712 SP - 220-226 ST - Tuberculosis elimination in the Canadian First Nations population: assessment by a state-transfer, compartmental epidemic model T2 - International Journal of Infectious Diseases TI - Tuberculosis elimination in the Canadian First Nations population: assessment by a state-transfer, compartmental epidemic model UR - ://WOS:000264707200018 VL - 13 ID - 5935 ER - TY - JOUR AB - Recent reports of extensively drug-resistant TB in South Africa have renewed concerns that antibiotic resistance may undermine progress in TB control. We review three major questions for which mathematical models elucidate the epidemiology and control of drug-resistant TB. How is multiple drug-resistant Mycobacterium tuberculosis selected for in individuals exposed to combination chemotherapy? What factors determine the prevalence of drug-resistant TB? Which interventions to prevent the spread of drug-resistant TB are effective and feasible? Models offer insight into the acquisition and amplification of drug resistance, reveal the importance of distinguishing the intrinsic and extrinsic determinants of the reproductive capacity of drug-resistant M. tuberculosis, and demonstrate the cost effectiveness of interventions for drug-resistant TB. These models also highlight knowledge gaps for which new research will improve our ability to project trends of drug resistance and develop more effective policies for its control. AD - Division of Global Health Equity, Brigham and Women's Hospital, Boston, MA, USA and Department of Epidemiology, Harvard School of Public Health, 677 Huntington Avenue, Boston, MA 02115, USA. tcohen@hsph.harvard.edu. AN - 20477283 AU - Cohen, T. AU - Dye, C. AU - Colijn, C. AU - Williams, B. AU - Murray, M. DA - Feb DO - 10.1586/17476348.3.1.67 ET - 2009/02/01 IS - 1 J2 - Expert review of respiratory medicine LA - eng N1 - Cohen, Ted Dye, Christopher Colijn, Caroline Williams, Brian Murray, Megan England Expert Rev Respir Med. 2009 Feb;3(1):67-79. doi: 10.1586/17476348.3.1.67. PY - 2009 SN - 1747-6356 (Electronic) 1747-6348 (Linking) SP - 67-79 ST - Mathematical models of the epidemiology and control of drug-resistant TB T2 - Expert Rev Respir Med TI - Mathematical models of the epidemiology and control of drug-resistant TB UR - http://www.ncbi.nlm.nih.gov/pubmed/20477283 VL - 3 ID - 4501 ER - TY - JOUR AB - Metabolism is central to cell physiology, and metabolic disturbances play a role in numerous disease states. Despite its importance, the ability to study metabolism at a global scale using genomic technologies is limited. In principle, complete genome sequences describe the range of metabolic reactions that are possible for an organism, but cannot quantitatively describe the behaviour of these reactions. We present a novel method for modeling metabolic states using whole cell measurements of gene expression. Our method, which we call E-Flux (as a combination of flux and expression), extends the technique of Flux Balance Analysis by modeling maximum flux constraints as a function of measured gene expression. In contrast to previous methods for metabolically interpreting gene expression data, E-Flux utilizes a model of the underlying metabolic network to directly predict changes in metabolic flux capacity. We applied E-Flux to Mycobacterium tuberculosis, the bacterium that causes tuberculosis (TB). Key components of mycobacterial cell walls are mycolic acids which are targets for several first-line TB drugs. We used E-Flux to predict the impact of 75 different drugs, drug combinations, and nutrient conditions on mycolic acid biosynthesis capacity in M. tuberculosis, using a public compendium of over 400 expression arrays. We tested our method using a model of mycolic acid biosynthesis as well as on a genome-scale model of M. tuberculosis metabolism. Our method correctly predicts seven of the eight known fatty acid inhibitors in this compendium and makes accurate predictions regarding the specificity of these compounds for fatty acid biosynthesis. Our method also predicts a number of additional potential modulators of TB mycolic acid biosynthesis. E-Flux thus provides a promising new approach for algorithmically predicting metabolic state from gene expression data. AD - Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America. C.Colijn@bristol.ac.uk AN - 19714220 AU - Colijn, C. AU - Brandes, A. AU - Zucker, J. AU - Lun, D. S. AU - Weiner, B. AU - Farhat, M. R. AU - Cheng, T. Y. AU - Moody, D. B. AU - Murray, M. AU - Galagan, J. E. DA - Aug DO - 10.1371/journal.pcbi.1000489 [doi] DP - Nlm ET - 08/29 KW - Algorithms Cluster Analysis Computational Biology/methods Fatty Acids/chemistry Gene Expression Profiling/ methods Gene Expression Regulation Gene Expression Regulation, Bacterial Genome, Bacterial Metabolic Networks and Pathways/genetics Models, Biological Models, Statistical Mycobacterium tuberculosis/ metabolism Mycolic Acids/ chemistry Reproducibility of Results Software LA - eng N1 - Colijn, Caroline Brandes, Aaron Zucker, Jeremy Lun, Desmond S Weiner, Brian Farhat, Maha R Cheng, Tan-Yun Moody, D Branch Murray, Megan Galagan, James E 1U19AI076217/AI/NIAID NIH HHS/United States HHSN 26620040000IC/PHS HHS/United States R01 071155/PHS HHS/United States Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't United States PLoS computational biology PLoS Comput Biol. 2009 Aug;5(8):e1000489. Epub 2009 Aug 28. PY - 2009 RN - fulltext fulltext_1208 SN - 1553-7358 (Electronic) 1553-734X (Linking) SP - e1000489 ST - Interpreting expression data with metabolic flux models: predicting Mycobacterium tuberculosis mycolic acid production T2 - PLoS Comput Biol TI - Interpreting expression data with metabolic flux models: predicting Mycobacterium tuberculosis mycolic acid production UR - http://www.ploscompbiol.org/article/fetchObjectAttachment.action?uri=info%3Adoi%2F10.1371%2Fjournal.pcbi.1000489&representation=PDF VL - 5 ID - 2561 ER - TY - JOUR AB - BACKGROUND: Interferon gamma release assays (IGRAs) offer alternatives to tuberculin skin tests (TSTs) for diagnosing latent tuberculosis infection (LTBI). Unlike TSTs, IGRAs require only a single patient visit and are not affected by prior BCG vaccination, providing greater specificity. Of 2 Food and Drug Administration-approved IGRAs, the newer QuantiFERON-TB Gold in Tube test (QFT-GIT) requires less manual processing time than the QuantiFERON-TB Gold test (QFT-G). We compared the cost-effectiveness of the QFT-G, QFT-GIT, and TST for detecting LTBI in new health care workers (HCWs). METHODS: A Markov state-transition decision analytic model using the societal perspective and lifetime horizon was constructed to compare costs and quality-adjusted life-years (QALYs) associated with the 3 strategies for hypothetical 35-year-old HCWs with or without prior BCG vaccination. Direct and indirect costs and probabilities were based on manufacturer data, national Veterans Health Administration records, and the published literature. Future costs and QALYs were discounted at 3% per year. RESULTS: Both IGRAs were more effective and less costly than the TST, whether or not the HCW had been vaccinated with BCG previously. The incremental cost-effectiveness ratio of the QFT-G compared with the QFT-GIT was $14,092/QALY for non-BCG-vaccinated HCWs and $103,047/QALY for BCG-vaccinated HCWs. There was no prevalence of LTBI at which the TST became the most effective or least costly strategy. If the sensitivity of the QFT-GIT exceeds that of the QFT-G, then the QFT-GIT is the most effective and least costly strategy. CONCLUSION: Use of the QFT-G and QFT-GIT leads to superior clinical outcomes and lower costs than the TST and should be considered in screening non-BCG-vaccinated and BCG-vaccinated new HCWs for LTBI. AD - Division of Infectious Diseases, University of Cincinnati College of Medicine, 231 Albert Sabin Way, Box 670560, Cincinnati, OH 45267, USA. deperiom@hotmail.com AU - de Perio, M. A. AU - Tsevat, J. AU - Roselle, G. A. AU - Kralovic, S. M. AU - Eckman, M. H. DO - 10.1001/archinternmed.2008.524 KW - Antigens, Bacterial Cost-Benefit Analysis Enzyme-Linked Immunosorbent Assay Female Health Personnel Humans Interferon-gamma/blood/secretion Leukocytes/metabolism Male Mass Screening Sensitivity and Specificity Tuberculin Test/economics Tuberculosis/diagnosis/economics N1 - LR: 20090729; JID: 0372440; 0 (Antigens, Bacterial); 82115-62-6 (Interferon-gamma); CIN: Arch Intern Med. 2009 Jul 27;169(14):1336; author reply 1336-7. PMID: 19636037; ppublish PY - 2009 RN - fulltext fulltext_1208 SN - 1538-3679; 0003-9926 SP - 179-187 ST - Cost-effectiveness of interferon gamma release assays vs tuberculin skin tests in health care workers T2 - Archives of Internal Medicine TI - Cost-effectiveness of interferon gamma release assays vs tuberculin skin tests in health care workers UR - http://archinte.jamanetwork.com/article.aspx?articleid=414724 VL - 169 Y2 - Jan 26 ID - 2563 ER - TY - JOUR AB - OBJECTIVES: There is only limited economic data in head-to head comparison between a whole blood QuantiFERON TB Gold in tube (QFT) and the tuberculin skin test (TST) when screening and treating for latent tuberculosis infection (LTBI), and no published study to date that takes into account the predictive value of the two tests. METHODS: Health and economic outcomes of isoniazid preventive treatment (IPT) of close contacts were compared in a decision tree model to perform a cost-benefit analysis with respect to isoniazid related hepatotoxicity and early post-exposure TB over a 2-y period, using the QFT or TST alone or QFT as a confirmatory test for TST results. RESULTS: Cost of screening and treating for using the QFT alone amounted to euro215.79 per close contact, less than that of dual step-testing (euro227.89) or using TST alone (euro232.58). Savings amounted to euro12,200 or euro16,791 per 1000 close contacts, respectively. QFT based procedures were most sensitive to low compliance with IPT or increasing price. Costs of dual step screening was mostly influenced by cost of treating TB disease. When the progression rate for QFT was lowered to that for the TST in a sensitivity analysis, the relationship between the strategies remained robust. In addition, costs of the QFT strategy decreased to euro165.1, and those of the dual step strategy to euro218.4. CONCLUSION: IPT on the basis of using the QFT assay alone produces less cost and reduces more TB cases than other strategies in a low-incidence setting. These data have implications for the rational implementation of screening strategies in contact investigation. AD - Department of Pneumology, Medical School Hannover (MHH), Carl-Neuberg-Str.1, 30625 Hannover, Germany. Diel.Roland@mhh-hannover.de AU - Diel, R. AU - Schaberg, T. AU - Loddenkemper, R. AU - Welte, T. AU - Nienhaus, A. DO - 10.1016/j.rmed.2009.07.008 KW - Antitubercular Agents/economics/therapeutic use Cost-Benefit Analysis Epidemiologic Methods Germany Humans Isoniazid/economics/therapeutic use Latent Tuberculosis/economics/prevention & control Tuberculin Test/economics/methods N1 - JID: 8908438; 0 (Antitubercular Agents); 54-85-3 (Isoniazid); 2009/06/10 [received]; 2009/07/03 [revised]; 2009/07/10 [accepted]; 2009/08/13 [aheadofprint]; ppublish PY - 2009 RN - fulltext fulltext_1208 SN - 1532-3064; 0954-6111 SP - 1838-1853 ST - Enhanced cost-benefit analysis of strategies for LTBI screening and INH chemoprevention in Germany T2 - Respiratory medicine TI - Enhanced cost-benefit analysis of strategies for LTBI screening and INH chemoprevention in Germany UR - http://ac.els-cdn.com/S0954611109002285/1-s2.0-S0954611109002285-main.pdf?_tid=983026d6-6b36-11e2-b95a-00000aacb35d&acdnat=1359589480_2444bddb27af2d8dcf3910d59109b1c7 VL - 103 Y2 - Dec ID - 2564 ER - TY - JOUR AB - OBJECTIVE: To investigate whether short-term annual declines of 5-10% in the incidence of tuberculosis (TB) can be sustained over the long term by maintaining high case detection rates (CDRs). METHODS: We constructed a compartmental difference-equation model of a TB epidemic in a hypothetical population of constant size with a treatment success rate of 85%. The impact of CDR on TB incidence was then investigated by generating an equilibrium population with no TB case detection and increasing the smear-positive CDR under two scenarios: (i) rapid expansion by 10% per year to a CDR of 80% after 8 years, and (ii) gradual expansion by 1% per year to a CDR of 90% after 90 years. The model was applied in two hypothetical populations: one without HIV and the other with a stable HIV incidence representative of the African Region. The CDR for smear-negative TB was assumed to be a constant fraction of the smear-positive CDR. FINDINGS: In the absence of a TB control programme, the projected annual incidence of TB was 513 cases per 100 000 population, with a point prevalence of 1233 per 100 000 and an annual TB-specific mortality rate of 182 per 100 000. Immediately increasing the TB CDR from 0% to 70% caused a 74% reduction in TB incidence within 10 years. However, once case detection stabilized at any constant level < 80%, projected TB incidence also stabilized. Ten years after a CDR of 70% was reached, the annual decline in TB incidence was < 1.5%, regardless of how rapidly case detection was scaled up and despite wide variation of all model parameters. CONCLUSION: While improved CDRs have a dramatic short-term effect on TB incidence, maintaining those rates, even at current target levels, may not reduce long-term incidence by more than 1-2% per year. TB control programmes and researchers should vigorously pursue improvements in case detection, regardless of current CDRs. AD - Center for Tuberculosis Research, Johns Hopkins University, 1550 Orleans Street, Baltimore, MD 21221, USA. AN - 19551238 AU - Dowdy, D. W. AU - Chaisson, R. E. DA - Apr ET - 06/25 J2 - Bulletin of the World Health Organization KW - Disease Outbreaks HIV Infections/epidemiology/microbiology Humans *Models, Biological Sputum/microbiology Tuberculosis/*epidemiology/microbiology/therapy/virology LA - eng M3 - Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't N1 - Dowdy, David W Chaisson, Richard E K24 AI 01637/AI/NIAID NIH HHS/ T32 GM07309/GM/NIGMS NIH HHS/ Switzerland Bull World Health Organ. 2009 Apr;87(4):296-304. PY - 2009 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1564-0604 (Electronic) 0042-9686 (Linking) SP - 296-304 ST - The persistence of tuberculosis in the age of DOTS: reassessing the effect of case detection T2 - Bull World Health Organ TI - The persistence of tuberculosis in the age of DOTS: reassessing the effect of case detection UR - http://www.ncbi.nlm.nih.gov/pubmed/19551238http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2672581/pdf/08-054510.pdf VL - 87 ID - 2565 ER - TY - JOUR AB - BACKGROUND: Culture of Mycobacterium tuberculosis currently represents the closest "gold standard" for diagnosis of tuberculosis (TB), but operational data are scant on the impact and cost-effectiveness of TB culture for human immunodeficiency (HIV-) infected individuals in resource-limited settings. METHODOLOGY/PRINCIPAL FINDINGS: We recorded costs, laboratory results, and dates of initiating TB therapy in a centralized TB culture program for HIV-infected patients in Rio de Janeiro, Brazil, constructing a decision-analysis model to estimate the incremental cost-effectiveness of TB culture from the perspective of a public-sector TB control program. Of 217 TB suspects presenting between January 2006 and March 2008, 33 (15%) had culture-confirmed active tuberculosis; 23 (70%) were smear-negative. Among smear-negative, culture-positive patients, 6 (26%) began TB therapy before culture results were available, 11 (48%) began TB therapy after culture result availability, and 6 (26%) did not begin TB therapy within 180 days of presentation. The cost per negative culture was US$17.52 (solid media)-$23.50 (liquid media). Per 1,000 TB suspects and compared with smear alone, TB culture with solid media would avert an estimated eight TB deaths (95% simulation interval [SI]: 4, 15) and 37 disability-adjusted life years (DALYs) (95% SI: 13, 76), at a cost of $36 (95% SI: $25, $50) per TB suspect or $962 (95% SI: $469, $2642) per DALY averted. Replacing solid media with automated liquid culture would avert one further death (95% SI: -1, 4) and eight DALYs (95% SI: -4, 23) at $2751 per DALY (95% SI: $680, dominated). The cost-effectiveness of TB culture was more sensitive to characteristics of the existing TB diagnostic system than to the accuracy or cost of TB culture. CONCLUSIONS/SIGNIFICANCE: TB culture is potentially effective and cost-effective for HIV-positive patients in resource-constrained settings. Reliable transmission of culture results to patients and integration with existing systems are essential. AD - Center for Tuberculosis Research, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA. AN - 19129940 AU - Dowdy, D. W. AU - Lourenco, M. C. AU - Cavalcante, S. C. AU - Saraceni, V. AU - King, B. AU - Golub, J. E. AU - Bishai, D. AU - Durovni, B. AU - Chaisson, R. E. AU - Dorman, S. E. DO - 10.1371/journal.pone.0004057 ET - 01/09 J2 - PloS one KW - AIDS-Related Opportunistic Infections/*diagnosis Bacteriological Techniques/*economics Brazil Cost-Benefit Analysis HIV Infections/*complications Humans Mycobacterium tuberculosis/*isolation & purification Tuberculosis/*diagnosis LA - eng M3 - Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't N1 - Dowdy, David W Lourenco, Maria C Cavalcante, Solange C Saraceni, Valeria King, Bonnie Golub, Jonathan E Bishai, David Durovni, Betina Chaisson, Richard E Dorman, Susan E 5 T32 GMO7309/PHS HHS/ K23 AI 51528/AI/NIAID NIH HHS/ K24 AI 16137/AI/NIAID NIH HHS/ PLoS One. 2008;3(12):e4057. Epub 2008 Dec 29. PY - 2009 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1932-6203 (Electronic) 1932-6203 (Linking) SP - e4057 ST - Impact and cost-effectiveness of culture for diagnosis of tuberculosis in HIV-infected Brazilian adults T2 - PLoS One TI - Impact and cost-effectiveness of culture for diagnosis of tuberculosis in HIV-infected Brazilian adults UR - http://www.ncbi.nlm.nih.gov/pubmed/19129940http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2614861/pdf/pone.0004057.pdf VL - 3 ID - 2524 ER - TY - JOUR AB - The growing number of reports of antibiotic resistance worldwide has led to fears that some lethal human pathogens, such as Mycobacterium tuberculosis, will soon become untreatable. Here, we show that, although this is possible, it is not inevitable. The World Health Organization has recently reported more cases of multidrug-resistant tuberculosis than ever before, but a new analysis of trend data for 10 groups of countries shows how and why the spread of multidrug-resistant tuberculosis can be reversed by good treatment practices. We find that multidrug-resistant tuberculosis is not self-sustaining in 9 out of the 10 settings and conclude that multidrug-resistant tuberculosis can be set on a path-albeit a slow path-to elimination. This result applies even to countries such as Estonia and Latvia, which have exceptionally high prevalence rates of multidrug-resistant tuberculosis. AD - Dye, C WHO, Off HIV AIDS TB Malaria & Neglected Trop Dis, CH-1211 Geneva 27, Switzerland WHO, Off HIV AIDS TB Malaria & Neglected Trop Dis, CH-1211 Geneva 27, Switzerland WHO, Off HIV AIDS TB Malaria & Neglected Trop Dis, CH-1211 Geneva 27, Switzerland STIAS, S African Ctr Epidemiol Modelling & Anal, ZA-7602 Stellenbosch, South Africa AN - ISI:000277196700001 AU - Dye, C. AU - Williams, B. G. DA - Oct 21 DO - ARTN 3ra8 DOI 10.1126/scitranslmed.3000346 J2 - Sci Transl Med KW - mycobacterium-tuberculosis drug-resistance mutations emergence epidemics dynamics cohort period risks L1 - internal-pdf://0619070107/3ra8.full.pdf LA - English N1 - 590AW Times Cited:3 Cited References Count:34 PY - 2009 RN - fulltext fulltext_1208 SN - 1946-6234 ST - Slow Elimination of Multidrug-Resistant Tuberculosis T2 - Science Translational Medicine TI - Slow Elimination of Multidrug-Resistant Tuberculosis UR - ://000277196700001http://stm.sciencemag.org/content/1/3/3ra8 VL - 1 ID - 2566 ER - TY - JOUR AB - BACKGROUND: Because metabolism is fundamental in sustaining microbial life, drugs that target pathogen-specific metabolic enzymes and pathways can be very effective. In particular, the metabolic challenges faced by intracellular pathogens, such as Mycobacterium tuberculosis, residing in the infected host provide novel opportunities for therapeutic intervention. RESULTS: We developed a mathematical framework to simulate the effects on the growth of a pathogen when enzymes in its metabolic pathways are inhibited. Combining detailed models of enzyme kinetics, a complete metabolic network description as modeled by flux balance analysis, and a dynamic cell population growth model, we quantitatively modeled and predicted the dose-response of the 3-nitropropionate inhibitor on the growth of M. tuberculosis in a medium whose carbon source was restricted to fatty acids, and that of the 5'-O-(N-salicylsulfamoyl) adenosine inhibitor in a medium with low-iron concentration. CONCLUSION: The predicted results quantitatively reproduced the experimentally measured dose-response curves, ranging over three orders of magnitude in inhibitor concentration. Thus, by allowing for detailed specifications of the underlying enzymatic kinetics, metabolic reactions/constraints, and growth media, our model captured the essential chemical and biological factors that determine the effects of drug inhibition on in vitro growth of M. tuberculosis cells. AD - Biotechnology HPC Software Applications Institute, Telemedicine and Advanced Technology Research Center, U,S, Army Medical Research and Materiel Command, Ft, Detrick, MD 21702, USA. xfang@bioanalysis.org AN - 19754970 AU - Fang, X. AU - Wallqvist, A. AU - Reifman, J. DO - 1752-0509-3-92 [pii] 10.1186/1752-0509-3-92 [doi] DP - Nlm ET - 09/17 KW - Bacterial Proteins/ metabolism Cell Proliferation/drug effects Cell Survival/drug effects Computer Simulation Models, Biological Mycobacterium tuberculosis/drug effects/ metabolism Nitro Compounds/ administration & dosage Propionic Acids/ administration & dosage Signal Transduction/drug effects/ physiology Succinate Dehydrogenase/ antagonists & inhibitors Systems Biology/ methods LA - eng N1 - Fang, Xin Wallqvist, Anders Reifman, Jaques Research Support, U.S. Gov't, Non-P.H.S. England BMC systems biology BMC Syst Biol. 2009 Sep 15;3:92. PY - 2009 RN - fulltext fulltext_1208 SN - 1752-0509 (Electronic) 1752-0509 (Linking) SP - 92 ST - A systems biology framework for modeling metabolic enzyme inhibition of Mycobacterium tuberculosis T2 - BMC Syst Biol TI - A systems biology framework for modeling metabolic enzyme inhibition of Mycobacterium tuberculosis UR - http://www.biomedcentral.com/1752-0509/3/92http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2759933/pdf/1752-0509-3-92.pdf VL - 3 ID - 2568 ER - TY - JOUR AB - OBJECTIVE: People who live under fragile living conditions may stay overnight in Internet cafes in urban areas. An outbreak of tuberculosis (TB), the routes of which were possibly related to such a facility, has been reported. The purpose of this study was to use a mathematical model to quantify the public health risk of TB infection in such a facility. METHODS: The reproduction number for airborne infection in an enclosed space (R (A)) was estimated using a Wells-Riley model. First, we estimated R (A) for the TB infection based on the report of the TB outbreak in the Internet cafe. Second, TB infectious dose, number of days of exposure, and air-exchange rate in the facility were varied to estimate the effect of TB risk settings and environmental factors. RESULTS: We assumed that TB patients and 59 susceptible subjects stayed for 150 days in a room where the air-exchange rate was five per hour. Using the estimated median R (A) of 44.14, the TB infection rate was 74.6%. This result was similar to the epidemiological report that the TB infection rate among employees in the Internet cafe was 70%. The median R (A) increased linearly as the number of days of exposure increased. The slope of the change in median R (A) divided by the change in the number of days of exposure increased exponentially as air-exchange rate decreased; thus air ventilation in a facility may be essential to prevent TB infection. CONCLUSIONS: Appropriate air ventilation in facilities such as Internet cafes is needed as part of a TB-control program in metropolitan areas. AD - Basic Clinical Science and Public Health, Tokai University School of Medicine, Isehara, Kanagawa, 259-1193, Japan, furuya@is.icc.u-tokai.ac.jp AN - 19568853 AU - Furuya, H. AU - Nagamine, M. AU - Watanabe, T. DA - Mar DO - 10.1007/s12199-008-0062-9 [doi] DP - Nlm ET - 07/02 LA - eng N1 - Furuya, Hiroyuki Nagamine, Michiko Watanabe, Tetsu Japan Environmental health and preventive medicine Environ Health Prev Med. 2009 Mar;14(2):96-102. Epub 2008 Nov 20. PY - 2009 RN - fulltext fulltext_1208 SN - 1342-078X (Print) 1342-078X (Linking) SP - 96-102 ST - Use of a mathematical model to estimate tuberculosis transmission risk in an Internet cafe T2 - Environ Health Prev Med TI - Use of a mathematical model to estimate tuberculosis transmission risk in an Internet cafe UR - http://www.springerlink.com/content/y4p35w852t3768vl/ VL - 14 ID - 2569 ER - TY - JOUR AB - Policies regarding the use of the Bacille Calmette-Guerin (BCG) vaccine for tuberculosis vary greatly throughout the international community. In several countries, consideration of discontinuing universal vaccination programs is currently under way. The arguments against mass vaccination are that the effectiveness of BCG in preventing tuberculosis is uncertain and that BCG vaccination can interfere with the detection and treatment of latent tuberculosis. In this work, we pose a dynamical systems model for the population-level dynamics of tuberculosis in order to study the trade-off which occurs between vaccination and detection/treatment of latent tuberculosis. We assume that latent infection in vaccinated individuals is completely undetectable. For the case of a country with very low levels of tuberculosis, we establish analytic thresholds, via stability analysis and the basic reproductive number, which determine the optimal vaccination policy, given the effectiveness of the vaccine and the detection/treatment rate of latent tuberculosis. The results of this work suggest that it is unlikely that a country detects and treats latent tuberculosis at a high enough rate to justify the discontinuation of mass vaccination from this perspective. AD - Department of Mathematics, Purdue University, West Lafayette, IN 47907-2067, USA. gerberry@math.purdue.edu AN - 19733577 AU - Gerberry, D. J. DA - Dec 21 DO - S0022-5193(09)00409-3 [pii] 10.1016/j.jtbi.2009.08.029 [doi] DP - Nlm ET - 09/08 KW - BCG Vaccine Health Policy Humans Latent Tuberculosis/ diagnosis Mass Vaccination Mathematics Models, Theoretical Program Evaluation Tuberculosis/ prevention & control World Health LA - eng N1 - Gerberry, David J England Journal of theoretical biology J Theor Biol. 2009 Dec 21;261(4):548-60. Epub 2009 Sep 4. PY - 2009 RN - fulltext fulltext_1208 SN - 1095-8541 (Electronic) 0022-5193 (Linking) SP - 548-60 ST - Trade-off between BCG vaccination and the ability to detect and treat latent tuberculosis T2 - J Theor Biol TI - Trade-off between BCG vaccination and the ability to detect and treat latent tuberculosis UR - http://ac.els-cdn.com/S0022519309004093/1-s2.0-S0022519309004093-main.pdf?_tid=6bfa50d3f1b770ab01fcb7f24051a839&acdnat=1345012389_7a7e0c6069b2a2bc442ddf8e87662ebe VL - 261 ID - 2570 ER - TY - JOUR AB - Few tools exist to assess replication of chronic pathogens during infection. This has been a considerable barrier to understanding latent tuberculosis, and efforts to develop new therapies generally assume that the bacteria are very slowly replicating or nonreplicating during latency. To monitor Mycobacterium tuberculosis replication within hosts, we exploit an unstable plasmid that is lost at a steady, quantifiable rate from dividing cells in the absence of antibiotic selection. By applying a mathematical model, we calculate bacterial growth and death rates during infection of mice. We show that during chronic infection, the cumulative bacterial burden-enumerating total live, dead and removed organisms encountered by the mouse lung-is substantially higher than estimates from colony-forming units. Our data show that M. tuberculosis replicates throughout the course of chronic infection of mice and is restrained by the host immune system. This approach may also shed light on the replication dynamics of other chronic pathogens. AD - Division of Allergy and Infectious Diseases, University of Washington Medical Center, 1959 Northeast Pacific Street, Box 356523, Seattle, Washington 98195, USA. AN - 19182798 AU - Gill, W. P. AU - Harik, N. S. AU - Whiddon, M. R. AU - Liao, R. P. AU - Mittler, J. E. AU - Sherman, D. R. DA - Feb DO - nm.1915 [pii] 10.1038/nm.1915 [doi] DP - Nlm ET - 02/03 KW - Animals Base Sequence Colony Count, Microbial DNA Primers Mice Mice, Inbred C57BL Mycobacterium tuberculosis/ growth & development Plasmids Polymerase Chain Reaction Tuberculosis/ microbiology/physiopathology LA - eng N1 - Gill, Wendy P Harik, Nada S Whiddon, Molly R Liao, Reiling P Mittler, John E Sherman, David R R01 AI047744-05/AI/NIAID NIH HHS/United States Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't United States Nature medicine Nihms152087 Nat Med. 2009 Feb;15(2):211-4. Epub 2009 Feb 1. PY - 2009 RN - fulltext fulltext_1208 SN - 1546-170X (Electronic) 1078-8956 (Linking) SP - 211-4 ST - A replication clock for Mycobacterium tuberculosis T2 - Nat Med TI - A replication clock for Mycobacterium tuberculosis UR - http://www.nature.com.ez.lshtm.ac.uk/nm/journal/v15/n2/pdf/nm.1915.pdf VL - 15 ID - 2571 ER - TY - JOUR AB - Little information exists on the pulmonary pharmacology of antituberculosis drugs. We used population pharmacokinetic modeling and Monte Carlo simulation to describe and explore the pulmonary pharmacokinetics and pharmacodynamics of rifampin (RIF; rifampicin). A population pharmacokinetic model that adequately described the plasma, epithelial lining fluid (ELF), and alveolar cell (AC) concentrations of RIF in a population of 34 human volunteers was made by use of the nonparametric adaptive grid (NPAG) algorithm. The estimated concentrations correlated well with the measured concentrations, and there was little bias and good precision. The results obtained with the NPAG algorithm were then imported into Matlab software to perform a 10,000-subject Monte Carlo simulation. The ability of RIF to suppress the development of drug resistance and to induce a sufficient bactericidal effect against Mycobacterium tuberculosis was evaluated by calculating the proportion of subjects achieving specific target values for the maximum concentration of drug (C(max))/MIC ratio and the area under the concentration-time curve from time zero to 24 h (AUC(0-24))/MIC ratio, respectively. At the lowest MIC (0.01 mg/liter), after the administration of one 600-mg oral dose, the rates of target attainment for C(max)/MIC (> or =175) were 95% in ACs, 48.8% in plasma, and 35.9% in ELF. Under the same conditions, the target attainment results for the killing effect were 100% in plasma (AUC(0-24)/MIC > or = 271) but only 54.5% in ELF (AUC(0-24)/MIC > or = 665). The use of a 1,200-mg RIF dose was associated with better results for target attainment. The overall results suggest that the pulmonary concentrations obtained with the standard RIF dose are too low in most subjects. This work supports the need to evaluate higher doses of RIF for the treatment of patients with tuberculosis. AD - Hospices Civils de Lyon, Hopital Antoine Charial, Service Pharmaceutique, ADCAPT, 40 Avenue de la Table de Pierre, Francheville, France. sylvain.goutelle@chu-lyon.fr AN - 19380594 AU - Goutelle, S. AU - Bourguignon, L. AU - Maire, P. H. AU - Van Guilder, M. AU - Conte, J. E., Jr. AU - Jelliffe, R. W. DA - Jul DO - AAC.01520-08 [pii] 10.1128/AAC.01520-08 [doi] DP - Nlm ET - 04/22 KW - Algorithms Antitubercular Agents/ pharmacokinetics Computer Simulation Female Humans Lung/ metabolism Male Monte Carlo Method Prospective Studies Rifampin/ pharmacokinetics L1 - internal-pdf://2336466970/Goutelle-2009-Population modeling and Monte Ca.pdf LA - eng N1 - Goutelle, Sylvain Bourguignon, Laurent Maire, Pascal H Van Guilder, Michael Conte, John E Jr Jelliffe, Roger W EB005803/EB/NIBIB NIH HHS/United States Research Support, N.I.H., Extramural United States Antimicrobial agents and chemotherapy Antimicrob Agents Chemother. 2009 Jul;53(7):2974-81. Epub 2009 Apr 20. PY - 2009 RN - fulltext fulltext_1208 SN - 1098-6596 (Electronic) 0066-4804 (Linking) SP - 2974-81 ST - Population modeling and Monte Carlo simulation study of the pharmacokinetics and antituberculosis pharmacodynamics of rifampin in lungs T2 - Antimicrob Agents Chemother TI - Population modeling and Monte Carlo simulation study of the pharmacokinetics and antituberculosis pharmacodynamics of rifampin in lungs UR - http://aac.asm.org/content/53/7/2974.full.pdf https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2704682/pdf/1520-08.pdf VL - 53 ID - 2572 ER - TY - JOUR AB - For some diseases, the transmission of infection can cause spatial clustering of disease cases. This clustering has an impact on how one estimates the rate of the spread of the disease and on the design of control strategies. It is, however, difficult to assess such clustering, (local effects on transmission), using traditional statistical methods. A stochastic Markov-chain model that takes into account possible local or more dispersed global effects on the risk of contracting disease is introduced in the context of the transmission dynamics of tuberculosis. The model is used to analyse TB notifications collected in the Asembo and Gem Divisions of Nyanza Province in western Kenya by the Kenya Ministry of Health/National Leprosy and Tuberculosis Program and the Centers for Disease Control and Prevention. The model shows evidence of a pronounced local effect that is significantly greater than the global effect. We discuss a number of variations of the model which identify how this local effect depends on factors such as age and gender. Zoning/clustering of villages is used to identify the influence that zone size has on the model's ability to distinguish local and global effects. An important possible use of the model is in the design of a community randomised trial where geographical clusters of people are divided into two groups and the effectiveness of an intervention policy is assessed by applying it to one group but not the other. Here the model can be used to take the effect of case clustering into consideration in calculating the minimum difference in an outcome variable (e.g. disease prevalence) that can be detected with statistical significance. It thereby gauges the potential effectiveness of such a trial. Such a possible application is illustrated with the given time/spatial TB data set. AD - Warwick Business School, University of Warwick, University Road, Coventry, Warwickshire CV4 7AL, UK. kathryn.hoad@wbs.ac.uk AN - 19563744 AU - Hoad, K. A. AU - van't Hoog, A. H. AU - Rosen, D. AU - Marston, B. AU - Nyabiage, L. AU - Williams, B. G. AU - Dye, C. AU - Cheng, R. C. DA - Apr DO - S0025-5564(09)00021-2 [pii] 10.1016/j.mbs.2009.01.002 [doi] DP - Nlm ET - 07/01 KW - Age Factors Female Humans Kenya/epidemiology Male Markov Chains Models, Immunological Mycobacterium tuberculosis/ immunology Sex Factors Space-Time Clustering Tuberculosis/epidemiology/immunology/ transmission LA - eng N1 - Hoad, K A van't Hoog, A H Rosen, D Marston, B Nyabiage, L Williams, B G Dye, C Cheng, R C H Research Support, Non-U.S. Gov't United States Mathematical biosciences Math Biosci. 2009 Apr;218(2):98-104. Epub 2009 Jan 19. PY - 2009 RN - fulltext fulltext_1208 SN - 1879-3134 (Electronic) 0025-5564 (Linking) SP - 98-104 ST - Modelling local and global effects on the risk of contracting Tuberculosis using stochastic Markov-chain models T2 - Math Biosci TI - Modelling local and global effects on the risk of contracting Tuberculosis using stochastic Markov-chain models UR - http://ac.els-cdn.com/S0025556409000212/1-s2.0-S0025556409000212-main.pdf?_tid=77817aaa05622369ca0d29b39ce4a269&acdnat=1345012489_4856d1ca7ba758754fdd87eb5d14dd13 VL - 218 ID - 2573 ER - TY - JOUR AB - RATIONALE: Isoniazid given daily for 9 months is the standard treatment for latent tuberculosis infection (LTBI), but its effectiveness is limited by poor completion rates. Shorter course regimens and regimens using directly observed therapy result in improved adherence but have higher upfront costs. OBJECTIVES: To evaluate the costs and cost-effectiveness of regimens for the treatment of LTBI. METHODS: We used a computerized Markov model to estimate total societal costs and benefits associated with four regimens for the treatment of LTBI: self-administered isoniazid daily for 9 months, directly observed isoniazid twice-weekly for 9 months, directly observed isoniazid plus rifapentine once weekly for 3 months, and self-administered rifampin daily for 4 months. In the base-case analysis, subjects were assumed to have newly positive tuberculin skin tests after recent exposure to infectious tuberculosis. MEASUREMENTS AND MAIN RESULTS: We determined the costs of treatment, quality-adjusted life-years gained, and cases of active tuberculosis prevented. In the base-case analysis, rifampin dominated (less costly with increased benefits) all other regimens except isoniazid plus rifapentine, which was more effective at a cost $48,997 per quality-adjusted life year gained. Isoniazid plus rifapentine dominated all regimens at a relative risk of disease 5.2 times the baseline estimate, or with completion rates less than 34% for isoniazid or 37% for rifampin. Rifampin could be 17% less efficacious than self-administered isoniazid and still be cost-saving compared with this regimen. CONCLUSIONS: In our model, rifampin is cost-saving compared with the standard therapy of self-administered isoniazid. Isoniazid plus rifapentine is cost-saving for extremely high-risk patients and is cost-effective for lower-risk patients. AD - Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710, USA. AU - Holland, D. P. AU - Sanders, G. D. AU - Hamilton, C. D. AU - Stout, J. E. DO - 10.1164/rccm.200901-0153OC KW - Antitubercular Agents/administration & dosage/economics Cost-Benefit Analysis Directly Observed Therapy/economics Drug Administration Schedule Drug Therapy, Combination Humans Isoniazid/administration & dosage/economics Markov Chains Rifampin/administration & dosage/analogs & derivatives/economics Tuberculosis/drug therapy N1 - LR: 20100923; GR: 1-U54 AI057157/AI/NIAID NIH HHS/United States; JID: 9421642; 0 (Antitubercular Agents); 13292-46-1 (Rifampin); 54-85-3 (Isoniazid); 61379-65-5 (rifapentine); OID: NLM: PMC2689913; 2009/03/19 [aheadofprint]; ppublish PY - 2009 RN - fulltext fulltext_1208 SN - 1535-4970; 1073-449X SP - 1055-1060 ST - Costs and cost-effectiveness of four treatment regimens for latent tuberculosis infection T2 - American journal of respiratory and critical care medicine TI - Costs and cost-effectiveness of four treatment regimens for latent tuberculosis infection VL - 179 Y2 - Jun 1 ID - 2574 ER - TY - THES AB - In this thesis, a mathematical model describing the interaction between HIV and TB in the presence of TB superinfection is presented. The model takes into account two strains of Mycobacterium tuberculosis (MTB), where one strain is drug-sensitive and the other is resistant to at least one of the first-line anti-tuberculosis drugs. The impact of TB superinfection on the incidence and prevalence of TB in HIV-negative and HIVTB coinfected individuals is evaluated. Various control measures such as condom use, antiretroviral therapy, isoniazid preventive therapy and increased TB detection are studied using this model. Numerical results show that TB superinfection increases the prevalence and incidence of TB and its impact is more in HIV-negative than HIV-TB coinfected individuals. The results also show that TB superinfection promotes strain coexistence and increases the associated HIV mortality. Increased condom use was found to have a high positive impact towards the control of the two epidemics. Antiretroviral therapy decreases the TB notification rate and its impact on HIV prevalence increases with the coverage and efficacy. Isoniazid preventive therapy has a clear effect on the TB prevalence. Finally, increased TB detection was found to have a less impact on the TB incidence in HIV-TB coinfected individuals AU - Kajunguri, D. L1 - internal-pdf://3487199912/kajunguri_modelling_2009.pdf PB - University of Stellenbosch PY - 2009 ST - MODELLING THE IMPACT OF TB SUPERINFECTION ON THE DYNAMICS OF HIV-TB COINFECTION TI - MODELLING THE IMPACT OF TB SUPERINFECTION ON THE DYNAMICS OF HIV-TB COINFECTION VL - MSc ID - 4936 ER - TY - JOUR AB - The aim of this paper is to describe the development and use of a computer simulation model that can be used as a Decision Support System (DSS) to tackle the critical public health issues of HIV and HIV-related tuberculosis in the Russian Federation. This country has recently witnessed an explosion of HIV infections and a worrying spread of the Multi-Drug Resistant form of Tuberculosis (MDRTB). The conclusions drawn are that a high population coverage with Highly Active Anti-Retroviral Treatment (HAART) (75% or higher), allied with high MDRTB cure rates, reduces cumulative deaths by 60%, with limited impact below this level. This research offers a simulation model that can be applied as a DSS by public health officials to inform policy making. By doing so, ways of controlling the spread of HIV and MDRTB and reduce mortality from these serious public health threats is provided. AD - Business School, University of Hertfordshire, Hatfield, Herts, AL 10 9AB, UK. M.R.Lebcir@Herts.ac.uk AN - 19505866 AU - Lebcir, R. M. AU - Choudrie, J. AU - Atun, R. A. AU - Coker, R. J. DO - G86453764772W185 [pii] DP - Nlm ET - 06/10 KW - AIDS-Related Opportunistic Infections/ drug therapy/mortality/transmission Antiretroviral Therapy, Highly Active/ utilization Antitubercular Agents/administration & dosage/ therapeutic use Computer Simulation Decision Support Systems, Clinical/ organization & administration Directly Observed Therapy Humans Models, Biological Russia/epidemiology Tuberculosis, Multidrug-Resistant/drug therapy/mortality/transmission Tuberculosis, Pulmonary/ drug therapy/mortality/transmission LA - eng N1 - Lebcir, Reda M Choudrie, Jyoti Atun, Rifat A Coker, Richard J Switzerland International journal of electronic healthcare Int J Electron Healthc. 2009;5(1):14-32. PY - 2009 RN - fulltext fulltext_1208 SN - 1741-8453 (Print) 1741-8453 (Linking) SP - 14-32 ST - Using a decision support systems computer simulation model to examine HIV and tuberculosis: the Russian Federation T2 - Int J Electron Healthc TI - Using a decision support systems computer simulation model to examine HIV and tuberculosis: the Russian Federation UR - https://www.inderscienceonline.com/doi/abs/10.1504/IJEH.2009.02627?url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&rfr_dat=cr_pub%3Dpubmed VL - 5 ID - 2576 ER - TY - JOUR AB - A tuberculosis (TB) model with two latent periods, short-term latent period (E(1)) and long-term latent period (E(2)), and fast and slow progressions is analyzed. The stability of the unique endemic equilibrium of the model is proved. It turns out that the disease-free equilibrium is globally asymptotically stable if the basic reproduction number R(0) <= 1, and the endemic equilibrium is globally asymptotically stable if R(0) > 1. AD - Liu, LJ Xi An Jiao Tong Univ, Dept Math, Xian 710049, Peoples R China Xi An Jiao Tong Univ, Dept Math, Xian 710049, Peoples R China Xi An Jiao Tong Univ, Dept Math, Xian 710049, Peoples R China Mem Univ Newfoundland, Dept Math & Stat, St John, NF A1C 5S7, Canada AN - WOS:000279191500009 AU - Liu, L. J. DA - Sep DO - 10.1142/S1793524509000480 IS - 3 J2 - Int J Biomath KW - tb model endemic equilibrium globally stability lyapunov function transmission epidemiology infection LA - English N1 - 616el Times Cited:3 Cited References Count:14 PY - 2009 SN - 1793-5245 SP - 357-362 ST - Global Stability in a Tuberculosis Model Incorporating Two Latent Periods T2 - International Journal of Biomathematics TI - Global Stability in a Tuberculosis Model Incorporating Two Latent Periods UR - ://WOS:000279191500009 VL - 2 ID - 2198 ER - TY - JOUR AB - We provide the complete classification of all global analytic first integrals of the simplified multistrain/two-stream model for tuberculosis and dengue fever that can be written as (x) over dot = x(beta(1) - b - gamma(1) - beta(1)x - (beta(1) - nu)y), (y) over dot = y(beta(2) - b - gamma(2) - (beta(2) + nu)x - beta(2)y), with beta(1), beta(2), b, gamma(1), gamma(2), nu is an element of R. AD - [Llibre, Jaume] Univ Autonoma Barcelona, Dept Matemat, E-08193 Barcelona, Spain. [Valls, Claudia] Inst Super Tecn, Dept Matemat, P-1049001 Lisbon, Portugal. Llibre, J (reprint author), Univ Autonoma Barcelona, Dept Matemat, E-08193 Barcelona, Spain. jllibre@mat.uab.cat; cvalls@math.ist.utl.pt AN - WOS:000274916800009 AU - Llibre, J. AU - Valls, C. DA - Dec DO - 10.1142/s1402925109000510 IS - 4 J2 - J. Nonlinear Math. Phys. KW - Analytic first integral multistrain/two-stream model tuberculosis dengue fever transmission Mathematics Physics LA - English M3 - Article N1 - ISI Document Delivery No.: 560QI Times Cited: 4 Cited Reference Count: 9 Llibre, Jaume Valls, Claudia Valls, Claudia/H-5040-2015; Llibre, Jaume/F-4225-2016 Llibre, Jaume/0000-0002-9511-5999; Valls, Claudia/0000-0001-8279-1229 MCYT/FEDER [MTM 2008-03437]; CICYT [2009SGR 410]; FCT through CAMGDS, Lisbon The first author has been supported by the grants MCYT/FEDER MTM 2008-03437 and CICYT grant number 2009SGR 410. The second author has been partially supported by FCT through CAMGDS, Lisbon. 4 0 2 Atlantis press Paris PY - 2009 SN - 1402-9251 SP - 505-516 ST - GLOBAL ANALYTIC FIRST INTEGRALS FOR THE SIMPLIFIED MULTISTRAIN/TWO-STREAM MODEL FOR TUBERCULOSIS AND DENGUE FEVER T2 - Journal of Nonlinear Mathematical Physics TI - GLOBAL ANALYTIC FIRST INTEGRALS FOR THE SIMPLIFIED MULTISTRAIN/TWO-STREAM MODEL FOR TUBERCULOSIS AND DENGUE FEVER UR - ://WOS:000274916800009 VL - 16 ID - 5883 ER - TY - JOUR AB - The emergence of antibiotic resistance in Mycobacterium tuberculosis has raised the concern that pathogen strains that are virtually untreatable may become widespread. The acquisition of resistance to antibiotics results in a longer duration of infection in a host, but this resistance may come at a cost through a decreased transmission rate. This raises the question of whether the overall fitness of drug-resistant strains is higher than that of sensitive strains--essential information for predicting the spread of the disease. Here, we directly estimate the transmission cost of drug resistance, the rate at which resistance evolves, and the relative fitness of resistant strains. These estimates are made by using explicit models of the transmission and evolution of sensitive and resistant strains of M. tuberculosis, using approximate Bayesian computation, and molecular epidemiology data from Cuba, Estonia, and Venezuela. We find that the transmission cost of drug resistance relative to sensitivity can be as low as 10%, that resistance evolves at rates of approximately 0.0025-0.02 per case per year, and that the overall fitness of resistant strains is comparable with that of sensitive strains. Furthermore, the contribution of transmission to the spread of drug resistance is very high compared with acquired resistance due to treatment failure (up to 99%). Estimating such parameters directly from in vivo data will be critical to understanding and responding to antibiotic resistance. For instance, projections using our estimates suggest that the prevalence of tuberculosis may decline with successful treatment, but the proportion of cases associated with resistance is likely to increase. AD - School of Biotechnology and Biomolecular Sciences, University of New South Wales, Kensington, NSW 2052, Australia. AN - 19706556 AU - Luciani, F. AU - Sisson, S. A. AU - Jiang, H. AU - Francis, A. R. AU - Tanaka, M. M. DA - Aug 25 DO - 0902437106 [pii] 10.1073/pnas.0902437106 ET - 08/27 KW - Algorithms Antitubercular Agents/*therapeutic use Bayes Theorem Cuba/epidemiology Drug Resistance, Multiple, Bacterial Estonia/epidemiology Humans Models, Theoretical Mycobacterium tuberculosis/*drug effects Tuberculosis, Multidrug-Resistant/*drug therapy/epidemiology/transmission Venezuela/epidemiology L1 - internal-pdf://0465276404/Luciani-2009-The epidemiological fitness cost.pdf LA - eng N1 - Luciani, Fabio Sisson, Scott A Jiang, Honglin Francis, Andrew R Tanaka, Mark M Research Support, Non-U.S. Gov't United States Proceedings of the National Academy of Sciences of the United States of America Proc Natl Acad Sci U S A. 2009 Aug 25;106(34):14711-5. Epub 2009 Aug 13. PY - 2009 RN - fulltext fulltext_1208 SN - 1091-6490 (Electronic) SP - 14711-14715 ST - The epidemiological fitness cost of drug resistance in Mycobacterium tuberculosis T2 - Proc Natl Acad Sci U S A TI - The epidemiological fitness cost of drug resistance in Mycobacterium tuberculosis UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=19706556http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2732896/pdf/zpq14711.pdf https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2732896/pdf/zpq14711.pdf VL - 106 ID - 2577 ER - TY - JOUR AB - Natural infection with Mycobacterium tuberculosis, as well as cross-immune reactions with the constituent of standard vaccines, attenuated M. bovis, and other species of mycobacteria confer partial immunity to subsequent M. tuberculosis infection, It has been shown in the past that the immune response to mycobacteria found naturally in the environment reduces the benefit of vaccination as assessed by means of vaccine efficacy. In this paper we show that efficacy is a poor measure of the potential success of new anti-tuberculous vaccines due to its inability to account for the relative weight of reinfection in disease dynamics. We advocate instead the use of vaccine effectiveness when evaluating the impact of new control methods against infections that confer partial immunity. Through the study of a simple model that incorporates cross-reactive responses to environmental mycobacteria (EM) and reinfection, we show how the particulars of the relation between EM abundance and vaccine effectiveness depend on the degree of protection conferred respectively by natural infection, vaccination and EM. The relative importance of reinfection as a transmission mechanism comes Lip as the most important source of variability in vaccine effectiveness. Our results suggest that control efforts should be placed in reducing the importance of reinfection through diminishing transmission rates. Vaccines that overcome preexisting immunity to other mycobacteria will still have varying degrees of success depending on the underlying rate of TB transmission. (C) 2009 Elsevier Inc. All rights reserved. AD - Univ Nacl Autonoma Mexico, Inst Fis, Mexico City 04510, DF, Mexico Gulbenkian Inst Sci, P-2781901 Oeiras, Portugal Univ Lisbon, Ctr Matemat & Aplicacoes Fundamentais, P-1649003 Lisbon, Portugal AN - WOS:000265736600006 AU - Mantilla-Beniers, N. B. AU - Gomes, M. G. M. DA - Mar-May DO - 10.1016/j.tpb.2009.01.006 IS - 2-3 J2 - Theor Popul Biol KW - epidemiology disease ecology tuberculosis reinfection vaccine efficacy effectiveness intervention effectiveness bcg environmental mycobacteria cross-immunity bovis bcg vaccination exogenous reinfection environmental mycobacteria recurrent tuberculosis northern malawi heterologous immunity infectious-diseases prior exposure efficacy epidemiology LA - English N1 - 440yw Times Cited:2 Cited References Count:39 PY - 2009 SN - 0040-5809 SP - 142-152 ST - Mycobacterial ecology as a modulator of tuberculosis vaccine success T2 - Theoretical Population Biology TI - Mycobacterial ecology as a modulator of tuberculosis vaccine success UR - ://WOS:000265736600006 VL - 75 ID - 4853 ER - TY - JOUR AB - We formulate and analyze a deterministic mathematical model which incorporates some basic epidemiological features of the co-dynamics of malaria and tuberculosis. Two sub-models, namely: malaria-only and TB-only sub-models are considered first of all. Sufficient conditions for the local stability of the steady states are presented. Global stability of the disease-free steady state does not hold because the two sub-models exhibit backward bifurcation. The dynamics of the dual malaria-TB only sub-model is also analyzed. It has different dynamics to that of malaria-only and TB-only sub-models: the dual malaria-TB only model has no positive endemic equilibrium whenever R(MT)(d) < 1, - its disease free equilibrium is globally asymptotically stable whenever the reproduction number for dual malaria-TB co-infection only R(MT)(d) < 1 - it does not exhibit the phenomenon of backward bifurcation. Graphical representations of this phenomenon is shown, while numerical simulations of the full model are carried out in order to determine whether the two diseases will co-exist whenever their partial reproductive numbers exceed unity. Finally, we perform sensitivity analysis on the key parameters that drive the disease dynamics in order to determine their relative importance to disease transmission. AD - Dar es Salaam Inst Technol, Dar Es Salaam, Tanzania Univ Dar Es Salaam, Dept Math, Dar Es Salaam, Tanzania AN - WOS:000271091400008 AU - Mtisi, E. AU - Rwezaura, H. AU - Tchuenche, J. M. DA - Nov DO - 10.3934/dcdsb.2009.12.827 IS - 4 J2 - Discrete Cont Dyn-B KW - malaria-tb model co-dynamics basic reproduction number equilibrium stability sensitivity model hiv transmission coinfection bifurcation strategies vaccines diseases burden LA - English N1 - 510ma Times Cited:16 Cited References Count:40 PY - 2009 SN - 1531-3492 SP - 827-864 ST - A Mathematical Analysis of Malaria and Tuberculosis Co-Dynamics T2 - Discrete and Continuous Dynamical Systems-Series B TI - A Mathematical Analysis of Malaria and Tuberculosis Co-Dynamics UR - ://WOS:000271091400008 VL - 12 ID - 4854 ER - TY - JOUR AB - In this paper, the cumulative effect of ecological factors in the habitat on the spread of tuberculosis (TB) in human population is modeled and analyzed. The total human population is divided into two classes, susceptibles and infectives. It is assumed that TB is not only spread by direct contacts with infectives in the population but also indirectly by bacteria which are emitted by infectives in the habitat. It is assumed further that bacteria survive due to conducive ecological factors such as flower pots, plants, grasses, human clothes, etc. in the habitat. The cumulative density of ecological factors in the habitat is assumed to be governed by a population density dependent logistic model. The analysis of the model shows that as parameters governing the conducive ecological factors in the habitat increase, the spread of TB increases. The same result is also found with the increase in the parameter governing the survival and accumulation of bacteria in the habitat. It is further found that due to immigration of the population TB becomes more endemic. A numerical study of the model is also carried out to support the analytical results. AD - [Naresh, Ram; Pandey, Surabhi] Harcourt Butler Technol Inst, Dept Math, Kanpur 208002, Uttar Pradesh, India. [Shukla, J. B.] Ctr Modelling Environm & Dev, Kanpur 208017, Uttar Pradesh, India. [Shukla, J. B.] LNM Indian Inst Technol Jaipur, Jaipur 303012, Rajasthan, India. Naresh, R (reprint author), Harcourt Butler Technol Inst, Dept Math, Kanpur 208002, Uttar Pradesh, India. ramntripathi@yahoo.com; psurabhi_81@yahoo.co.in; jbs@iitk.ac.in AN - WOS:000279191500008 AU - Naresh, R. AU - Pandey, S. AU - Shukla, J. B. DA - Sep DO - 10.1142/s1793524509000728 IS - 3 J2 - Int. J. Biomath. KW - Mycobacterium tuberculosis ecological density bacterial population stability simulation Mathematical & Computational Biology LA - English M3 - Article N1 - ISI Document Delivery No.: 616EL Times Cited: 3 Cited Reference Count: 23 Naresh, Ram Pandey, Surabhi Shukla, J. B. 3 0 4 World scientific publ co pte ltd Singapore PY - 2009 SN - 1793-5245 SP - 339-355 ST - MODELING THE CUMULATIVE EFFECT OF ECOLOGICAL FACTORS IN THE HABITAT ON THE SPREAD OF TUBERCULOSIS T2 - International Journal of Biomathematics TI - MODELING THE CUMULATIVE EFFECT OF ECOLOGICAL FACTORS IN THE HABITAT ON THE SPREAD OF TUBERCULOSIS UR - ://WOS:000279191500008 http://www.worldscientific.com/doi/abs/10.1142/S1793524509000728 VL - 2 ID - 5903 ER - TY - JOUR AB - A nonlinear mathematical model is proposed to study the effect of tuberculosis on the spread of HIV infection in a logistically growing human population. The host population is divided into four sub classes of susceptibles, TB infectives, HIV infectives (with or without TB) and that of AIDS patients. The model exhibits four equilibria namely, a disease free, HIV free, TB free and an endemic equilibrium. The model has been studied qualitatively using stability theory of nonlinear differential equations and computer simulation. We have found a threshold parameter R 0 which is if less than one, the disease free equilibrium is locally asymptotically stable otherwise for R 0 > 1 , at least one of the infections will be present in the population. It is shown that the positive endemic equilibrium is always locally stable but it may become globally stable under certain conditions showing that the disease becomes endemic. It is found that as the number of TB infectives decreases due to recovery, the number of HIV infectives also decreases and endemic equilibrium tends to TB free equilibrium. It is also observed that number of AIDS individuals decreases if TB is not associated with HIV infection. A numerical study of the model is also performed to investigate the influence of certain key parameters on the spread of the disease. AU - Naresh, Ram AU - Sharma, Dileep AU - Tripathi, Agraj DO - 10.1016/j.mcm.2009.05.033 KW - HIV/AIDS epidemic PY - 2009 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 0895-7177 SP - 1154-1166 ST - Modelling the effect of tuberculosis on the spread of HIV infection in a population with density-dependent birth and death rate T2 - Mathematical and Computer Modelling TI - Modelling the effect of tuberculosis on the spread of HIV infection in a population with density-dependent birth and death rate UR - http://www.sciencedirect.com/science/article/pii/S0895717709002131http://ac.els-cdn.com/S0895717709002131/1-s2.0-S0895717709002131-main.pdf?_tid=91543dc8067263b6b14d2bc42dec2019&acdnat=1345012911_4304f0798d5c14dfd87464c2a818a108 VL - 50 ID - 2578 ER - TY - JOUR AB - Epidemics such as tuberculosis (TB), can be represented by a finite number of states and transition rules that govern the spread of the disease in each discrete time step. This paper Uses a graph theoretic approach to investigate TB interactions in a community where infectives are categorized. A threshold value, alpha = 1 - 1/n, for 'reasonable' infectives is proposed. The results show that ail epidemic will not ensue as long as the threshold is Surpassed. Simulations presented show that unreasonable infectives can amplify the epidemic. (C) 2009 Elsevier B.V. All rights reserved. AD - [Nyabadza, Farai] Univ Stellenbosch, S African Ctr Epidemiol Modelling & Anal, ZA-7600 Stellenbosch, South Africa. [Mukwembi, Simon; Rodrigues, Bernardo Gabriel] Univ KwaZulu Natal, Sch Math Sci, Durban, South Africa. Nyabadza, F (reprint author), Univ Stellenbosch, S African Ctr Epidemiol Modelling & Anal, 19 Jonkershoek Rd, ZA-7600 Stellenbosch, South Africa. nyabadzaf@sun.ac.za AN - WOS:000265016600004 AU - Nyabadza, F. AU - Mukwembi, S. AU - Rodrigues, B. G. DA - May DO - 10.1016/j.physa.2009.01.039 IS - 10 J2 - Physica A KW - Tuberculosis Graph Contacts Transition States heterogeneous populations transmission dynamics complex networks epidemic reinfection tb Physics LA - English M3 - Article N1 - ISI Document Delivery No.: 430VC Times Cited: 2 Cited Reference Count: 17 Nyabadza, Farai Mukwembi, Simon Rodrigues, Bernardo Gabriel Rodrigues, Bernardo/0000-0002-1349-0219; Nyabadza, Farai/0000-0003-3468-5581 Sacema The first author acknowledges, with thanks, the support of SACEMA (DST/NRF Centre of Excellence in Epidemiological Modelling and Analysis) and the University of KwaZulu-Natal for the research visit that they fully funded during which this work was done. The second and third authors acknowledge, with gratitude, the financial support of the University of KwaZulu-Natal. 2 0 Elsevier science bv Amsterdam PY - 2009 SN - 0378-4371 SP - 1995-2000 ST - A tuberculosis model: The case of 'reasonable' and 'unreasonable' infectives T2 - Physica a-Statistical Mechanics and Its Applications TI - A tuberculosis model: The case of 'reasonable' and 'unreasonable' infectives UR - ://WOS:000265016600004 VL - 388 ID - 5922 ER - TY - JOUR AD - [Pareek, Manish; White, Peter J.; Garnett, Geoffrey P.] Univ London Imperial Coll Sci Technol & Med, MRC Ctr Outbreak Anal & Modelling, Dept Infect Dis Epidemiol, London, England. [White, Peter J.] Ctr Infect, Hlth Protect Agcy, Modelling & Econ Unit, London, England. [Pareek, Manish; Lalvani, Ajit] Univ London Imperial Coll Sci Technol & Med, TB Res Unit, Dept Resp Med, London, England. AN - WOS:000273714700037 AU - Pareek, M. AU - White, P. J. AU - Lalvani, A. AU - Garnett, G. P. DA - Dec IS - 6 J2 - J. Infect. KW - Infectious Diseases LA - English M3 - Meeting Abstract N1 - ISI Document Delivery No.: 545EG Times Cited: 0 Cited Reference Count: 0 Pareek, Manish White, Peter J. Lalvani, Ajit Garnett, Geoffrey P. 0 1 2 W b saunders co ltd London PY - 2009 SN - 0163-4453 SP - S442-S442 ST - MODELLING THE HEALTH IMPACT AND COST-EFFECTIVENESS OF SCREENING NEW ENTRANTS TO THE UK FOR LATENT TUBERCULOSIS INFECTION T2 - Journal of Infection TI - MODELLING THE HEALTH IMPACT AND COST-EFFECTIVENESS OF SCREENING NEW ENTRANTS TO THE UK FOR LATENT TUBERCULOSIS INFECTION UR - ://WOS:000273714700037 VL - 59 ID - 5882 ER - TY - JOUR AB - A stochastic individual-based model of the spread of tuberculosis is considered. The model is based on a system of stochastic recurrent equations with integer-valued variables and discrete time. Individuals differ by the duration of different states of their disease (noninfectious, infectious, in remission) and by values of the parameters describing their life time distribution. Monte Carlo methods are used for numerical experiments based on the model. The dynamics of the number of individuals depending on the variation of the parameters of the model is studied. AD - [Pertsev, N. V.; Leonenko, V. N.] Russian Acad Sci, Siberian Branch, Sobolev Inst Math, Omsk 644099, Russia. Pertsev, NV (reprint author), Russian Acad Sci, Siberian Branch, Sobolev Inst Math, Omsk 644099, Russia. AN - WOS:000269370000004 AU - Pertsev, N. V. AU - Leonenko, V. N. DO - 10.1515/rjnamm.2009.021 IS - 4 J2 - Russ. J. Numer. Anal. Math. Model KW - Engineering Mathematics LA - English M3 - Article N1 - ISI Document Delivery No.: 488SL Times Cited: 3 Cited Reference Count: 11 Pertsev, N. V. Leonenko, V. N. Leonenko, Vasiliy/E-8752-2013; Pertsev, Nikolay/F-8086-2013 Pertsev, Nikolay/0000-0002-5674-7096 Russian Foundation for Basic Research [09-01-00098-a] The work was supported by the Russian Foundation for Basic Research (09-01-00098-a). 3 1 4 Walter de gruyter & co Berlin PY - 2009 SN - 0927-6467 SP - 341-360 ST - Stochastic individual-based model of spread of tuberculosis T2 - Russian Journal of Numerical Analysis and Mathematical Modelling TI - Stochastic individual-based model of spread of tuberculosis UR - ://WOS:000269370000004 VL - 24 ID - 5953 ER - TY - JOUR AB - Heterogeneity in susceptibility and infectivity is inherent to infectious disease transmission in nature. Here we are concerned with the formulation of mathematical models that capture the essence of heterogeneity while keeping a simple structure suitable of analytical treatment. We explore the consequences of host heterogeneity in the susceptibility to infection for epidemiological models for which immunity conferred by infection is partially protective, known as susceptible-infected-recovered-infected (SIRI) models. We analyze the impact of heterogeneity on disease prevalence and contrast the susceptibility profiles of the subpopulations at risk for primary infection and reinfection. We present a systematic study in the case of two frailty groups. We predict that the average rate of reinfection may be higher than the average rate of primary infection, which may seem paradoxical given that primary infection induces life-long partial protection. Infection generates a selection mechanism whereby fit individuals remain in S and frail individuals are transferred to R. If this effect is strong enough we have a scenario where, on average, the rate of reinfection is higher than the rate of primary infection even though each individual has a risk reduction following primary infection. This mechanism may explain high rates of tuberculosis reinfection recently reported. Finally, the enhanced benefits of vaccination strategies that target the high-risk groups are quantified. AD - Instituto Gulbenkian de Ciencia, Apartado 14, 2781-901 Oeiras, Portugal. pcpr@igc.gulbenkian.pt AN - 19306886 AU - Rodrigues, P. AU - Margheri, A. AU - Rebelo, C. AU - Gomes, M. G. DA - Jul 21 DO - S0022-5193(09)00126-X [pii] 10.1016/j.jtbi.2009.03.013 [doi] DP - Nlm ET - 03/25 KW - Communicable Diseases/epidemiology/ immunology/transmission Disease Susceptibility Endemic Diseases Humans Immunization Programs/organization & administration Immunologic Memory Models, Biological Recurrence Risk Assessment/methods Tuberculosis/epidemiology/immunology/prevention & control/transmission LA - eng N1 - Rodrigues, Paula Margheri, Alessandro Rebelo, Carlota Gomes, M Gabriela M Research Support, Non-U.S. Gov't England Journal of theoretical biology J Theor Biol. 2009 Jul 21;259(2):280-90. Epub 2009 Mar 21. PY - 2009 RN - fulltext fulltext_1208 SN - 1095-8541 (Electronic) 0022-5193 (Linking) SP - 280-90 ST - Heterogeneity in susceptibility to infection can explain high reinfection rates T2 - J Theor Biol TI - Heterogeneity in susceptibility to infection can explain high reinfection rates UR - http://ac.els-cdn.com/S002251930900126X/1-s2.0-S002251930900126X-main.pdf?_tid=0e76250e4b0924442f25d4e7f94d036f&acdnat=1345013156_bb0915944646b87f81a0b0a2e026cb6c VL - 259 ID - 2579 ER - TY - JOUR AB - Tuberculosis (TB) is the leading cause of death among individuals infected with the human immunodeficiency virus (HIV). The study of the joint dynamics of HIV and TB present formidable mathematical challenges due to the fact that the models of transmission are quite distinct. Furthermore, although there is overlap in the populations at risk of HIV and TB infections, the magnitude of the proportion of individuals at risk for both diseases is not known. Here, we consider a highly simplified deterministic model that incorporates the joint dynamics of TB and HIV, a model that is quite hard to analyze. We compute independent reproductive numbers for TB (R1) and HIV (R2) and the overall reproductive number for the system, R=max{R1, R2}. The focus is naturally (given the highly simplified nature of the framework) on the qualitative analysis of this model. We find that if R < 1 then the disease-free equilibrium is locally asymptotically stable. The TB-only equilibrium ET is locally asymptotically stable if R1 < 1 and R2 < 1. However, the symmetric condition, R1 < 1 and R2 > 1, does not necessarily guarantee the stability of the HIV-only equilibrium EH, and it is possible that TB can coexist with HIV when R2 > 1. In other words, in the case when R1 < 1 and R2 > 1 (or when R1 > 1 and R2 > 1), we are able to find a stable HIV/TB coexistence equilibrium. Moreover, we show that the prevalence level of TB increases with R2 > 1 under certain conditions. Through simulations, we find that i) the increased progression rate from latent to active TB in co-infected individuals may play a significant role in the rising prevalence of TB; and ii) the increased progression rates from HIV to AIDS have not only increased the prevalence level of HIV while decreasing TB prevalence, but also generated damped oscillations in the system. AD - Department of Mathematics and Statistics, Box 41042, Texas Tech University, Lubbock, TX 79409, USA. lih-ing.roeger@ttu.edu AN - 19835430 AU - Roeger, L. I. AU - Feng, Z. AU - Castillo-Chavez, C. DA - Oct DO - 10.3934/mbe.2009.6.815. DP - Nlm ET - 10/20 KW - Comorbidity HIV Infections/ complications/epidemiology Humans Mathematical Concepts Models, Biological Risk Factors Time Factors Tuberculosis, Pulmonary/ complications/epidemiology LA - eng PY - 2009 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1547-1063 (Print) 1547-1063 (Linking) SP - 815-37 ST - Modeling TB and HIV co-infections T2 - Math Biosci Eng TI - Modeling TB and HIV co-infections VL - 6 ID - 2580 ER - TY - JOUR AB - OBJECTIVE: Kenya is heralded as an example of declining HIV in Africa, while its tuberculosis (TB) numbers continue rising. We conducted a comparative investigation of TB-HIV co-dynamics in Africa to determine the likelihood of reported trends. METHODS AND RESULTS: Our mathematical modeling analysis exposes the notable incongruence of reported trends in Kenya because TB-HIV co-dynamics, tightly knit worldwide and most dramatically in sub-Saharan Africa, suggest that declining HIV trends should trigger reductions in TB trends. Moreover, a continental-scale analysis of TB-HIV trends places Kenya as an outlier in eastern and southern Africa, and shows TB outpacing HIV in western central Africa. We further investigate which TB processes across HIV stages have greater potential to reduce TB incidence via a sensitivity analysis. CONCLUSIONS: There are two parsimonious explanations: an unaccounted improvement in TB case detection has occurred, or HIV is not declining as reported. The TB-HIV mismatch could be compounded by surveillance biases due to spatial heterogeneity in disease dynamics. Results highlight the need to re-evaluate trends of both diseases in Kenya, and identify the most critical epidemiological factors at play. Substantial demographic changes have occurred in Kenya, including rapid urbanization accompanied by poor living conditions, which could disproportionately increase TB incidence. Other possible contributors include immune reconstitution due to the recent delivery of antiretrovirals, and an increased presence of the virulent Beijing/W TB genotype. Results support the importance of integrating information from closely interacting epidemics, because this approach provides critical insights unobtainable when components of generalized epidemics are considered individually. AD - Department of Environmental Science, Policy and Management, University of California, 137 Mulford Hall, Berkeley, CA 94720-3112, USA. msanchez@nature.berkeley.edu AN - 21352748 AU - Sanchez, M. S. AU - Lloyd-Smith, J. O. AU - Williams, B. G. AU - Porco, T. C. AU - Ryan, S. J. AU - Borgdorff, M. W. AU - Mansoer, J. AU - Dye, C. AU - Getz, W. M. DA - Mar DO - S1755-4365(08)00003-0 [pii] 10.1016/j.epidem.2008.08.001 [doi] DP - Nlm ET - 03/01 KW - Anti-Retroviral Agents/therapeutic use HIV Infections/drug therapy/ epidemiology Humans Kenya/epidemiology Models, Biological Prevalence Sentinel Surveillance Tuberculosis/diagnosis/ epidemiology/prevention & control LA - eng N1 - Sanchez, Maria S Lloyd-Smith, James O Williams, Brian G Porco, Travis C Ryan, Sadie J Borgdorff, Martien W Mansoer, John Dye, Christopher Getz, Wayne M Comparative Study Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't Netherlands Epidemics Epidemics. 2009 Mar;1(1):14-20. Epub 2008 Nov 6. PY - 2009 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1878-0067 (Electronic) 1878-0067 (Linking) SP - 14-20 ST - Incongruent HIV and tuberculosis co-dynamics in Kenya: interacting epidemics monitor each other T2 - Epidemics TI - Incongruent HIV and tuberculosis co-dynamics in Kenya: interacting epidemics monitor each other UR - http://ac.els-cdn.com/S1755436508000030/1-s2.0-S1755436508000030-main.pdf?_tid=d70a98b54da4304818c4ac65a058feac&acdnat=1345013202_c90577b411728ebebe90e509ba017b8c VL - 1 ID - 2581 ER - TY - JOUR AB - The long-term persistence of Mycobacterium tuberculosis in communities with high tuberculosis prevalence is a serious problem aggravated by the presence of drug-resistant tuberculosis strains. Drug resistance in an individual patient is often discovered only after a long delay, particularly if the diagnosis is based on current culture-based drug sensitivity testing methods. During such delays, the patient may transmit tuberculosis to his or her contacts. Rapid diagnosis of drug resistance would be expected to reduce this transmission and hence to decrease the prevalence of drug-resistant strains. To investigate this quantitatively, a mathematical model was constructed, assuming a homogeneous population structure typical of communities in South Africa where tuberculosis incidence is high. Computer simulations performed with this model showed that current control strategies will not halt the spread of multidrug-resistant tuberculosis in such communities. The simulations showed that the rapid diagnosis of drug resistance can be expected to reduce the incidence of drug-resistant cases provided the additional measure of screening within the community is implemented. AD - Faculty of Health Sciences, MRC Center for Molecular and Cellular Biology, DST/NRF Centre of Excellence for Biomedical Tuberculosis Research, Stellenbosch University, Tygerberg, South Africa. pieter@edserve.co.za AN - 19297604 AU - Uys, P. W. AU - Warren, R. AU - van Helden, P. D. AU - Murray, M. AU - Victor, T. C. DA - May DO - JCM.02289-08 [pii] 10.1128/JCM.02289-08 [doi] DP - Nlm ET - 03/20 KW - Computer Simulation Drug Resistance, Multiple, Bacterial Humans Microbial Sensitivity Tests Models, Theoretical Mycobacterium tuberculosis/ drug effects/genetics/ isolation & purification South Africa Time Factors Tuberculosis, Multidrug-Resistant/ diagnosis/ microbiology/transmission L1 - internal-pdf://1495523986/Uys-2009-Potential of rapid diagnosis for cont.pdf LA - eng N1 - Uys, Pieter W Warren, Robin van Helden, Paul D Murray, Megan Victor, Thomas C Research Support, Non-U.S. Gov't United States Journal of clinical microbiology J Clin Microbiol. 2009 May;47(5):1484-90. Epub 2009 Mar 18. PY - 2009 RN - fulltext fulltext_1208 SN - 1098-660X (Electronic) 0095-1137 (Linking) SP - 1484-90 ST - Potential of rapid diagnosis for controlling drug-susceptible and drug-resistant tuberculosis in communities where Mycobacterium tuberculosis infections are highly prevalent T2 - J Clin Microbiol TI - Potential of rapid diagnosis for controlling drug-susceptible and drug-resistant tuberculosis in communities where Mycobacterium tuberculosis infections are highly prevalent UR - http://jcm.asm.org/content/47/5/1484.full.pdf https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2681859/pdf/2289-08.pdf VL - 47 ID - 2583 ER - TY - JOUR AB - BACKGROUND: The incidence of tuberculosis (TB) in The Netherlands has been declining for many years. For the purpose of planning future TB-control activities we estimated the number of TB patients in The Netherlands up to 2030. METHODS: Statistical modelling for 5-year age groups up to 2030 distinguishing among Dutch TB patients infected by a Dutch source (survival model), non-Dutch patients (projection of the proportion of culture-positive patients among first generation immigrants) and Dutch patients infected by a non-Dutch source (fixed relation with the number of non-Dutch patients). RESULTS: The number of TB patients is expected to decline to 877 in 2030. After 2010 declines may slow due to an increase in non-Dutch TB patients. This increase cancels out the decrease of Dutch TB patients infected by a Dutch source. In 2030, 85% of all TB patients are expected to be non-Dutch. In the four largest counties and the rest of The Netherlands, this will be 89 and 76%, respectively. CONCLUSION: The decrease in TB incidence observed over many years may stall from 2010 onwards because of an estimated increase in non-Dutch TB patients. Given their disproportionate burden, future TB-control activities should prioritize the health of first-generation immigrants. Enhanced TB control in the countries of origin and new diagnostic tests to identify those at high risk of developing active TB could help in reducing further the TB incidence in the Netherlands. Future TB-control efforts must be organized in a flexible way to be able to incorporate changing epidemiological situations. AD - KNCV Tuberculosis Foundation, 2514 JD Den Haag, The Hague, The Netherlands. vanlethf@kncvtbc.nl AN - 19357241 AU - van Leth, F. AU - Kalisvaart, N. A. AU - Erkens, C. G. AU - Borgdoff, M. W. DA - Aug DO - ckp042 [pii] 10.1093/eurpub/ckp042 [doi] DP - Nlm ET - 04/10 KW - Adolescent Adult Aged Female Forecasting Humans Life Tables Male Middle Aged Netherlands/epidemiology Tuberculosis/ epidemiology/ethnology Young Adult LA - eng N1 - van Leth, Frank Kalisvaart, Nico A Erkens, Connie G M Borgdoff, Martien W England European journal of public health Eur J Public Health. 2009 Aug;19(4):424-7. Epub 2009 Apr 8. PY - 2009 RN - fulltext fulltext_1208 SN - 1464-360X (Electronic) 1101-1262 (Linking) SP - 424-7 ST - Projection of the number of patients with tuberculosis in the Netherlands in 2030 T2 - Eur J Public Health TI - Projection of the number of patients with tuberculosis in the Netherlands in 2030 UR - http://eurpub.oxfordjournals.org/content/19/4/424.full.pdf VL - 19 ID - 2584 ER - TY - BILL AB - We consider a four-compartment tuberculosis model including exogenous reinfection. We derive sufficient conditions, in terms of the parameters of the system, which guarantee the occurrence of backward bifurcation. We also discuss the global stability of the endemic state by using a generalization of the Poincaré-Bendixson criterion. An application is given for the case of Internally Displaced People's Camps in North Uganda. The study suggests how important it is to provide qualitative indications on the threshold value of the population density in the area occupied by the camps, in order to possibly eradicate the disease. AD - a Department of Mathematics and Applications , University of Naples Federico II , via Cintia , I-80126 , Naples , Italy. AN - 22881205 DA - Nov 1 LB - p31787 M1 - 6 PY - 2010 RN - fulltext fulltext_1208 SP - 571-93 ST - Analysis of a tuberculosis model with a case study in Uganda T2 - J Biol Dyn TI - Analysis of a tuberculosis model with a case study in Uganda UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=22881205 VL - 4 ID - 2590 ER - TY - JOUR AB - In this paper we consider the fractional order model with two immune effectors interacting with two strain antigen. The systems may explain the recurrence of some diseases e.g. tuberculosis (TB). The stability of equilibrium points are studied. Numerical solutions of this model are given. Using integer order system the system oscillates. Using fractional order system the system converges to a stable internal equilibrium. Ulam-Hyers stability of the system has been studied. AD - Mathematics Department, Damietta Faculty of Science, Mansoura University, 34517, New Damietta, Egypt. halaelsaka@yahoo.com. AN - 21106113 AU - Ahmed el, S. M. AU - El-Saka, H. A. DO - 1753-4631-4-6 [pii] 10.1186/1753-4631-4-6 [doi] DP - Nlm ET - 11/26 LA - eng N1 - Ahmed, El-Sayed M El-Saka, Hala A United States Nonlinear biomedical physics Nonlinear Biomed Phys. 2010 Nov 25;4:6. PY - 2010 RN - fulltext fulltext_1208 SN - 1753-4631 (Electronic) 1753-4631 (Linking) SP - 6 ST - On modeling two immune effectors two strain antigen interaction T2 - Nonlinear Biomed Phys TI - On modeling two immune effectors two strain antigen interaction UR - http://www.nonlinearbiomedphys.com/content/pdf/1753-4631-4-6.pdf VL - 4 ID - 2585 ER - TY - JOUR AB - Smoking has long being associated with tuberculosis. We present a tuberculosis dynamics model taking into account the fact that some people in the population are smoking in order to assess the effects of smoking on tuberculosis transmission. The epidemic thresholds known as the reproduction numbers and equilibria for the model are determined and stabilities analyzed. Qualitative analysis of the model including positivity and persistence of solutions are presented. The model is numerically analyzed to assess the effects of smoking on the transmission dynamics of tuberculosis. Numerical simulations of the model show that smoking enhances tuberculosis transmission, progression to active disease and in a population of smokers, tuberculosis cannot be controlled even when treatment success is assumed to be as high as 88%. Further, analysis of the reproduction numbers indicates that the number of active tuberculosis cases increases as the number of smokers increase. AD - Department of Applied Mathematics, Modelling Biomedical Systems Research Group, National University of Science and Technology, Ascot, Bulawayo, Zimbabwe. cpbhunu@gmail.com AN - 20725798 AU - Bhunu, C. P. AU - Mushayabasa, S. AU - Tchuenche, J. M. DA - Jun DO - 10.1007/s11538-010-9568-6 [doi] DP - Nlm ET - 08/21 KW - Antitubercular Agents/therapeutic use Basic Reproduction Number Computer Simulation Humans Models, Immunological Mycobacterium tuberculosis/ immunology Smoking/adverse effects/ immunology Tuberculosis/drug therapy/ immunology/ transmission LA - eng N1 - Bhunu, C P Mushayabasa, S Tchuenche, J M United States Bulletin of mathematical biology Bull Math Biol. 2011 Jun;73(6):1333-57. Epub 2010 Aug 20. PY - 2010 RN - fulltext fulltext_1208 SN - 1522-9602 (Electronic) 0092-8240 (Linking) SP - 1333-57 ST - A theoretical assessment of the effects of smoking on the transmission dynamics of tuberculosis T2 - Bull Math Biol TI - A theoretical assessment of the effects of smoking on the transmission dynamics of tuberculosis UR - http://www.springerlink.com/content/4n410216p3555249/ VL - 73 ID - 2611 ER - TY - JOUR AB - Background: Prior infection with one strain TB has been linked with diminished likelihood of re-infection by a new strain. This paper attempts to determine the role of declining prevalence of drug-susceptible TB in enabling future epidemics of MDR-TB. Methods: A computer simulation of MDR-TB epidemics was developed using an agent-based model platform programmed in NetLogo (See http://mdr.tbtools.org/). Eighty-one scenarios were created, varying levels of treatment quality, diagnostic accuracy, microbial fitness cost, and the degree of immunogenicity elicited by drug-susceptible TB. Outcome measures were the number of independent MDR-TB cases per trial and the proportion of trials resulting in MDR-TB epidemics for a 500 year period after drug therapy for TB is introduced. Results: MDR-TB epidemics propagated more extensively after TB prevalence had fallen. At a case detection rate of 75%, improving therapeutic compliance from 50% to 75% can reduce the probability of an epidemic from 45% to 15%. Paradoxically, improving the case-detection rate from 50% to 75% when compliance with DOT is constant at 75% increases the probability of MDR-TB epidemics from 3% to 45%. Conclusions: The ability of MDR-TB to spread depends on the prevalence of drug-susceptible TB. Immunologic protection conferred by exposure to drug-susceptible TB can be a crucial factor that prevents MDR-TB epidemics when TB treatment is poor. Any single population that successfully reduces its burden of drug-susceptible TB will have reduced herd immunity to externally or internally introduced strains of MDR-TB and can experience heightened vulnerability to an epidemic. Since countries with good TB control may be more vulnerable, their self interest dictates greater promotion of case detection and DOTS implementation in countries with poor control to control their risk of MDR-TB. AD - Stanford Univ, Sch Humanities & Sci, Stanford, CA 94305 USA Johns Hopkins Sch Med, Dept Med, Div Infect Dis, Baltimore, MD USA Johns Hopkins Bloomberg Sch Publ Hlth, Baltimore, MD USA AN - WOS:000282053100016 AU - Bishai, J. D. AU - Bishai, W. R. AU - Bishai, D. M. DA - Sep 22 DO - ARTN e12843 10.1371/journal.pone.0012843 IS - 9 J2 - Plos One KW - resistant mycobacterium-tuberculosis exogenous reinfection united-states transmission emergence dynamics russia model patterns fitness L1 - internal-pdf://1603501073/Bishai-2010-Heightened Vulnerability to MDR-TB.pdf LA - English N1 - 653ac Times Cited:7 Cited References Count:37 PY - 2010 SN - 1932-6203 ST - Heightened Vulnerability to MDR-TB Epidemics after Controlling Drug-Susceptible TB T2 - Plos One TI - Heightened Vulnerability to MDR-TB Epidemics after Controlling Drug-Susceptible TB UR - ://WOS:000282053100016 http://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0012843&type=printable VL - 5 ID - 4856 ER - TY - JOUR AB - SETTING: Bleach sedimentation is a method used to increase the diagnostic yield of sputum microscopy for countries with a high prevalence of human immunodeficiency virus (HIV) infection and limited resources. OBJECTIVES: To compare the relative cost-effectiveness of different microscopy approaches in diagnosing tuberculosis (TB) in Kenya. METHODS: An analytical decision tree model including cost and effectiveness measures of 10 combinations of direct (D) and overnight bleach (B) sedimentation microscopy was constructed. Data were drawn from the evaluation of the bleach sedimentation method on two specimens (first on the spot [1] and second morning [2]) from 644 TB suspects in a peripheral health clinic. Incremental cost per smear-positive detected case was measured. Costs included human resources and materials using a micro-costing evaluation. RESULTS: All bleach-based microscopy approaches detected significantly more cases (between 23.3% for B1 and 25.9% for B1+B2) than the conventional D1+D2 approach (21.0%). Cost per tested case ranged between respectively euro 2.7 and euro 4.5 for B1 and B1+D2+B2. B1 and B1+B2 were the most cost-effective approaches. D1+B2 and D1+B1 were good alternatives to avoid using approaches exclusively based on bleach sedimentation microscopy. CONCLUSIONS: Among several effective microscopy approaches used, including sodium hypochlorite sedimentation, only some resulted in a limited increase in the laboratory workload and would be most suitable for programmatic implementation. AD - Epicentre, Paris, France. maryline.bonnet@geneva.msf.org AN - 20392349 AU - Bonnet, M. AU - Tajahmady, A. AU - Hepple, P. AU - Ramsay, A. AU - Githui, W. AU - Gagdnidze, L. AU - Guerin, P. J. AU - Varaine, F. DA - May DP - Nlm ET - 04/16 J2 - The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease KW - Centrifugation Cost-Benefit Analysis Decision Trees Humans Kenya/epidemiology Microscopy/economics/ methods Sodium Hypochlorite/ chemistry Sputum/ microbiology Time Factors Tuberculosis, Pulmonary/ diagnosis/epidemiology LA - eng N1 - Bonnet, M Tajahmady, A Hepple, P Ramsay, A Githui, W Gagdnidze, L Guerin, P J Varaine, F Research Support, Non-U.S. Gov't France Int J Tuberc Lung Dis. 2010 May;14(5):571-7. PY - 2010 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1815-7920 (Electronic) 1027-3719 (Linking) SP - 571-7 ST - Added value of bleach sedimentation microscopy for diagnosis of tuberculosis: a cost-effectiveness study T2 - Int J Tuberc Lung Dis TI - Added value of bleach sedimentation microscopy for diagnosis of tuberculosis: a cost-effectiveness study VL - 14 ID - 2587 ER - TY - JOUR AB - This paper deals with the problem of optimal control for the transmission dynamics of tuberculosis (TB). A tuberculosis model which incorporates the essential biological and epidemiological features of the disease such as exogenous reinfection and chemoprophylaxis of latently infected individuals, and treatment of the infectious is developed and rigorously analyzed. Based on this continuous model, the tuberculosis control is formulated and solved as an optimal control theory problem, indicating how a control term on the chemoprophylaxis should be introduced in the population to reduce the number of individuals with active TB. The feedback control law has been proved to be capable of reducing the number of individuals with active TB. An advantage is that the proposed scheme accounts for the energy wasted by the controller and the closed-loop performance on tracking. Numerical results show the performance of the optimization strategy. AD - Univ Douala, Fac Sci, Dept Math & Comp Sci, Lab Appl Math, Douala, Cameroon UPMC UMMISCO, IRD, UMI 209, Bondy, France Projet MASAIE INRIA Grand Est, Paris, France AN - WOS:000281012800012 AU - Bowong, S. DA - Sep DO - 10.1007/s11071-010-9683-9 IS - 4 J2 - Nonlinear Dynam KW - epidemiological models tuberculosis optimal control riccati equation exogenous reinfection backward bifurcation model systems hiv synchronization vaccination evolution diseases relapse LA - English N1 - 639yj Times Cited:18 Cited References Count:59 PY - 2010 SN - 0924-090x SP - 729-748 ST - Optimal control of the transmission dynamics of tuberculosis T2 - Nonlinear Dynamics TI - Optimal control of the transmission dynamics of tuberculosis UR - ://WOS:000281012800012 VL - 61 ID - 4857 ER - TY - JOUR AB - Tuberculosis (TB) is the leading cause of death among individuals infected with the hepatitis B virus (HBV). The study of the joint dynamics of HBV and TB present formidable mathematical challenges due to the fact that the models of transmission are quite distinct. We formulate and analyze a deterministic mathematical model which incorporates of the co-dynamics of hepatitis B and tuberculosis. Two sub-models, namely: HBV-only and TB-only sub-models are considered first of all. Unlike the HBV-only sub-model, which has a globally-asymptotically stable disease-free equilibrium whenever the associated reproduction number is less than unity, the TB-only sub-model undergoes the phenomenon of backward bifurcation, where a stable disease-free equilibrium co-exists with a stable endemic equilibrium, for a certain range of the associated reproduction number less than unity. Thus, for TB, the classical requirement of having the associated reproduction number to be less than unity, although necessary, is not sufficient for its elimination. It is also shown, that the full HBV-TB co-infection model undergoes a backward bifurcation phenomenon. Through simulations, we mainly find that i) the two diseases will co-exist whenever their partial reproductive numbers exceed unity; (ii) the increased progression rate due to exogenous reinfection from latent to active TB in co-infected individuals may play a significant role in the rising prevalence of TB; and (iii) the increased progression rates from acute stage to chronic stage of HBV infection have increased the prevalence levels of HBV and TB prevalences. AD - Univ Douala, Lab Appl Math, Dept Math & Comp Sci, Fac Sci, Douala, Cameroon Postdam Inst Climate Impact Res PIK, D-14412 Potsdam, Germany Humboldt Univ, Dept Phys, D-12489 Berlin, Germany UPMC, UMI 209, IRD, UMMISCO,Projet MASAIE INRIA Grand Est, Bondy, France AN - WOS:000286884800010 AU - Bowong, S. AU - Kurths, J. DO - 10.1051/mmnp/20105610 IS - 6 J2 - Math Model Nat Pheno KW - nonlinear dynamical systems epidemiological models tuberculosis hepatitis b stability highly endemic areas virus-infection transmission dynamics mathematical-analysis backward bifurcations exogenous reinfection disease burden hiv vaccination prevalence LA - English N1 - 2 715la Times Cited:2 Cited References Count:64 PY - 2010 SN - 0973-5348 SP - 196-242 ST - Modelling Tuberculosis and Hepatitis B Co-infections T2 - Mathematical Modelling of Natural Phenomena TI - Modelling Tuberculosis and Hepatitis B Co-infections UR - ://WOS:000286884800010 VL - 5 ID - 4859 ER - TY - JOUR AB - We propose a method based on synchronization to identify the parameters and to estimate the underlying variables for an epidemic model from real data. We suggest an adaptive synchronization method based on observer approach with an effective guidance parameter to update rule design only from real data. In order, to validate the identifiability and estimation results, numerical simulations of a tuberculosis (TB) model using real data of the region of Center in Cameroon are performed to estimate the parameters and variables. This study shows that some tools of synchronization of nonlinear systems can help to deal with the parameter and state estimation problem in the field of epidemiology. We exploit the close link between mathematical modelling, structural identifiability analysis, synchronization, and parameter estimation to obtain biological insights into the system modelled. (C) 2010 Elsevier B.V. All rights reserved. AD - Univ Douala, Fac Sci, Dept Math & Comp Sci, Lab Appl Math, Douala, Cameroon Postdam Inst Climate Impact Res PIK, D-14412 Potsdam, Germany Humboldt Univ, Dept Phys, D-12489 Berlin, Germany AN - WOS:000283344200003 AU - Bowong, S. AU - Kurths, J. DA - Oct 4 DO - 10.1016/j.physleta.2010.09.008 IS - 44 J2 - Phys Lett A KW - epidemiological models parameter identification adaptive synchronization tuberculosis systems dynamics LA - English N1 - 669jr Times Cited:11 Cited References Count:30 PY - 2010 SN - 0375-9601 SP - 4496-4505 ST - Parameter estimation based synchronization for an epidemic model with application to tuberculosis in Cameroon T2 - Physics Letters A TI - Parameter estimation based synchronization for an epidemic model with application to tuberculosis in Cameroon UR - ://WOS:000283344200003 VL - 374 ID - 4860 ER - TY - JOUR AB - This paper deals with the global analysis of a dynamical model for the spread of tuberculosis with a general contact rate The model exhibits the traditional threshold behavior We prove that when the basic reproduction ratio is less than unity, then the disease-free equilibrium is globally asymptotically stable and when the basic reproduction ratio is great than unity, a unique endemic equilibrium exists and is globally asymptotically stable under certain conditions. The stability of equilibria is derived through the use of Lyapunov stability theory and LaSalle's invariant set theorem. Numerical simulations are provided to illustrate the theoretical results (C) 2010 Elsevier B V All rights reserved AD - Univ Douala, Fac Sci, Dept Math & Comp Sci, Lab Appl Math, Douala, Cameroon Postdam Inst Climate Impact Res PIK, D-14412 Potsdam, Germany Univ Yaounde, Dept Math & Phys, Natl Adv Sch Engn, Yaounde, Cameroon IRD UPMC UMMISCO, UMI 209, Project MASAIE INRIA Grand Est, Bondy, France LIRIMA, Project GRIMCAPE, Yaounde, Cameroon AN - WOS:000278723500044 AU - Bowong, S. AU - Tewa, J. J. DA - Nov DO - 10.1016/j.cnsns.2010.01.007 IS - 11 J2 - Commun Nonlinear Sci KW - dynamical systems epidemiological models general contact rate tuberculosis global stability lyapunov functions heterogeneous populations epidemiologic models lyapunov functions stability analysis seir strategies systems sir LA - English N1 - 610hw Times Cited:12 Cited References Count:46 PY - 2010 SN - 1007-5704 SP - 3621-3631 ST - Global analysis of a dynamical model for transmission of tuberculosis with a general contact rate T2 - Communications in Nonlinear Science and Numerical Simulation TI - Global analysis of a dynamical model for transmission of tuberculosis with a general contact rate UR - ://WOS:000278723500044 VL - 15 ID - 4861 ER - TY - JOUR AB - BACKGROUND: Mathematical models of tuberculosis (TB) transmission have been used to characterize disease dynamics, investigate the potential effects of public health interventions, and prioritize control measures. While previous work has addressed the mathematical description of TB natural history, the impact of demography on the behaviour of TB models has not been assessed. METHODS: A simple model of TB transmission, with alternative assumptions about survivorship, is used to explore the effect of age structure on the prevalence of infection, disease, basic reproductive ratio and the projected impact of control interventions. We focus our analytic arguments on the differences between constant and exponentially distributed lifespans and use an individual-based model to investigate the range of behaviour arising from realistic distributions of survivorship. RESULTS: The choice of age structure and natural (non-disease related) mortality strongly affects steady-state dynamics, parameter estimation and predictions about the effectiveness of control interventions. Since most individuals infected with TB develop an asymptomatic latent infection and never progress to active disease, we find that assuming a constant mortality rate results in a larger reproductive ratio and an overestimation of the effort required for disease control in comparison to using more realistic age-specific mortality rates. CONCLUSIONS: Demographic modelling assumptions should be considered in the interpretation of models of chronic infectious diseases such as TB. For simple models, we find that assuming constant lifetimes, rather than exponential lifetimes, produces dynamics more representative of models with realistic age structure. AD - Department of Epidemiology, Harvard School of Public Health, Brigham and Women's Hospital, Boston, Massachusetts, United States of America. ebrooks@hsph.harvard.edu AN - 20062531 AU - Brooks-Pollock, E. AU - Cohen, T. AU - Murray, M. DO - 10.1371/journal.pone.0008479 [doi] DP - Nlm ET - 01/12 KW - Humans Models, Theoretical Prevalence Tuberculosis/mortality/ transmission LA - eng N1 - Brooks-Pollock, Ellen Cohen, Ted Murray, Megan DP2 OD006663-01/OD/NIH HHS/United States U19 AI076217/AI/NIAID NIH HHS/United States Research Support, N.I.H., Extramural United States PloS one PLoS One. 2010 Jan 7;5(1):e8479. PY - 2010 RN - fulltext fulltext_1208 SN - 1932-6203 (Electronic) 1932-6203 (Linking) SP - e8479 ST - The impact of realistic age structure in simple models of tuberculosis transmission T2 - PLoS One TI - The impact of realistic age structure in simple models of tuberculosis transmission UR - http://www.plosone.org/article/fetchObjectAttachment.action?uri=info%3Adoi%2F10.1371%2Fjournal.pone.0008479&representation=PDF VL - 5 ID - 2588 ER - TY - JOUR AB - BACKGROUND: Mycobacterium tuberculosis is a particularly aggressive microorganism and the host's defense is based on the induction of cellular immunity, in which the creation of a granulomatous structure has an important role. METHODOLOGY: We present here a new 2D cellular automata model based on the concept of a multifunctional process that includes key factors such as the chemokine attraction of the cells; the role of innate immunity triggered by natural killers; the presence of neutrophils; apoptosis and necrosis of infected macrophages; the removal of dead cells by macrophages, which induces the production of foamy macrophages (FMs); the life cycle of the bacilli as a determinant for the evolution of infected macrophages; and the immune response. RESULTS: The results obtained after the inclusion of two degrees of tolerance to the inflammatory response triggered by the infection shows that the model can cover a wide spectrum, ranging from highly-tolerant (i.e. mice) to poorly-tolerant hosts (i.e. mini-pigs or humans). CONCLUSIONS: This model suggest that stopping bacillary growth at the onset of the infection might be difficult and the important role played by FMs in bacillary drainage in poorly-tolerant hosts together with apoptosis and innate lymphocytes. It also shows the poor ability of the cellular immunity to control the infection, provides a clear protective character to the granuloma, due its ability to attract a sufficient number of cells, and explains why an already infected host can be constantly reinfected. AD - Departamento de Matematica Aplicada, Facultad de Matematicas, Universidad Complutense de Madrid, Madrid, Spain. AN - 20886087 AU - Bru, A. AU - Cardona, P. J. DO - 10.1371/journal.pone.0012985 [doi] DP - Nlm ET - 10/05 KW - Animals Chemokines/immunology Granuloma/immunology/microbiology Host-Pathogen Interactions Humans Macrophages/immunology/microbiology Mice Models, Biological Models, Theoretical Mycobacterium tuberculosis/ chemistry/ growth & development/immunology/physiology Swine Swine, Miniature Tuberculosis/ immunology/ microbiology LA - eng N1 - Bru, Antonio Cardona, Pere-Joan Research Support, Non-U.S. Gov't United States PloS one PLoS One. 2010 Sep 23;5(9):e12985. PY - 2010 RN - fulltext fulltext_1208 SN - 1932-6203 (Electronic) 1932-6203 (Linking) SP - e12985 ST - Mathematical modeling of tuberculosis bacillary counts and cellular populations in the organs of infected mice T2 - PLoS One TI - Mathematical modeling of tuberculosis bacillary counts and cellular populations in the organs of infected mice UR - http://www.plosone.org/article/fetchObjectAttachment.action?uri=info%3Adoi%2F10.1371%2Fjournal.pone.0012985&representation=PDF VL - 5 ID - 2589 ER - TY - CHAP AB - A discrete tuberculosis model with different infectious compartments is formulated and studied. The basic reproduction number, of the model is defined. The global stability of the disease-free equilibrium is proved if R-0 < 1. The existence of endemic equilibrium and the persistence of TB is established if R-0 > 1. The main attention is paid on the influence of the infectivity proportion on the case number. The numerical simulations show that the infection cases increase as p increase. AD - [Cao, Hui; Zhou, Yicang] Xi An Jiao Tong Univ, Dept Math, Xian 710049, Peoples R China. Cao, H (reprint author), Xi An Jiao Tong Univ, Dept Math, Xian 710049, Peoples R China. caohui0103@163.com; zhouyc@mail.xjtu.edu.cn AN - WOS:000397260202044 AU - Cao, H. AU - Zhou, Y. C. AU - Ieee CY - New York KW - Discrete epidemic model Smear-positive Smear-negative Tuberculosis epidemic models time sis LA - English N1 - ISI Document Delivery No.: BH0ZM Times Cited: 0 Cited Reference Count: 11 Cao, Hui Zhou, Yicang Icbbe 2010 Proceedings Paper 4th International Conference on Bioinformatics and Biomedical Engineering (iCBBE) Jun 18-20, 2010 Chengdu, PEOPLES R CHINA IEEE Engn Med & Biol Soc, Sichuan Univ, Wuhan Univ Nsfc [10971163] The work was supported by NSFC # 10971163 345 e 47th st, new york, ny 10017 usa 2151-7614 PB - Ieee PY - 2010 SN - 978-1-4244-4713-8 ST - A Discrete Tuberculosis Model with Two Different Infectious Compartments T2 - 2010 4th International Conference on Bioinformatics and Biomedical Engineering T3 - International Conference on Bioinformatics and Biomedical Engineering TI - A Discrete Tuberculosis Model with Two Different Infectious Compartments UR - ://WOS:000397260202044 ID - 5850 ER - TY - JOUR AB - Endogenous infection and exogenous reinfection are two mechanisms responsible for the reactivation or regeneration of active tuberculosis (TB) in individuals who have experienced prior active TB infections. We provide a brief review of a classical reinfection model, introduce a more general model, and include some new results. We conclude with a snapshot on the use of reinfection models in the study of the evolution of TB. AD - Arizona State Univ, Computat Modeling Sci Ctr, POB 871904, Tempe, AZ 85287 USA Arizona State Univ, Sch human Evolut & Social Changes, Tempe, AZ 85287 USA Arizona State Univ, Sch Math & Stat, Tempe, AZ 85287 USA Santa Fe Inst, Santa Fe, NM 87501 USA Univ Nacl Salla, Inst Invest Energias Convencionales, RA-4400 Salla, Argentina AN - WOS:000290496200021 AU - Castillo-Chavez, C. AU - Wang, X. AU - Aparicio, J. P. AU - Feng, Z. DO - Doi 10.1142/9789814304900_0021 KW - brief epidemiologic history intrinsic transmission dynamics exogenous reinfection disease epidemics arcana models USA strategies age LA - English N1 - Buw21 Times Cited:0 Cited References Count:44 PY - 2010 SP - 304-+ ST - On the Dynamics of Reinfection: The Case of Tuberculosis T2 - Biomat 2009 TI - On the Dynamics of Reinfection: The Case of Tuberculosis UR - ://WOS:000290496200021 http://www.worldscientific.com/doi/abs/10.1142/9789814304900_0021 ID - 4862 ER - TY - JOUR AB - Prediction of metabolic changes that result from genetic or environmental perturbations has several important applications, including diagnosing metabolic disorders and discovering novel drug targets. A cardinal challenge in obtaining accurate predictions is the integration of transcriptional regulatory networks with the corresponding metabolic network. We propose a method called probabilistic regulation of metabolism (PROM) that achieves this synthesis and enables straightforward, automated, and quantitative integration of high-throughput data into constraint-based modeling, making it an ideal tool for constructing genome-scale regulatory-metabolic network models for less-studied organisms. PROM introduces probabilities to represent gene states and gene-transcription factor interactions. By using PROM, we constructed an integrated regulatory-metabolic network for the model organism, Escherichia coli, and demonstrated that our method based on automated inference is more accurate and comprehensive than the current state of the art, which is based on manual curation of literature. After validating the approach, we used PROM to build a genome-scale integrated metabolic-regulatory model for Mycobacterium tuberculosis, a critically important human pathogen. This study incorporated data from more than 1,300 microarrays, 2,000 transcription factor-target interactions regulating 3,300 metabolic reactions, and 1,905 KO phenotypes for E. coli and M. tuberculosis. PROM identified KO phenotypes with accuracies as high as 95%, and predicted growth rates quantitatively with correlation of 0.95. Importantly, PROM represents the successful integration of a top-down reconstructed, statistically inferred regulatory network with a bottom-up reconstructed, biochemically detailed metabolic network, bridging two important classes of systems biology models that are rarely combined quantitatively. AD - Center for Biophysics and Computational Biology, Institute for Genomic Biology, Department of Chemical and Biomolecular Engineering, University of Illinois, Urbana, IL 61801, USA. AN - 20876091 AU - Chandrasekaran, S. AU - Price, N. D. DA - Oct 12 DO - 1005139107 [pii] 10.1073/pnas.1005139107 [doi] DP - Nlm ET - 09/30 KW - Algorithms Computational Biology/ methods Escherichia coli/ genetics Gene Regulatory Networks/ genetics Genome, Bacterial/genetics Metabolic Networks and Pathways/ genetics Models, Genetic Mycobacterium tuberculosis/ genetics Systems Biology/ methods LA - eng N1 - Chandrasekaran, Sriram Price, Nathan D R00 CA126184-04/CA/NCI NIH HHS/United States Evaluation Studies Research Support, N.I.H., Extramural Research Support, U.S. Gov't, Non-P.H.S. United States Proceedings of the National Academy of Sciences of the United States of America Proc Natl Acad Sci U S A. 2010 Oct 12;107(41):17845-50. Epub 2010 Sep 27. PY - 2010 RN - fulltext fulltext_1208 SN - 1091-6490 (Electronic) 0027-8424 (Linking) SP - 17845-50 ST - Probabilistic integrative modeling of genome-scale metabolic and regulatory networks in Escherichia coli and Mycobacterium tuberculosis T2 - Proc Natl Acad Sci U S A TI - Probabilistic integrative modeling of genome-scale metabolic and regulatory networks in Escherichia coli and Mycobacterium tuberculosis UR - http://www.pnas.org/content/107/41/17845.full.pdf VL - 107 ID - 2591 ER - TY - JOUR AB - The objective of this article is to characterize the risk of infection from airborne Mycobacterium tuberculosis bacilli exposure in commercial passenger trains based on a risk-based probabilistic transmission modeling. We investigated the tuberculosis (TB) infection risks among commercial passengers by inhaled aerosol M. tuberculosis bacilli and quantify the patterns of TB transmission in Taiwan High Speed Rail (THSR). A deterministic Wells-Riley mathematical model was used to account for the probability of infection risk from M. tuberculosis bacilli by linking the cough-generated aerosol M. tuberculosis bacilli concentration and particle size distribution. We found that (i) the quantum generation rate of TB was estimated with a lognormal distribution of geometric mean (GM) of 54.29 and geometric standard deviation (GSD) of 3.05 quantum/h at particle size euro75 000/YLG was when the prevalence of LTBI around TB was low (<5%) and TST specificity high (>90%). CONCLUSIONS: In France, for the diagnosis of LTBI after close contact with TB, the TST is more expensive and less effective than QFT. Although it is more expensive, QFT is more effective and cost-effective than TST+QFT under a wide range of realistic test performance scenarios. AD - Institut National de la Sante et de la Recherche Medicale (INSERM) U795, Faculte de Medecine, Lille, France. sylvie.burban@yahoo.fr AN - 20202306 AU - Deuffic-Burban, S. AU - Atsou, K. AU - Viget, N. AU - Melliez, H. AU - Bouvet, E. AU - Yazdanpanah, Y. DA - Apr DP - Nlm ET - 03/06 KW - Adult BCG Vaccine Computer Simulation Contact Tracing Cost-Benefit Analysis Decision Support Techniques Decision Trees France Health Care Costs Humans Interferon-gamma/ analysis Latent Tuberculosis/ diagnosis/ economics/immunology Life Expectancy Mass Screening/ economics/methods Predictive Value of Tests Reagent Kits, Diagnostic/ economics Tuberculin Test/ economics LA - eng N1 - Deuffic-Burban, S Atsou, K Viget, N Melliez, H Bouvet, E Yazdanpanah, Y Comparative Study Evaluation Studies Research Support, Non-U.S. Gov't France The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease Int J Tuberc Lung Dis. 2010 Apr;14(4):471-81. PY - 2010 RN - fulltext fulltext_1208 SN - 1815-7920 (Electronic) 1027-3719 (Linking) SP - 471-81 ST - Cost-effectiveness of QuantiFERON-TB test vs. tuberculin skin test in the diagnosis of latent tuberculosis infection T2 - Int J Tuberc Lung Dis TI - Cost-effectiveness of QuantiFERON-TB test vs. tuberculin skin test in the diagnosis of latent tuberculosis infection VL - 14 ID - 2595 ER - TY - JOUR AB - Tuberculosis (TB) granulomas are organized collections of immune cells comprised of macrophages, lymphocytes and other cells that form in the lung as a result of immune response to Mycobacterium tuberculosis (Mtb) infection. Formation and maintenance of granulomas are essential for control of Mtb infection and are regulated in part by a pro-inflammatory cytokine, tumor necrosis factor-alpha (TNF). To characterize mechanisms that control TNF availability within a TB granuloma, we developed a multi-scale two compartment partial differential equation model that describes a granuloma as a collection of immune cells forming concentric layers and includes TNF/TNF receptor binding and trafficking processes. We used the results of sensitivity analysis as a tool to identify experiments to measure critical model parameters in an artificial experimental model of a TB granuloma induced in the lungs of mice following injection of mycobacterial antigen-coated beads. Using our model, we then demonstrated that the organization of immune cells within a TB granuloma as well as TNF/TNF receptor binding and intracellular trafficking are two important factors that control TNF availability and may spatially coordinate TNF-induced immunological functions within a granuloma. Further, we showed that the neutralization power of TNF-neutralizing drugs depends on their TNF binding characteristics, including TNF binding kinetics, ability to bind to membrane-bound TNF and TNF binding stoichiometry. To further elucidate the role of TNF in the process of granuloma development, our modeling and experimental findings on TNF-associated molecular scale aspects of the granuloma can be incorporated into larger scale models describing the immune response to TB infection. Ultimately, these modeling and experimental results can help identify new strategies for TB disease control/therapy. AD - Department of Chemical Engineering, University of Michigan, Ann Arbor, MI, USA. AN - 20463877 AU - Fallahi-Sichani, M. AU - Schaller, M. A. AU - Kirschner, D. E. AU - Kunkel, S. L. AU - Linderman, J. J. DA - May DO - 10.1371/journal.pcbi.1000778 [doi] DP - Nlm ET - 05/14 KW - Algorithms Animals Apoptosis/physiology Computer Simulation Dendritic Cells/immunology Granuloma/immunology/ metabolism/microbiology/pathology Lymphocytes/immunology Macrophages/immunology Mice Mice, Inbred CBA Models, Biological Mycobacterium tuberculosis Protein Binding Receptors, Tumor Necrosis Factor/metabolism Tuberculin/metabolism Tuberculosis/immunology/ metabolism/pathology Tumor Necrosis Factor-alpha/antagonists & inhibitors/ metabolism LA - eng N1 - Fallahi-Sichani, Mohammad Schaller, Matthew A Kirschner, Denise E Kunkel, Steven L Linderman, Jennifer J PY - 2010 RN - fulltext fulltext_1208 SN - 1553-7358 (Electronic) 1553-734X (Linking) SP - e1000778 ST - Identification of key processes that control tumor necrosis factor availability in a tuberculosis granuloma T2 - PLoS Comput Biol TI - Identification of key processes that control tumor necrosis factor availability in a tuberculosis granuloma UR - http://www.ploscompbiol.org/article/fetchObjectAttachment.action?uri=info%3Adoi%2F10.1371%2Fjournal.pcbi.1000778&representation=PDF VL - 6 ID - 2596 ER - TY - JOUR AB - A two-strain tuberculosis model with general contact rate which allows tuberculosis patients with the drug-sensitive Mycobacterium tuberculosis strain to be treated is presented. The model includes both drug-sensitive and drug-resistant strains. A detailed qualitative analysis about positivity, boundedness, existence, uniqueness and global stability of the equilibria of this model is carried out. Analytical results of the model show that the quantities R(1) and R(2), which represent the basic reproduction numbers of the sensitive and resistant strains, respectively, provide the threshold conditions which determine the competitive outcomes of the two strains. Numerical simulations are also conducted to confirm and extend the analytic results. AD - Lanzhou Univ Technol, Inst Appl Math, Lanzhou 730050, Gansu, Peoples R China Lanzhou Univ, Hosp 1, Dept Pediat, Lanzhou 730000, Peoples R China AN - WOS:000290323800001 AU - Huo, H. F. AU - Dang, S. J. AU - Li, Y. N. DO - Artn 293747 10.1155/2010/293747 J2 - Abstr Appl Anal KW - nonlinear incidence rate epidemic model heterogeneous populations global stability transmission dynamics L1 - internal-pdf://1217555451/Huo-2010-Stability of a Two-Strain Tuberculosi.pdf LA - English N1 - 760ks Times Cited:6 Cited References Count:34 PY - 2010 SN - 1085-3375 ST - Stability of a Two-Strain Tuberculosis Model with General Contact Rate T2 - Abstract and Applied Analysis TI - Stability of a Two-Strain Tuberculosis Model with General Contact Rate UR - ://WOS:000290323800001 http://downloads.hindawi.com/journals/aaa/2010/293747.pdf ID - 4864 ER - TY - JOUR AB - BACKGROUND: The prevalence of tuberculosis (TB) in the elderly is higher than that in the general population, and elderly populations are considered a high-risk group. Currently, annual TB screening of Bacille Calmette-Guerin (BCG)-vaccinated people aged over 65 years is performed by an annual chest x-ray examination (CXR) in Japan. Interferon-gamma release assays (QuantiFERON-TB Gold and QuantiFERON-TB Gold In-Tube [QFT]) are new alternatives to the tuberculin skin test to diagnose latent TB infection (LTBI) that have no cross-reactivity with the BCG vaccine. We evaluated the cost effectiveness of QFT versus CXR versus no screening in BCG-vaccinated elderly populations. METHODS: We constructed a Markov model to evaluate the cost effectiveness of QFT, CXR, and no screening. The target population was a hypothetical cohort of 1000 immunocompetent 65-year-olds, using a societal perspective and a lifetime horizon. All costs and clinical benefits were discounted at a fixed annual rate of 3%. RESULTS: In the base-case analysis, a no-screening strategy resulted in the lowest cost ($US303.51; 14.6475 quality-adjusted life-years [QALYs]) compared with CXR ($US393.22; 14.6477 QALYs) and QFT ($US525.45; 14.6516 QALYs) [year 2008 values]. The sensitivity of QFT, as well as the prevalence of TB and LTBI, influenced the cost effectiveness; when the sensitivity of QFT was higher than 0.89, QFT became more cost effective than providing no screening. As the prevalence of LTBI and TB increased, the QFT strategy became progressively more cost effective. CONCLUSIONS: Providing no routine TB screening is currently the most cost-effective strategy for BCG-vaccinated elderly populations in Japan. There appears to be little role for CXR in TB screening of elderly populations. These findings may be applicable to other countries with intermediate and high TB risks when choosing optimal TB screening of elderly populations. AD - Bunkyo City Public Health Center, Bunkyo City, Tokyo, Japan. Akiko_Kowada@city.bunkyo.lg.jp AN - 20799765 AU - Kowada, A. AU - Deshpande, G. A. AU - Takahashi, O. AU - Shimbo, T. AU - Fukui, T. DA - Aug 1 DO - 10.2165/11538610-000000000-00000 10.2165/11538610-000000000-00000. DP - Nlm ET - 08/31 J2 - Molecular diagnosis & therapy KW - Aged Aged, 80 and over BCG Vaccine/administration & dosage Cost-Benefit Analysis Female Humans Immunologic Tests/ economics Interferon-gamma/ analysis/ immunology Japan Latent Tuberculosis/ diagnosis/immunology/radiography Male Mass Chest X-Ray/ economics Mass Screening/economics Tuberculosis, Pulmonary/ diagnosis/immunology/radiography LA - eng PY - 2010 RN - fulltext fulltext_1208 SN - 1177-1062 (Print) 1177-1062 (Linking) SP - 229-36 ST - Cost effectiveness of interferon-gamma release assay versus chest X-ray for tuberculosis screening of BCG-vaccinated elderly populations T2 - Mol Diagn Ther TI - Cost effectiveness of interferon-gamma release assay versus chest X-ray for tuberculosis screening of BCG-vaccinated elderly populations VL - 14 ID - 2597 ER - TY - JOUR AB - The explosive increase in the number of people infected with tuberculosis (TB), multi drug resistant tuberculosis (MDRTB), and injecting drug users (IDU) HIV/AIDS has become a serious public health challenge in Russia. The World Health Organization is recommending policies including simultaneous use of highly active antiretroviral therapy (HAART) to treat HIV/AIDS and second line drugs to treat MDRTB. We developed a System Dynamics simulation model to represent the dynamic transmission of TB, MDRTB and human immunodeficiency virus (HIV). The model simulated scenarios regarding MDRTB cure rate and HAART coverage, that is the HIV/AIDS population covered by HAART. The results over a 20-year period indicate that reduction in TB and HIV-associated TB deaths would be negligible for HAART coverage up to 50%. The reduction is only significant for HAART coverage of 70% and above. Similarly, high MDRTB cure rate reduces significantly deaths from TB and MDRTB and this reduction is more important as the HAART coverage is increased. Journal of the Operational Research Society (2010) 61, 1238-1248. doi: 10.1057/jors.2009.90 Published online 5 August 2009 AD - Univ Hertfordshire, Sch Business, Hatfield AL10 9AB, Herts, England Univ London Imperial Coll Sci Technol & Med, London, England London Sch Hyg & Trop Med, London WC1, England AN - WOS:000280099900004 AU - Lebcir, R. M. AU - Atun, R. A. AU - Coker, R. J. DA - Aug DO - 10.1057/jors.2009.90 IS - 8 J2 - J Oper Res Soc KW - health service hiv tuberculosis haart system dynamics russia human-immunodeficiency-virus health-care developing-countries incubation period eastern-europe aids treatment public-health samara oblast model transmission LA - English N1 - 628fl Times Cited:4 Cited References Count:33 PY - 2010 SN - 0160-5682 SP - 1238-1248 ST - System Dynamic simulation of treatment policies to address colliding epidemics of tuberculosis, drug resistant tuberculosis and injecting drug users driven HIV in Russia T2 - Journal of the Operational Research Society TI - System Dynamic simulation of treatment policies to address colliding epidemics of tuberculosis, drug resistant tuberculosis and injecting drug users driven HIV in Russia UR - ://WOS:000280099900004 https://link.springer.com/article/10.1057%2Fjors.2009.90 VL - 61 ID - 4852 ER - TY - BOOK A2 - Jiang, Y. A2 - Song, Q. K. A2 - Chen, L. S. A2 - Tan, Y. S. AB - The paper studies the applicability of the impulsive strategy for the stable eradication of tuberculosis (TB). We formulate an infection-age-structured TB model with impulsive drug-treatment. In the model, infected class includes latent, infected with drug-sensitive TB and infected with drug-resistant TB. We look at the effects of impulsive period T and drug-treatment proportion rho on TB dynamics. AD - [Liu, Helong; Li, Lianbing] Xinyang Normal Univ, Coll Math & Informat Sci, Xinyang 464000, Peoples R China. Liu, HL (reprint author), Xinyang Normal Univ, Coll Math & Informat Sci, Xinyang 464000, Peoples R China. liuhelong2004@yahoo.com.cn AN - WOS:000280408600135 AU - Liu, H. L. AU - Li, L. B. CY - Liverpool KW - tuberculosis infection age impulsive period infection-free state stability tuberculosis LA - English N1 - ISI Document Delivery No.: BPZ09 Times Cited: 0 Cited Reference Count: 7 Liu, Helong Li, Lianbing Proceedings Paper 7th Conference on Biological Dynamic System and Stability of Differential Equation May 14-16, 2010 Chongqing, PEOPLES R CHINA 113, academic house, mill lane, wavertree technology park, liverpool, l13 4 ah, england PB - World Acad Union-World Acad Press PY - 2010 SN - 978-1-84626-029-2 SP - 648-653 ST - An Age-Infection-Structured TB Model with Delay and Impulsive Effects T2 - Proceedings of the 7th Conference on Biological Dynamic System and Stability of Differential Equation, Vols I and Ii TI - An Age-Infection-Structured TB Model with Delay and Impulsive Effects UR - ://WOS:000280408600135 ID - 5876 ER - TY - JOUR AB - The statistical data of tuberculosis (TB) cases show seasonal fluctuations in many countries. A TB model incorporating seasonality is developed and the basic reproduction ratio R(0) is defined. It is shown that the disease-free equilibrium is globally asymptotically stable and the disease eventually disappears if R(0)<1, and there exists at least one positive periodic solution and the disease is uniformly persistent if R(0)>1. Numerical simulations indicate that there may be a unique positive periodic solution which is globally asymptotically stable if R(0)>1. Parameter values of the model are estimated according to demographic and epidemiological data in China. The simulation results are in good accordance with the seasonal variation of the reported cases of active TB in China. AD - Department of Mathematics, Xi'an Jiaotong University, Xi'an 710049, China. lujuliu@gmail.com AN - 20063125 AU - Liu, L. AU - Zhao, X. Q. AU - Zhou, Y. DA - May DO - 10.1007/s11538-009-9477-8 [doi] DP - Nlm ET - 01/12 KW - Basic Reproduction Number China/epidemiology Computer Simulation Humans Models, Biological Mycobacterium tuberculosis/ growth & development Seasons Tuberculosis/ epidemiology/microbiology LA - eng N1 - Liu, Luju Zhao, Xiao-Qiang Zhou, Yicang United States Bulletin of mathematical biology Bull Math Biol. 2010 May;72(4):931-52. Epub 2010 Jan 9. PY - 2010 RN - fulltext fulltext_1208 SN - 1522-9602 (Electronic) 0092-8240 (Linking) SP - 931-52 ST - A tuberculosis model with seasonality T2 - Bull Math Biol TI - A tuberculosis model with seasonality UR - http://www.springerlink.com/content/ch168155037172u8/ VL - 72 ID - 2598 ER - TY - JOUR AB - This paper describes a mathematical model for tuberculosis (TB) and discusses its dynamic behavior. The model is novel in that it combines multi-drug resistant TB (MDR-TB) with undetected TB cases. The basic reproduction number, R-0, is calculated. The result shows that the disease-free equilibrium is globally asymptotically stable if R-0 <= 1, and is unstable if R-0 > 1. When R-0 > 1, there also exists a locally asymptotically stable endemic equilibrium. Simulations confirm the analysis, and exhibit that undetected TB cases play an important role. AD - S China Univ Technol, SCUT CUHK Joint Ctr Automat Sci & Engn, Guangzhou 510460, Guangdong, Peoples R China AN - WOS:000290460300159 AU - Liu, Y. Q. AU - Sun, Z. D. DO - Doi 10.1109/Ccdc.2010.5498120 J2 - Chin Cont Decis Conf KW - mycobacterium-tuberculosis transmission dynamics coinfection equilibria diseases LA - English N1 - Buv61 Times Cited:0 Cited References Count:21 Chinese Control and Decision Conference PY - 2010 SN - 1948-9439 SP - 792-797 ST - A New Model for MDR-TB Infection with Undetected TB Cases T2 - 2010 Chinese Control and Decision Conference, Vols 1-5 TI - A New Model for MDR-TB Infection with Undetected TB Cases UR - ://WOS:000290460300159 http://ieeexplore.ieee.org/document/5498120/?reload=true ID - 4865 ER - TY - JOUR AB - Modeling the interaction of Tuberculosis (TB) and AIDS (HIV) drugs in the treatment of the TB/HIV co-infection shows that the treatment of Mtb (Mycobacterium tuberculosis) and AIDS improves. The administration of HIV drugs without TB drugs during co-infection favors the treatment of HIV, but the patient will eventually die of the Mtb opportunistic infection. Reducing the interaction of TB and HIV drugs and increasing the performance (efficiency of inhibition) of Reverse Transcriptase Inhibitors (RTIs) in CD4+ T cells improves the treatment of HIV and leads to the preferential replication of HIV particles in macrophages. The simultaneous administration of TB and HIV drugs is to be recommended for it prevents patients from dying of the Mtb opportunistic infection. AD - [Magombedze, Gesham; Garira, Winston] Natl Univ Sci & Technol, Dept Appl Math, Modeling Biomed Syst Res Grp, Ascot, Bulawayo, Zimbabwe. [Mwenje, Eddie] Natl Univ Sci & Technol, Dept Appl Biol, Modeling Biomed Syst Res Grp, Ascot, Bulawayo, Zimbabwe. Magombedze, G (reprint author), Natl Univ Sci & Technol, Dept Appl Math, Modeling Biomed Syst Res Grp, POB AC 939, Ascot, Bulawayo, Zimbabwe. gmagombedze@gmail.com AN - WOS:000274168800002 AU - Magombedze, G. AU - Garira, W. AU - Mwenje, E. C7 - Pii 918914817 DO - 10.1080/08898480903467241 IS - 1 J2 - Math. Popul. Stud. KW - AIDS co-infection highly active anti-retroviral therapy (HAART) Mycobacterium tuberculosis TB chemotherapy mycobacterium-tuberculosis infection tumor-necrosis-factor hiv-related tuberculosis host immune-response t-cells antituberculosis drugs granuloma-formation healthy-volunteers fusion inhibitors entry inhibitors Demography Mathematics Mathematical Methods In Social Sciences LA - English M3 - Article N1 - ISI Document Delivery No.: 550XX Times Cited: 4 Cited Reference Count: 61 Magombedze, Gesham Garira, Winston Mwenje, Eddie Garira, Winston/N-8804-2016 Garira, Winston/0000-0001-8909-2236; Magombedze, Gesham/0000-0003-2745-3475 South African DST/NRF Center of Excellence in Epidemiological Modeling and Analysis (SACEMA) Gesham Magombedze acknowledges the financial support of the South African DST/NRF Center of Excellence in Epidemiological Modeling and Analysis (SACEMA). 4 0 Taylor & francis inc Philadelphia PY - 2010 SN - 0889-8480 SP - 12-64 ST - Modeling the TB/HIV-1 Co-Infection and the Effects of Its Treatment T2 - Mathematical Population Studies TI - Modeling the TB/HIV-1 Co-Infection and the Effects of Its Treatment UR - ://WOS:000274168800002 VL - 17 ID - 5871 ER - TY - JOUR AB - We aimed to evaluate the incremental cost-effectiveness of engaging private practitioners (PPs) to refer tuberculosis (TB) suspects to public health centers in Jogjakarta, Indonesia. Effectiveness was assessed for TB suspects notified between May 2004 and April 2005. Private practitioners referred 1,064 TB suspects, of which 57.5% failed to reach a health center. The smear-positive rate among patients reaching a health center was 61.8%. Two hundred eighty (280) out of a total of 1,306 (21.4%) new smear-positive cases were enrolled through the PPs strategy. The incremental cost-effectiveness ratio per smear-positive case successfully treated for the PPs strategy was US$351.66 (95% CI 322.84-601.33). On the basis of an acceptability curve using the National TB control program's willingness-to-pay threshold (US$448.61), we estimate the probability that the PPs strategy is cost-effective at 66.8%. The strategy of engaging PPs was incrementally cost-effective, although under specific conditions, most importantly a well-functioning public directly observed treatment, short-course (DOTS) program. AD - Department of Public Health, Faculty of Medicine, Gadjah Mada University, Jogjakarta, Indonesia. yodi_mahendradhata@yahoo.co.uk AN - 20519613 AU - Mahendradhata, Y. AU - Probandari, A. AU - Ahmad, R. A. AU - Utarini, A. AU - Trisnantoro, L. AU - Lindholm, L. AU - van der Werf, M. J. AU - Kimerling, M. AU - Boelaert, M. AU - Johns, B. AU - Van der Stuyft, P. DA - Jun DO - 82/6/1131 [pii] 10.4269/ajtmh.2010.09-0447 ET - 06/04 KW - Antitubercular Agents/*administration & dosage/*therapeutic use Cost-Benefit Analysis Directly Observed Therapy Humans Indonesia/epidemiology Physician's Practice Patterns/*economics Referral and Consultation Tuberculosis/*drug therapy/*epidemiology LA - eng N1 - Mahendradhata, Yodi Probandari, Ari Ahmad, Riris A Utarini, Adi Trisnantoro, Laksono Lindholm, Lars van der Werf, Marieke J Kimerling, Michael Boelaert, Marleen Johns, Benjamin Van der Stuyft, Patrick Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. United States The American journal of tropical medicine and hygiene Am J Trop Med Hyg. 2010 Jun;82(6):1131-9. PY - 2010 RN - fulltext fulltext_1208 SN - 1476-1645 (Electronic) 0002-9637 (Linking) SP - 1131-1139 ST - The incremental cost-effectiveness of engaging private practitioners to refer tuberculosis suspects to DOTS services in Jogjakarta, Indonesia T2 - American Journal of Tropcial Medicine and Hygiene TI - The incremental cost-effectiveness of engaging private practitioners to refer tuberculosis suspects to DOTS services in Jogjakarta, Indonesia UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=20519613http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2877424/pdf/tropmed-82-1131.pdf VL - 82 ID - 2599 ER - TY - JOUR AB - Tuberculosis (TB) is one of the earliest recorded human diseases and still one of the deadliest worldwide. Its causative agent is the bacteria Mycobacterium tuberculosis (Mtb). Cytokine-mediated macrophage activation is a necessary step in control of bacterial growth, and early immunologic events in lymph node and lung are crucial to the outcome of infection, although the factors that influence these environments and the immune response are poorly understood. Our goal is to build the next-generation two-compartmental model of the immune response to provide a gateway to more spatial and mechanistic investigations of M. tuberculosis infection in the LN and lung. Crucial immune factors emerge that affect macrophage populations and inflammation, namely TNF-dependent recruitment and apoptosis, and IL-10 levels. Surprisingly, bacterial load plays a less important role than TNF in increasing the population of infected macrophages and inflammation. Using a mathematical model, it is possible to distinguish the effects of pro-inflammatory (TNF) and anti-inflammatory (IL-10) cytokines on the spectrum of phagocyte populations (macrophages and dendritic cells) in the lung and lymph node. Our results suggest that TNF is a major mediator of recruitment of phagocytes to the lungs. In contrast, IL-10 plays a role in balancing the dominant macrophage phenotype in LN and lung. AD - Department of Microbiology and Immunology, The University of Michigan Medical School, Ann Arbor, MI 48109-0620, USA. simeonem@umich.edu AN - 20510249 AU - Marino, S. AU - Myers, A. AU - Flynn, J. L. AU - Kirschner, D. E. DA - Aug 21 DO - S0022-5193(10)00241-9 [pii] 10.1016/j.jtbi.2010.05.012 [doi] DP - Nlm ET - 06/01 KW - Animals Cell Polarity Dendritic Cells/immunology/microbiology Humans Immunomodulation/immunology Interleukin-10/ immunology Lung/ immunology/microbiology/pathology Lymph Nodes/ immunology/microbiology/pathology Macrophages/cytology/immunology/microbiology Mice Mice, Inbred C57BL Models, Immunological Mycobacterium tuberculosis/immunology Phagocytes/cytology/ immunology Reproducibility of Results T-Lymphocytes/immunology/microbiology Tuberculosis/ immunology Tumor Necrosis Factor-alpha/ immunology LA - eng N1 - Marino, Simeone Myers, Amy Flynn, JoAnne L Kirschner, Denise E HL092853/HL/NHLBI NIH HHS/United States LM00902701/LM/NLM NIH HHS/United States N01 AI050018/AI/NIAID NIH HHS/United States N01 AI50018/AI/NIAID NIH HHS/United States R01 HL071241-08/HL/NHLBI NIH HHS/United States R01 LM009027-03/LM/NLM NIH HHS/United States R01HL71241/HL/NHLBI NIH HHS/United States R33 HL092853-03/HL/NHLBI NIH HHS/United States Research Support, N.I.H., Extramural England Journal of theoretical biology Nihms217396 J Theor Biol. 2010 Aug 21;265(4):586-98. Epub 2010 May 25. PY - 2010 RN - fulltext fulltext_1208 SN - 1095-8541 (Electronic) 0022-5193 (Linking) SP - 586-98 ST - TNF and IL-10 are major factors in modulation of the phagocytic cell environment in lung and lymph node in tuberculosis: a next-generation two-compartmental model T2 - J Theor Biol TI - TNF and IL-10 are major factors in modulation of the phagocytic cell environment in lung and lymph node in tuberculosis: a next-generation two-compartmental model UR - http://ac.els-cdn.com/S0022519310002419/1-s2.0-S0022519310002419-main.pdf?_tid=18a5b01be8b035d5b65dbe99b6609ef6&acdnat=1345012718_f9a3f6428d4664f7ba74c5aa29b37038 VL - 265 ID - 2600 ER - TY - JOUR AU - Okuonghae, D. AU - Aihie, V. U. DO - doi:10.1142/S0218339010003160 PY - 2010 RN - fulltext fulltext_1208 SP - 17-54 ST - OPTIMAL CONTROL MEASURES FOR TUBERCULOSIS MATHEMATICAL MODELS INCLUDING IMMIGRATION AND ISOLATION OF INFECTIVE T2 - Journal of Biological Systems TI - OPTIMAL CONTROL MEASURES FOR TUBERCULOSIS MATHEMATICAL MODELS INCLUDING IMMIGRATION AND ISOLATION OF INFECTIVE UR - http://www.worldscientific.com/doi/abs/10.1142/S0218339010003160 VL - 18 ID - 2601 ER - TY - JOUR AB - This paper presents qualitative and quantitative study of a TB mathematical model to test results from a survey carried out in Benin City, Nigeria. The purpose of the survey was to determine factors that could enhance the case detection rate of tuberculosis. Results from the survey identified four key factors that must be combined for an effective control of TB and increase the case detection rate: effective awareness programme, active cough identification, associated cost factor for treatment of identified cases and effective treatment. The overall effect of these factors on the basic reproduction number under treatment, R(T), of the TB model was considered. In all, a serious concentration on tuberculosis awareness programmes and active cough identification as a marker for someone having TB was shown to significantly reduce the value of the reproduction number, hereby reducing the severity of the disease in the presence of treatment. AD - Department of Mathematics, University of Benin, P.M.B. 1154, Benin City, Edo State, Nigeria. danny.okuonghae@corpus-christi.oxon.org AN - 20937288 AU - Okuonghae, D. AU - Omosigho, S. E. DA - Jan 21 DO - S0022-5193(10)00527-8 [pii] 10.1016/j.jtbi.2010.09.044 [doi] DP - Nlm ET - 10/13 KW - Basic Reproduction Number Computer Simulation Humans Models, Biological Nigeria/epidemiology Tuberculosis/ diagnosis/ epidemiology/therapy Uncertainty LA - eng N1 - Okuonghae, D Omosigho, S E England Journal of theoretical biology J Theor Biol. 2011 Jan 21;269(1):31-45. Epub 2010 Oct 15. PY - 2010 RN - fulltext fulltext_1208 SN - 1095-8541 (Electronic) 0022-5193 (Linking) SP - 31-45 ST - Analysis of a mathematical model for tuberculosis: What could be done to increase case detection T2 - J Theor Biol TI - Analysis of a mathematical model for tuberculosis: What could be done to increase case detection UR - http://ac.els-cdn.com/S0022519310005278/1-s2.0-S0022519310005278-main.pdf?_tid=8fadaf066889020abe397627114b1c58&acdnat=1345012976_71255e4ac825a88815d9584230c81981 VL - 269 ID - 2641 ER - TY - JOUR AD - [Ou, S. -C.] Leader Univ, Dept Comp Sci & Informat Engn, Taipei, Taiwan. [Chung, C. -Y.; Chung, H. -Y.] Natl Cent Univ, Dept Elect Engn, Taipei, Taiwan. AN - WOS:000279630200294 AU - Ou, S. C. AU - Chung, C. Y. AU - Chung, H. Y. DA - Jul J2 - Int. J. Infect. Dis. KW - Infectious Diseases LA - English M3 - Meeting Abstract N1 - ISI Document Delivery No.: 622AK Times Cited: 0 Cited Reference Count: 0 Ou, S. -C. Chung, C. -Y. Chung, H. -Y. Chung, Hung-Yuan/H-8055-2012 Chung, Hung-Yuan/0000-0002-1787-173X 0 2 Elsevier sci ltd Oxford PY - 2010 SN - 1201-9712 SP - S93-S93 ST - Liapunov functions and computer simulation applied to biomathematic model of dynamic system for tuberculosis T2 - International Journal of Infectious Diseases TI - Liapunov functions and computer simulation applied to biomathematic model of dynamic system for tuberculosis UR - ://WOS:000279630200294 VL - 14 ID - 5822 ER - TY - CHAP A2 - Zhu, R. B. A2 - Zhang, Y. C. A2 - Liu, B. X. A2 - Liu, C. F. AB - According the World Health Organization, one third of the world's population is infected with tuberculosis (TB), leading to between two and three million deaths each year. TB is now the second most common cause of death from infectious disease in the world after human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS). Tuberculosis is a leading cause of infectious mortality. Although anti-biotic treatment is available and there is vaccine, tuberculosis levels are rising in many areas of the world. Mathematical models have been used to study tuberculosis in the past and have influenced policy; the spread of HIV and the emergence of drug-resistant TB strains motivate the use of mathematical models today In the recent year, the Biomathmetics has become the main important trend of research dirction which has applied to the epidemic models of disease mechanism, spreading, regulation, and stategy of disease preventing in the field of medical and public health. The papers will apply Lyapunov stability function V (x) to construct a dynamic mathematics models for tuberculosis and to meet the above-mentioned TB disease mechanism,spreading regulation, and stategy of disease preventing in the medical field. The theory of Lyapunov stability function is a general rule and method to examine and determine the stability characteristics of a dynamic system. There are two functions of Lyapunov theory: (a) the Lyapunov indirect method which solves the dynamics differential equations of the constructing system then determines its stability properties, and (b) the Lyapunov direct method which determine the system stability directly via constructing a Lyapunov Energy Function V(x) of the dynamic mathematic model for tuberculosis. Here we will analyse the complex dynamic mathematic model of tuberculosis epidemic and determine its stability property by using the popular Matlab/Simulink software and relative software packages. AD - [Ou, Shih-Ching] Leader Univ, Dept Comp Sci & Informat Engn, Tainan 709, Taiwan. [Chung, Hung-Yuan; Chung, Chun-Yen] Natl Cent Univ, Dept Elect Engn, Jhongli 32001, Taiwan. Ou, SC (reprint author), Leader Univ, Dept Comp Sci & Informat Engn, Tainan 709, Taiwan. chunyen911@gmail.com AN - WOS:000289612900057 AU - Ou, S. C. AU - Chung, H. Y. AU - Chung, C. Y. CY - Berlin KW - Tuberculosis Biomathmetics Lyapunov LA - English N1 - ISI Document Delivery No.: BUK24 Times Cited: 0 Cited Reference Count: 6 Ou, Shih-Ching Chung, Hung-Yuan Chung, Chun-Yen Proceedings Paper International Conference on Information Computing and Applications Oct 15-18, 2010 Tangshan, PEOPLES R CHINA Hebei Polytechn Univ, Hebei Scene Stat Soc, Natl Sci Fdn, Hunan Inst Engn financial support of the National Science Council,Taiwan [NSC 98-2221-E-426-007] The authors wish to thank the financial support of the National Science Council,Taiwan, under Contract NSC 98-2221-E-426-007. Heidelberger platz 3, d-14197 berlin, germany 0302-9743 PB - Springer-Verlag Berlin PY - 2010 SN - 978-3-642-16166-7 SP - 447-+ ST - A Biomathematic Models for Tuberculosis Using Lyapunov Stability Functions T2 - Information Computing and Applications T3 - Lecture Notes in Computer Science TI - A Biomathematic Models for Tuberculosis Using Lyapunov Stability Functions UR - ://WOS:000289612900057 VL - 6377 ID - 5866 ER - TY - JOUR AB - The model herein aims to explore the dynamics of the spread of tuberculosis (TB) in an informal settlement or township. The population is divided into households of various sizes and also based on commuting status. The model dynamics distinguishes between three distinct social patterns: the exposure of commuters during travel, random diurnal interaction and familial exposure at night. Following the general SLIR models, the population is further segmented into susceptible (S), exposed/latently infected (L), active/infectious (I), and recovered (R) individuals. During the daytime, commuters travel on public transport, while non-commuters randomly interact in the community to mimic chance encounters with infectious persons. At night, each family interacts and sleeps together in the home. The risk of exposure to TB is based on the proximity, duration, and frequency of encounters with infectious persons. The model is applied to a hypothetical population to explore the effects of different intervention strategies including vaccination, wearing of masks during the commute, prophylactic treatment of latent infections and more effective case-finding and treatment. The most important findings of the model are: (1) members of larger families are responsible for more disease transmissions than those from smaller families, (2) daily commutes on public transport provide ideal conditions for transmission of the disease, (3) improved diagnosis and treatment has the greatest impact on the spread of the disease, and (4) detecting TB at the first clinic visit, when patients are still smear negative, is key. (C) 2010 Elsevier Ltd. All rights reserved. AD - Univ Nebraska, Dept Chem & Biomol Engn, Lincoln, NE 68588 USA Univ Nebraska, Med Ctr, Dept Internal Med, Omaha, NE 68198 USA AN - WOS:000278721200003 AU - Pienaar, E. AU - Fluitt, A. M. AU - Whitney, S. E. AU - Freifeld, A. G. AU - Viljoen, H. J. DA - Apr DO - 10.1016/j.compbiolchem.2010.03.003 IS - 2 J2 - Comput Biol Chem KW - mathematical model tuberculosis multiple cluster urban community commute drug-resistant tuberculosis exogenous reinfection infectious-diseases south-africa epidemics dynamics efficacy population prevalence protection L1 - internal-pdf://1884756587/Pienaar-2010-A model of tuberculosis transmiss.pdf LA - English N1 - 610hb Times Cited:7 Cited References Count:36 PY - 2010 SN - 1476-9271 SP - 86-96 ST - A model of tuberculosis transmission and intervention strategies in an urban residential area T2 - Computational Biology and Chemistry TI - A model of tuberculosis transmission and intervention strategies in an urban residential area UR - ://WOS:000278721200003 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3039429/pdf/nihms266749.pdf VL - 34 ID - 4866 ER - TY - JOUR AB - The complex web of interactions between the host immune system and the pathogen determines the outcome of any infection. A computational model of this interaction network, which encodes complex interplay among host and bacterial components, forms a useful basis for improving the understanding of pathogenesis, in filling knowledge gaps and consequently to identify strategies to counter the disease. We have built an extensive model of the Mycobacterium tuberculosis host-pathogen interactome, consisting of 75 nodes corresponding to host and pathogen molecules, cells, cellular states or processes. Vaccination effects, clearance efficiencies due to drugs and growth rates have also been encoded in the model. The system is modelled as a Boolean network. Virtual deletion experiments, multiple parameter scans and analysis of the system's response to perturbations, indicate that disabling processes such as phagocytosis and phagolysosome fusion or cytokines such as TNF-alpha and IFN-gamma, greatly impaired bacterial clearance, while removing cytokines such as IL-10 alongside bacterial defence proteins such as SapM greatly favour clearance. Simulations indicate a high propensity of the pathogen to persist under different conditions. AD - Bioinformatics Centre, Indian Institute of Science, Bangalore - 560012, India. nchandra@serc.iisc.ernet.in. AN - 20174680 AU - Raman, K. AU - Bhat, A. G. AU - Chandra, N. DA - Mar DO - 10.1039/b912129c [doi] DP - Nlm ET - 02/23 KW - Computer Simulation Cytokines/genetics Gene Knockout Techniques Host-Pathogen Interactions/genetics/immunology/ physiology Humans Immune System Phenomena Models, Biological Mycobacterium tuberculosis/genetics/immunology/ physiology Signal Transduction Systems Biology/ methods Tuberculosis/immunology/metabolism/ microbiology Virulence Factors LA - eng N1 - Raman, Karthik Bhat, Ashwini Gurudas Chandra, Nagasuma Research Support, Non-U.S. Gov't England Molecular bioSystems Mol Biosyst. 2010 Mar;6(3):516-30. Epub 2009 Dec 14. PY - 2010 RN - fulltext fulltext_1208 SN - 1742-2051 (Electronic) 1742-2051 (Linking) SP - 516-30 ST - A systems perspective of host-pathogen interactions: predicting disease outcome in tuberculosis T2 - Mol Biosyst TI - A systems perspective of host-pathogen interactions: predicting disease outcome in tuberculosis UR - http://pubs.rsc.org/en/Content/ArticleLanding/2010/MB/b912129c VL - 6 ID - 2602 ER - TY - JOUR AB - RATIONALE: Isoniazid preventive therapy is effective in reducing the risk of tuberculosis (TB) in persons living with HIV (PLWH); however, screening must exclude TB disease before initiating therapy. Symptom screening alone may be insufficient to exclude TB disease in PLWH because some PLWH with TB disease have no symptoms. The addition of chest radiography (CXR) may improve disease detection. OBJECTIVES: The objective of the present analysis was to compare the costs and effects of the addition of CXR to the symptom screening process against the costs and effects of symptom screening alone. METHODS: Using data from Botswana, a decision analytic model was used to compare a "Symptom only" policy against a "Symptom+CXR" policy. The outcomes of interest were cost, death, and isoniazid- and multidrug-resistant TB in a hypothetical cohort of 10,000 PLWH. MEASUREMENTS AND MAIN RESULTS: The Symptom+CXR policy prevented 16 isoniazid- and 0.3 multidrug-resistant TB cases; however, because of attrition from the screening process, there were 98 excess cases of TB, 15 excess deaths, and an additional cost of U.S. $127,100. The Symptom+CXR policy reduced deaths only if attrition was close to zero; however, to eliminate attrition the cost would be U.S. $2.8 million per death averted. These findings did not change in best- and worst-case scenario analyses. CONCLUSIONS: In Botswana, a policy with symptom screening only preceding isoniazid-preventive therapy initiation prevents more TB and TB-related deaths, and uses fewer resources, than a policy that uses both CXR and symptom screening. AD - Division of TB Elimination, Centers for Disease Control and Prevention/PHS, 1600 Clifton Rd., Atlanta, GA 30333, USA. tts0@cdc.gov AN - 21148723 AU - Samandari, T. AU - Bishai, D. AU - Luteijn, M. AU - Mosimaneotsile, B. AU - Motsamai, O. AU - Postma, M. AU - Hubben, G. DA - Apr 15 DO - 201004-0620OC [pii] 10.1164/rccm.201004-0620OC ET - 12/15 KW - Antitubercular Agents/economics/therapeutic use Botswana/epidemiology Cost-Benefit Analysis Drug Resistance, Multiple, Bacterial Health Care Costs/*statistics & numerical data Humans Isoniazid/economics/therapeutic use Mass Chest X-Ray/*economics Models, Economic Tuberculosis, Pulmonary/drug therapy/economics/*prevention & control/radiography L1 - internal-pdf://0776974818/Samandari-2010-Costs and consequences of addit.pdf LA - eng N1 - Samandari, Taraz Bishai, David Luteijn, Michiel Mosimaneotsile, Barudi Motsamai, Oaitse Postma, Maarten Hubben, Gijs R24 HD042854-09/HD/NICHD NIH HHS/United States Research Support, U.S. Gov't, P.H.S. United States American journal of respiratory and critical care medicine Am J Respir Crit Care Med. 2011 Apr 15;183(8):1103-11. Epub 2010 Dec 10. PY - 2010 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1535-4970 (Electronic) 1073-449X (Linking) SP - 1103-11 ST - Costs and consequences of additional chest x-ray in a tuberculosis prevention program in Botswana T2 - Am J Respir Crit Care Med TI - Costs and consequences of additional chest x-ray in a tuberculosis prevention program in Botswana UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=21148723http://ajrccm.atsjournals.org/content/183/8/1103.longhttp://www.ncbi.nlm.nih.gov/pmc/articles/PMC3159079/pdf/AJRCCM18381103.pdf https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3159079/pdf/AJRCCM18381103.pdf VL - 183 ID - 2644 ER - TY - CHAP A2 - Gumel, A. B. A2 - Lenhart, S. AB - Curtailing the public health crises generated by the TB/HIV co-pandemic poses many challenges, including monitoring difficulties that complicate our ability to accurately predict the efficacy of public health interventions. Unfortunately, the dire and urgent need to inform policy makers on the individual and population benefits to be obtained from different disease control measures may result in our prioritizing predicting per se, over conducting in-depth system studies that can maximize our ability to properly address the question(s) posed. In this chapter we illustrate these difficulties and exemplify how analytical studies can be used not only as a powerful predictive tool that can help guide public health policy, but also as a means of gaining important insight into the system's functioning that, in turn, can help the monitoring of pandemics. We present in detail the mathematical, statistical and computational approach and methodology behind our recent research focused on evaluating the potential public health benefits to be derived from reducing TB treatment duration from the standard 6- to 8-month treatments to a 2-month treatment in areas of high HIV prevalence. Because of the considerable uncertainties and spatial and temporal heterogeneity in parameter values we conducted a calibration to historical TB/HIV trends that increased the validity of our predictive results for high HIV prevalence areas. Unexpectedly, our calibration unveiled incongruent epidemiological patterns between the two interacting diseases in Kenya, which led us to evaluate reported TB/HIV co-dynamics for the whole of Africa with a new statistic that quantifies the relative change in TB numbers as compared to HIV numbers. Our initial analysis of pan-African patterns placed Kenya as an outlier. However, Kenyan TB and HIV estimates have since been revised, and now the relative change in the co-dynamics of the two diseases place Kenya in a more intermediate position. We additionally conducted a sensitivity analysis to evaluate which parameters had a greater influence on the output variables of choice. In this chapter we briefly explain the results of our model predictions and of our sensitivity analysis focusing on the general approach and methods because many of the lessons learned related to the reasoning and steps we followed, and not exclusively to the results of our investigation. Thus, here our final conclusions and recommendations are geared towards the analytical process more than the public health implications of our studies. Most importantly, this study taught us the power of contrasting trends of interacting diseases in global disease monitoring and control. This is particularly so for such a complex co-pandemic as TB/HIV, where our analysis of the joint co-dynamics provided important insights into the individual epidemiology of each disease. AD - [Sanchez, Maria S.] Univ Calif Berkeley, Dept Environm Sci Policy & Management, Berkeley, CA 94720 USA. Penn State Univ, Ctr Infect Dis Dynam, University Pk, PA 16802 USA. WHO, Stop TB Dept, CH-1211 Geneva 27, Switzerland. Sanchez, MS (reprint author), Univ Calif Berkeley, Dept Environm Sci Policy & Management, Berkeley, CA 94720 USA. AN - WOS:000294873400007 AU - Sanchez, M. S. AU - Lloyd-Smith, J. O. AU - Williams, B. G. AU - Getz, W. M. CY - Providence KW - active antiretroviral therapy sub-saharan africa tuberculosis-control hiv-infection mycobacterium-tuberculosis control strategies south-africa high-rates kenya transmission LA - English N1 - ISI Document Delivery No.: BWU51 Times Cited: 0 Cited Reference Count: 96 Sanchez, Maria S. Lloyd-Smith, James O. Williams, Brian G. Getz, Wayne M. Proceedings Paper US-African-Advanced-Study-Institute Conference on Mathematical Modeling of Infectious Diseases in Africa DIMACS Workshop on Mathematical Modeling of Infectious Diseases in Africa Jun 11-22, 2007 Jun 25-27, 2007 African Inst Math Sci, Muizenberg, SOUTH AFRICA S African Ctr Epidemiol Model Anal, Stellenbosch, SOUTH AFRICA AIMS, DIMACS, US Natl Sci Fdn, SACEMA NIH-NIDA; James S. McDonnell Foundation 21st Century Science Initiative; Global Alliance for TB Drug Development; SACEMA; South African Center for Epidemiological Modeling and Analysis We thank anonymous reviewers and David Bangsberg, Jason Barbour, Frank Cobelens, Kathryn DeRiemer, Judy Hahn, John Hargrove, Philip Hopewell, Gwynne Oosterbaan, Perry de Valpine, Francois Venter, Suzanne Verver, and members of Wayne Getzs lab, for their help and orientation. We would especially like to thank the Kenyan public health authorities and all persons participating in the data collection. This research was supported by NIH-NIDA (MSS and WMG), the James S. McDonnell Foundation 21st Century Science Initiative (WMG), the Global Alliance for TB Drug Development (WMG), and SACEMA, the South African Center for Epidemiological Modeling and Analysis (WMG). P.o. box 6248, providence, ri 02940 usa 1052-1798 PB - Amer Mathematical Soc PY - 2010 SN - 978-0-8218-4384-0 SP - 135-+ ST - Using mathematical models to monitor and evaluate the impact of public health interventions on epidemics: the case of the TB/HIV co-pandemic in Africa T2 - Modeling Paradigms and Analysis of Disease Transmission Models T3 - DIMACS-Series in Discrete Mathematics and Theoretical Computer Science TI - Using mathematical models to monitor and evaluate the impact of public health interventions on epidemics: the case of the TB/HIV co-pandemic in Africa UR - ://WOS:000294873400007 VL - 75 ID - 5872 ER - TY - JOUR AB - Up to now, the effects of having heterogeneous networks of contacts have been studied mostly for diseases which are not persistent in time, i.e., for diseases where the infectious period can be considered very small compared to the lifetime of an individual. Moreover, all these previous results have been obtained for closed populations, where the number of individuals does not change during the whole duration of the epidemics. Here, we go one step further and analyze, both analytically and numerically, a radically different kind of diseases: those that are persistent and can last for an individual's lifetime. To be more specific, we particularize to the case of tuberculosis' (TB) infection dynamics, where the infection remains latent for a period of time before showing up and spreading to other individuals. We introduce an epidemiological model for TB-like persistent infections taking into account the heterogeneity inherent to the population structure. This sort of dynamics introduces new analytical and numerical challenges that we are able to sort out. Our results show that also for persistent diseases the epidemic threshold depends on the ratio of the first two moments of the degree distribution so that it goes to zero in a class of scale-free networks when the system approaches the thermodynamic limit. AD - Institute for Biocomputation and Physics of Complex Systems (BIFI), University of Zaragoza, Zaragoza 50009, Spain. AN - 20866298 AU - Sanz, J. AU - Floria, L. M. AU - Moreno, Y. DA - May DO - 10.1103/PhysRevE.81.056108 IS - 5 Pt 2 N1 - Sanz, J Floria, L M Moreno, Y eng 2010/09/28 06:00 Phys Rev E Stat Nonlin Soft Matter Phys. 2010 May;81(5 Pt 2):056108. Epub 2010 May 25. PY - 2010 SN - 1550-2376 (Electronic) 1539-3755 (Linking) SP - 056108 ST - Spreading of persistent infections in heterogeneous populations T2 - Phys Rev E Stat Nonlin Soft Matter Phys TI - Spreading of persistent infections in heterogeneous populations UR - https://www.ncbi.nlm.nih.gov/pubmed/20866298 VL - 81 ID - 2250 ER - TY - JOUR AB - Background: Several diseases, many of which nowadays pandemic, consist of multifactorial pathologies. Paradigmatic examples come from the immune response to pathogens, in which cases the effects of different infections combine together, yielding complex mutual feedback, often a positive one that boosts infection progression in a scenario that can easily become lethal. HIV is one such infection, which weakens the immune system favouring the insurgence of opportunistic infections, amongst which Tuberculosis (TB). The treatment with antiretroviral therapies has shown effective in reducing mortality. An in-depth understanding of complex systems, like the one consisting of HIV, TB and related therapies, is an open great challenge, on the boundaries of bioinformatics, computational and systems biology. Results: We present a simplified formalisation of the highly dynamic system consisting of HIV, TB and related therapies, at the cellular level. The progression of the disease (AIDS) depends hence on interactions between viruses, cells, chemokines, the high mutation rate of viruses, the immune response of individuals and the interaction between drugs and infection dynamics. We first discuss a deterministic model of dual infection (HIV and TB) which is able to capture the long-term dynamics of CD4 T cells, viruses and Tumour Necrosis Factor (TNF). We contrast this model with a stochastic approach which captures intrinsic fluctuations of the biological processes. Furthermore, we also integrate automated reasoning techniques, i.e. probabilistic model checking, in our formal analysis. Beyond numerical simulations, model checking allows general properties (effectiveness of anti-HIV therapies) to be verified against the models by means of an automated procedure. Our work stresses the growing importance and flexibility of model checking techniques in bioinformatics. In this paper we i) describe HIV as a complex case of infectious diseases; ii) provide a number of different formal descriptions that suitably account for aspects of interests; iii) suggest that the integration of different models together with automated reasoning techniques can improve the understanding of infections and therapies through formal analysis methodologies. Conclusion: We argue that the described methodology suitably supports the study of viral infections in a formal, automated and expressive manner. We envisage a long-term contribution of this kind of approaches to clinical Bioinformatics and Translational Medicine. AD - [Sorathiya, Anil; Lio, Pietro] Univ Cambridge, Comp Lab, Cambridge CB3 0FD, England. [Bracciali, Andrea] Univ Pisa, Dept Comp Sci, I-56127 Pisa, Italy. Sorathiya, A (reprint author), Univ Cambridge, Comp Lab, William Gates Bldg,15 JJ Thomson Ave, Cambridge CB3 0FD, England. anilkumar.sorathiya@cl.cam.ac.uk; braccia@di.unipi.it; pietro.lio@cl.cam.ac.uk AN - WOS:000277537900046 AU - Sorathiya, A. AU - Bracciali, A. AU - Lio, P. C7 - S67 DO - 10.1186/1471-2105-11-s1-s67 J2 - BMC Bioinformatics KW - immunodeficiency-virus type-1 necrosis-factor-alpha mycobacterium-tuberculosis immune-system in-vivo infection dynamics expression receptor cells Biochemistry & Molecular Biology Biotechnology & Applied Microbiology Mathematical & Computational Biology LA - English M3 - Article N1 - ISI Document Delivery No.: 594KZ Times Cited: 3 Cited Reference Count: 43 Sorathiya, Anil Bracciali, Andrea Lio, Pietro Bracciali, Andrea/0000-0003-1451-9260 Ec The authors wish to thank the anonymous referees for their helpful comments on a previous version of this paper. This project is partially supported by EC IST SOCIALNETS and WADA projects. 3 1 4 Biomed central ltd London PY - 2010 SN - 1471-2105 SP - 11 ST - Formal reasoning on qualitative models of coinfection of HIV and Tuberculosis and HAART therapy T2 - Bmc Bioinformatics TI - Formal reasoning on qualitative models of coinfection of HIV and Tuberculosis and HAART therapy UR - ://WOS:000277537900046 VL - 11 ID - 5863 ER - TY - JOUR AB - High tuberculosis (TB) prevalence in Papua New Guinea (PNG) is a serious public health concern. The epidemic in this region is exacerbated by the presence of drug-resistant TB strains as well as HIV infection. This presents a public health threat not only locally but also to Australia due to the high potential for cross-border transmission between PNG's Western Province and the Australian Torres Strait Islands. We present two mathematical models of TB in the Western Province: a simple model of the underlying TB dynamics, and a detailed model which accounts for the additional effects of HIV and drug resistance. The detailed model is used to make quantitative predictions about the impact of expanding the TB case detection rate under the Directly Observed Treatment, Short-course treatment regimen. This paper provides a framework for future investigation into the economic costs and public health benefits of potential TB interventions in this region, with the eventual aim of providing recommendations to guide policy makers in both PNG and Australia. AD - Australian Natl Univ, Natl Ctr Epidemiol & Populat Hlth, Canberra, ACT 0200, Australia Univ Western Australia, Perth, WA 6009, Australia AN - WOS:000291051300003 AU - Thomas, E. G. AU - Barrington, H. E. AU - Lokuge, K. M. AU - Mercer, G. N. DA - Jul DO - 10.1017/S1446181111000587 IS - 1 J2 - Anziam J KW - tuberculosis drug resistant hiv papua new guinea mathematical model intrinsic transmission dynamics multidrug-resistant mycobacterium-tuberculosis strategies epidemic cost tb L1 - internal-pdf://2251111410/Thomas-2010-Modelling the Spread of Tuberculos.pdf LA - English N1 - 769xj Times Cited:5 Cited References Count:48 PY - 2010 SN - 1446-1811 SP - 26-45 ST - Modelling the Spread of Tuberculosis, Including Drug Resistance and Hiv: A Case Study in Papua New Guinea's Western Province T2 - Anziam Journal TI - Modelling the Spread of Tuberculosis, Including Drug Resistance and Hiv: A Case Study in Papua New Guinea's Western Province UR - ://WOS:000291051300003 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/C2BBAFB69AC59AEB25B63E95C1C471F3/S1446181111000587a.pdf/div-class-title-modelling-the-spread-of-tuberculosis-including-drug-resistance-and-hiv-a-case-study-in-papua-new-guinea-s-western-province-div.pdf VL - 52 ID - 4880 ER - TY - JOUR AB - BACKGROUND: Indian guidelines recommend routine referral for HIV testing of all tuberculosis (TB) patients in the nine states with the highest HIV prevalence, and selective referral for testing elsewhere. We assessed the clinical impact and cost-effectiveness of alternative HIV testing referral strategies among TB patients in India. METHODS AND FINDINGS: We utilized a computer model of HIV and TB disease to project outcomes for patients with active TB in India. We compared life expectancy, cost, and cost-effectiveness for three HIV testing referral strategies: 1) selective referral for HIV testing of those with increased HIV risk, 2) routine referral of patients in the nine highest HIV prevalence states with selective referral elsewhere (current standard), and 3) routine referral of all patients for HIV testing. TB-related data were from the World Health Organization. HIV prevalence among TB patients was 9.0% in the highest prevalence states, 2.9% in the other states, and 4.9% overall. The selective referral strategy, beginning from age 33.50 years, had a projected discounted life expectancy of 16.88 years and a mean lifetime HIV/TB treatment cost of US$100. The current standard increased mean life expectancy to 16.90 years with additional per-person cost of US$10; the incremental cost-effectiveness ratio was US$650/year of life saved (YLS) compared to selective referral. Routine referral of all patients for HIV testing increased life expectancy to 16.91 years, with an incremental cost-effectiveness ratio of US$730/YLS compared to the current standard. For HIV-infected patients cured of TB, receiving antiretroviral therapy increased survival from 4.71 to 13.87 years. Results were most sensitive to the HIV prevalence and the cost of second-line antiretroviral therapy. CONCLUSIONS: Referral of all patients with active TB in India for HIV testing will be both effective and cost-effective. While effective implementation of this strategy would require investment, routine, voluntary HIV testing of TB patients in India should be recommended. AD - Division of General Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA. luhler@partners.org AU - Uhler, L. M. AU - Kumarasamy, N. AU - Mayer, K. H. AU - Saxena, A. AU - Losina, E. AU - Muniyandi, M. AU - Stoler, A. W. AU - Lu, Z. AU - Walensky, R. P. AU - Flanigan, T. P. AU - Bender, M. A. AU - Freedberg, K. A. AU - Swaminathan, S. AU - investigators, Cepac International DO - 10.1371/journal.pone.0012747 KW - Adult Anti-HIV Agents/economics/therapeutic use Antitubercular Agents/therapeutic use Cost-Benefit Analysis Female HIV Infections/complications/diagnosis/drug therapy/economics Health Care Costs Humans India Male Middle Aged Tuberculosis/complications/drug therapy N1 - GR: K24 AI062476/AI/NIAID NIH HHS/United States; GR: R01 AI058736/AI/NIAID NIH HHS/United States; JID: 101285081; 0 (Anti-HIV Agents); 0 (Antitubercular Agents); OID: NLM: PMC2940842; 2010/04/29 [received]; 2010/08/20 [accepted]; 2010/09/16 [epublish]; epublish PY - 2010 RN - fulltext fulltext_1208 SN - 1932-6203; 1932-6203 SP - e12747 ST - Cost-effectiveness of HIV testing referral strategies among tuberculosis patients in India T2 - PloS one TI - Cost-effectiveness of HIV testing referral strategies among tuberculosis patients in India UR - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2940842/pdf/pone.0012747.pdf VL - 5 Y2 - Sep 16 ID - 2603 ER - TY - JOUR AB - BACKGROUND: There is good evidence that diabetes is a risk factor for pulmonary tuberculosis. In England, the rates of both diabetes and tuberculosis vary markedly by ethnic group. OBJECTIVE: To estimate the proportion of incident cases of pulmonary tuberculosis attributable to diabetes (population attributable fraction, PAF) for Asian, black and white men and women aged > or = 15 years in England. METHODS: An epidemiological model was constructed using data on the incidence of tuberculosis, the prevalence of diabetes, the population structure for 2005 and the age-specific relative risk of tuberculosis associated with diabetes from a large cohort study. RESULTS: The estimated PAF of diabetes for pulmonary tuberculosis is highest for Asian men (19.6%, 95% CI 10.9% to 33.1%) and women (14.2%, 95% CI 7.1% to 26.5%). The PAF for all ages is similar in white and black men (6.9%, 95% CI 3.1% to 12.4% and 7.4%, 95% CI 4.6% to 12.9%, respectively) and women (8.2%, 95% CI 3.0% to 15.6% and 8.9%, 95% CI 5.3% to 15.6%, respectively). The similarity of these overall figures, despite a higher prevalence of diabetes in the black population, reflects a much younger mean age of pulmonary tuberculosis in the black population. Overall, of 3461 new cases of pulmonary tuberculosis in England in 2005, 384 (202-780) were estimated to be attributable to diabetes. CONCLUSION: Given the nature of the data available, considerable uncertainty surrounds these estimates. Nonetheless, they highlight the potential importance of diabetes as a risk factor for pulmonary tuberculosis, particularly in groups at high risk of both diseases. Further research to examine the implications of these findings for tuberculosis control is urgently needed. AD - Institute of Health and Society, Newcastle University, Newcastle upon Tyne NE2 4HH, UK. AN - 20421330 AU - Walker, C. AU - Unwin, N. DA - Jul DO - 10.1136/thx.2009.128223 IS - 7 KW - Adolescent Adult African Continental Ancestry Group/statistics & numerical data Age Distribution Aged Asian Continental Ancestry Group/statistics & numerical data Diabetes Complications/ethnology Diabetes Mellitus/*ethnology England/epidemiology Epidemiologic Methods European Continental Ancestry Group/statistics & numerical data Female Humans Male Middle Aged Opportunistic Infections/complications/*ethnology Sex Distribution Tuberculosis, Pulmonary/complications/*ethnology Young Adult N1 - Walker, Caron Unwin, Nigel eng England 2010/04/28 06:00 Thorax. 2010 Jul;65(7):578-81. doi: 10.1136/thx.2009.128223. Epub 2010 Apr 26. PY - 2010 SN - 1468-3296 (Electronic) 0040-6376 (Linking) SP - 578-81 ST - Estimates of the impact of diabetes on the incidence of pulmonary tuberculosis in different ethnic groups in England T2 - Thorax TI - Estimates of the impact of diabetes on the incidence of pulmonary tuberculosis in different ethnic groups in England UR - https://www.ncbi.nlm.nih.gov/pubmed/20421330 VL - 65 ID - 2251 ER - TY - CHAP A2 - Michael, E. A2 - Spear, R. C. AB - Despite the infectious agent that causes tuberculosis having been discovered in 1882, many aspects of the natural history and transmission dynamics of TB are still not fully understood. This is reflected in differences in the structures of mathematical models of TB, which in turn produce differences in the predicted impacts of interventions. Gaining a greater understanding of TB transmission dynamics requires further empirical laboratory and field work, mathematical modelling and interaction between them. Modelling can be used to quantify uncertainty due to different gaps in our knowledge to help identify research priorities. Fortunately, the present moment is an exciting time for TB epidemiology, with rapid progress being made in applying new mathematical modelling techniques, new tools for TB diagnosis and genetic analysis and a growing interest in developing more-effective public-health interventions. AD - [White, Peter J.] Hlth Protect Agcy Ctr Infect, Modelling & Econ Unit, London NW9 5EQ, England. [White, Peter J.] Univ London Imperial Coll Sci Technol & Med, Fac Med, Dept Infect Dis Epidemiol, MRC Ctr Outbreak Anal & Modelling, London W2 1PG, England. White, PJ (reprint author), Hlth Protect Agcy Ctr Infect, Modelling & Econ Unit, 61 Colindale Ave, London NW9 5EQ, England. peter.white@hpa.org.uk AN - WOS:000277148900009 AU - White, P. J. AU - Garnett, G. P. CY - Berlin KW - drug-resistant tuberculosis intrinsic transmission dynamics public-health impact new-york-city mycobacterium-tuberculosis exogenous reinfection molecular epidemiology heterogeneous populations amplification dynamics recurrent tuberculosis LA - English N1 - ISI Document Delivery No.: BOO44 Times Cited: 7 Cited Reference Count: 131 White, Peter J. Garnett, Geoff P. Article; Book Chapter Garnett, Geoffrey/A-9312-2008 Heidelberger platz 3, d-14197 berlin, germany 0065-2598 PB - Springer-Verlag Berlin PY - 2010 SN - 978-1-4419-6063-4 SP - 127-140 ST - Adv.Exp.Med.Biol. T2 - Modelling Parasite Transmission and Control T3 - Advances in Experimental Medicine and Biology TI - Mathematical Modelling of the Epidemiology of Tuberculosis UR - ://WOS:000277148900009 VL - 673 ID - 5873 ER - TY - JOUR AB - HIV has increased the incidence of tuberculosis (TB) by up to sevenfold in African countries, but antiretroviral therapy (ART) reduces the incidence of AIDS-related TB. We use a mathematical model to investigate the short-term and long-term impacts of ART on the incidence of TB, assuming that people are tested for HIV once a year, on average, and start ART at a fixed time after HIV seroconversion or at a fixed CD4(+) cell count. We fit the model to trend data on HIV prevalence and TB incidence in nine countries in sub-Saharan Africa. If HIV-positive people start ART within 5 y of seroconversion, the incidence of AIDS-related TB in 2015 will be reduced by 48% (range: 37-55%). Long-term reductions depend sensitively on the delay to starting ART. If treatment is started 5, 2, or 1 y after HIV seroconversion, or as soon as people test positive, the incidence in 2050 will be reduced by 66% (range: 57-80%), 95% (range: 93-96%), 97.7% (range: 96.9-98.2%) and 98.4% (range: 97.8-98.9%), respectively. In the countries considered here, early ART could avert 0.71 +/- 0.36 [95% confidence interval (CI)] million of 3.4 million cases of TB between 2010 and 2015 and 5.8 +/- 2.9 (95% CI) million of 15 million cases between 2015 and 2050. As more countries provide ART at higher CD4(+) cell counts, the impact on TB should be investigated to test the predictions of this model. AD - South African Centre for Epidemiological Modelling and Analysis, Stellenbosch 7600, South Africa. briangerardwilliams@gmail.com AN - 20974976 AU - Williams, B. G. AU - Granich, R. AU - De Cock, K. M. AU - Glaziou, P. AU - Sharma, A. AU - Dye, C. DA - Nov 9 DO - 1005660107 [pii] 10.1073/pnas.1005660107 [doi] DP - Nlm ET - 10/27 KW - Acquired Immunodeficiency Syndrome/ complications/drug therapy Africa/epidemiology Anti-Retroviral Agents/ therapeutic use HIV Seropositivity Humans Incidence Models, Statistical Time Factors Tuberculosis/drug therapy/epidemiology/etiology/ prevention & control LA - eng N1 - Williams, Brian G Granich, Reuben De Cock, Kevin M Glaziou, Philippe Sharma, Abhishek Dye, Christopher United States Proceedings of the National Academy of Sciences of the United States of America Proc Natl Acad Sci U S A. 2010 Nov 9;107(45):19485-9. Epub 2010 Oct 25. PY - 2010 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1091-6490 (Electronic) 0027-8424 (Linking) SP - 19485-9 ST - Antiretroviral therapy for tuberculosis control in nine African countries T2 - Proc Natl Acad Sci U S A TI - Antiretroviral therapy for tuberculosis control in nine African countries UR - http://www.pnas.org/content/107/45/19485.full.pdf VL - 107 ID - 2604 ER - TY - JOUR AB - BACKGROUND: Tuberculosis transmission is determined by contact between infectious and susceptible individuals. A recent study reported a 4% annual risk of child tuberculosis infection in a southern African township. A model was used to explore the interactions between prevalence of adult tuberculosis infection, adult-to-child contacts, and household ventilation, which could result in such a high annual risk of tuberculosis infection. METHODS: Number of residents per household and tuberculosis incidence were derived from a household census and community tuberculosis registers. Using the Wells-Riley equation and probability analyses of contact between infectious adults with tuberculosis and preschool children, we estimated the annual risk of tuberculosis infection within and outside of the home. RESULTS: There was a mean of 2.2 adults per child-containing household with a 1.35% annual adult smear-positive tuberculosis notification rate. The maximal household annual risk of tuberculosis infection was 3%, which was primarily determined by the number of resident adults. Transmission risk outside the home increased with increasing number of households visited. Transmission probabilities were sensitive to exposure time, ventilation, and period of adult infectivity. The benefits of increased ventilation were greatest when the period of infectivity was reduced. Similar reductions in household transmission could be achieved by increasing ventilation from 2 to 6 air changes/hour or by separating child and adult sleeping areas. CONCLUSIONS: The annual risk of tuberculosis infection of preschool children predominantly results from infectious residents in the home. However, even with limited social interactions, a substantial proportion of transmissions may occur from nonresident adults. The benefits of increased ventilation are maximized when the period of infectivity is reduced by prompt treatment of source cases. AD - Desmond Tutu HIV Centre, Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, Faculty of Health Sciences, Cape Town, South Africa. robin.wood@hiv-research.org.za AN - 20604716 AU - Wood, R. AU - Johnstone-Robertson, S. AU - Uys, P. AU - Hargrove, J. AU - Middelkoop, K. AU - Lawn, S. D. AU - Bekker, L. G. DA - Aug 15 DO - 10.1086/655129 [doi] DP - Nlm ET - 07/08 KW - Adolescent Adult Child Child, Preschool Community-Acquired Infections/ epidemiology/ transmission Family Health Humans Infant Infant, Newborn Models, Statistical Prevalence Risk Assessment South Africa/epidemiology Tuberculosis/ epidemiology/ transmission LA - eng N1 - Wood, Robin Johnstone-Robertson, Simon Uys, Pieter Hargrove, John Middelkoop, Keren Lawn, Stephen D Bekker, Linda-Gail 1U19AI53217-01/AI/NIAID NIH HHS/United States A1058736-01A1/PHS HHS/United States R01 AI058736-01A1/AI/NIAID NIH HHS/United States Wellcome Trust/United Kingdom Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't United States Clinical infectious diseases : an official publication of the Infectious Diseases Society of America Nihms208805 Clin Infect Dis. 2010 Aug 15;51(4):401-8. PY - 2010 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1537-6591 (Electronic) 1058-4838 (Linking) SP - 401-8 ST - Tuberculosis transmission to young children in a South African community: modeling household and community infection risks T2 - Clin Infect Dis TI - Tuberculosis transmission to young children in a South African community: modeling household and community infection risks UR - http://cid.oxfordjournals.org/content/51/4/401.full.pdf VL - 51 ID - 2605 ER - TY - JOUR AB - BACKGROUND: Hong Kong is an affluent subtropical city with a well-developed healthcare infrastructure but an intermediate TB burden. Declines in notification rates through the 1960s and 1970s have slowed since the 1980s to the current level of around 82 cases per 100 000 population. We studied the transmission dynamics of TB in Hong Kong to explore the factors underlying recent trends in incidence. METHODOLOGY/PRINCIPAL FINDINGS: We fitted an age-structured compartmental model to TB notifications in Hong Kong between 1968 and 2008. We used the model to quantify the proportion of annual cases due to recent transmission versus endogenous reactivation of latent infection, and to project trends in incidence rates to 2018. The proportion of annual TB notifications attributed to endogenous reactivation increased from 46% to 70% between 1968 and 2008. Age-standardized notification rates were projected to decline to approximately 56 per 100 000 in 2018. CONCLUSIONS/SIGNIFICANCE: Continued intermediate incidence of TB in Hong Kong is driven primarily by endogenous reactivation of latent infections. Public health interventions which focus on reducing transmission may not lead to substantial reductions in disease burden associated with endogenous reactivation of latent infections in the short- to medium-term. While reductions in transmission with socio-economic development and public health interventions will lead to declines in TB incidence in these regions, a high prevalence of latent infections may hinder substantial declines in burden in the longer term. These findings may therefore have important implications for the burden of TB in developing regions with higher levels of transmission currently. AD - Department of Community Medicine and School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China. AN - 20454620 AU - Wu, P. AU - Lau, E. H. AU - Cowling, B. J. AU - Leung, C. C. AU - Tam, C. M. AU - Leung, G. M. DO - 10.1371/journal.pone.0010468 ET - 05/11 LA - eng N1 - Wu, Peng Lau, Eric H Y Cowling, Benjamin J Leung, Chi-Chiu Tam, Cheuk-Ming Leung, Gabriel M 1 U54 GM088558/GM/NIGMS NIH HHS/United States Research Support, N.I.H., Extramural United States PloS one PLoS One. 2010 May 3;5(5):e10468. PY - 2010 RN - fulltext fulltext_1208 SN - 1932-6203 (Electronic) 1932-6203 (Linking) SP - e10468 ST - The transmission dynamics of tuberculosis in a recently developed chinese city T2 - PLoS One TI - The transmission dynamics of tuberculosis in a recently developed chinese city UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=20454620http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2862741/pdf/pone.0010468.pdf VL - 5 ID - 2606 ER - TY - JOUR AU - Yang, H. M. AU - Raimundo, S. M. DO - doi:10.1186/1742-4682-7-41 ET - 8 November PY - 2010 RN - fulltext fulltext_1208 ST - Assessing the effects of multiple infections and long latency in the dynamics of tuberculosis T2 - Theoretical Biology and Medical Modelling TI - Assessing the effects of multiple infections and long latency in the dynamics of tuberculosis UR - http://www.tbiomed.com/content/pdf/1742-4682-7-41.pdf VL - 7 ID - 2607 ER - TY - JOUR AB - Two tuberculosis (TB) models with incomplete treatment are investigated. It is assumed that the treated individuals may enter either the latent compartment due to the remainder of Mycobacterium tuberculosis or the infectious compartment due to the treatment failure. The first model is a simple one with treatment failure reflecting the current TB treatment fact in most countries with high tuberculosis incidence. The second model refines the simple one by dividing the latent compartment into slow and fast two kinds of progresses. This improvement can be used to describe the case that the latent TB individuals have been infected with some other chronic diseases (such as HIV and diabetes) which may weaken the immunity of infected individuals and shorten the latent period of TB. Both of the two models assume mass action incidence and exponential distributions of transfers between different compartments. The basic reproduction numbers of the two models are derived and their intuitive epidemiological interpretations are given. The global dynamics of two models are all proved by using Liapunov functions. At last, some strategies to control the spread of tuberculosis are discussed. (C) 2010 Elsevier Ltd. All rights reserved. AD - Xi An Jiao Tong Univ, Dept Appl Math, Xian 710049, Peoples R China AF Engn Univ, Dept Appl Math & Phys, Xian 710051, Peoples R China Henan Univ Sci & Technol, Dept Math, Luoyang 471003, Peoples R China AN - WOS:000285445800010 AU - Yang, Y. L. AU - Li, J. Q. AU - Ma, Z. E. AU - Liu, L. J. DA - Jan-Dec DO - 10.1016/j.chaos.2010.09.002 IS - 1-12 J2 - Chaos Soliton Fract KW - sei epidemic model drug-resistance transmission reinfection dynamics LA - English N1 - 696mp Times Cited:9 Cited References Count:23 PY - 2010 SN - 0960-0779 SP - 79-85 ST - Global stability of two models with incomplete treatment for tuberculosis T2 - Chaos Solitons & Fractals TI - Global stability of two models with incomplete treatment for tuberculosis UR - ://WOS:000285445800010 VL - 43 ID - 4868 ER - TY - BOOK A2 - Jiang, Y. A2 - Song, Q. K. A2 - Chen, L. S. A2 - Tan, Y. S. AB - A tuberculosis model with incomplete treatment is investigated. It is assumed that the treated individuals may enter the susceptible compartment due to complete treatment, or enter the latent compartment due to the existence of tubercle bacillus for incomplete treatment, even enter the infectious compartment due to the failure of treatment. The basic reproduction number is obtained, and it has been shown that the dynamics of the model is determined by its basic reproduction number. If the basic reproduction number is less than or equal to one, there exists only the disease-free equilibrium which is globally asymptotically stable, and the disease dies cut eventually. If the basic reproduction number is greater than one, besides the unstable disease-free equilibrium, there exists a unique endemic equilibrium, and the disease is uniformly persistent. AD - [Yang, Yali] Xi An Jiao Tong Univ, Dept Appl Math, Xian 710049, Peoples R China. Yang, YL (reprint author), Xi An Jiao Tong Univ, Dept Appl Math, Xian 710049, Peoples R China. yylhgr@126.com AN - WOS:000280408600083 AU - Yang, Y. L. AU - Li, J. Q. AU - Yang, Y. S. CY - Liverpool KW - tuberculosis treatment equilibrium global stability uniform persistence LA - English N1 - ISI Document Delivery No.: BPZ09 Times Cited: 0 Cited Reference Count: 10 Yang, Yali Li, Jianquan Yang, Youshe Proceedings Paper 7th Conference on Biological Dynamic System and Stability of Differential Equation May 14-16, 2010 Chongqing, PEOPLES R CHINA 113, academic house, mill lane, wavertree technology park, liverpool, l13 4 ah, england PB - World Acad Union-World Acad Press PY - 2010 SN - 978-1-84626-029-2 SP - 397-400 ST - Qualitative Analysis of A Tuberculosis Model with Incomplete Treatment T2 - Proceedings of the 7th Conference on Biological Dynamic System and Stability of Differential Equation, Vols I and Ii TI - Qualitative Analysis of A Tuberculosis Model with Incomplete Treatment UR - ://WOS:000280408600083 ID - 5875 ER - TY - CHAP A2 - Sivaloganathan, S. AB - Tuberculosis (TB) is a contagious disease. It has been a leading cause of death throughout the world. TB has kept being a focus of public health and epidemiological modeling. Based on the fact that most epidemiological data is compiled in certain time interval, discrete TB transmission models are formulated and studied. The basic reproductive number is defined to investigate the dynamical behavior under simple assumptions. The global stability condition of the disease free equilibrium is obtained. The existence of the endemic equilibrium is established. The existence of the periodic solution and the stability of the endemic equilibrium are investigated numerically. The discrete TB model with time dependent model is used to describe the seasonal fluctuation of the monthly reported TB cases in China. The discrete TB model with immigration is applied to simulate the impact of immigration to TB infection in Canada. AD - [Zhou, Yicang; Cao, Hui] Xi An Jiao Tong Univ, Dept Math, Sch Sci, Xian 710049, Peoples R China. Zhou, YC (reprint author), Xi An Jiao Tong Univ, Dept Math, Sch Sci, Xian 710049, Peoples R China. zhouyc@mail.xjtu.edu.cn; caohui0103@163.com AN - WOS:000289584200005 AU - Zhou, Y. C. AU - Cao, H. CY - Providence KW - infectious-diseases epidemic model health system china LA - English N1 - ISI Document Delivery No.: BUK19 Times Cited: 5 Cited Reference Count: 36 Zhou, Yicang Cao, Hui Proceedings Paper Society-for-Mathematical-Biology Conference Jul 29-aug 02, 2008 Toronto, CANADA Fields Inst, Pacif Inst Math Sci, Natl Sci Fdn China, Soc Math Biol P.o. box 6248, providence, ri 02940 usa 1069-5265 PB - Amer Mathematical Soc PY - 2010 SN - 978-0-8218-4845-6 SP - 83-112 ST - Discrete Tuberculosis Models and Their Application T2 - New Perspectives in Mathematical Biology T3 - Fields Institute Communications TI - Discrete Tuberculosis Models and Their Application UR - ://WOS:000289584200005 VL - 57 ID - 5874 ER - TY - JOUR AB - BACKGROUND: Detailed analysis of the dynamic interactions among biological, environmental, social, and economic factors that favour the spread of certain diseases is extremely useful for designing effective control strategies. Diseases like tuberculosis that kills somebody every 15 seconds in the world, require methods that take into account the disease dynamics to design truly efficient control and surveillance strategies. The usual and well established statistical approaches provide insights into the cause-effect relationships that favour disease transmission but they only estimate risk areas, spatial or temporal trends. Here we introduce a novel approach that allows figuring out the dynamical behaviour of the disease spreading. This information can subsequently be used to validate mathematical models of the dissemination process from which the underlying mechanisms that are responsible for this spreading could be inferred. METHODOLOGY/PRINCIPAL FINDINGS: The method presented here is based on the analysis of the spread of tuberculosis in a Brazilian endemic city during five consecutive years. The detailed analysis of the spatio-temporal correlation of the yearly geo-referenced data, using different characteristic times of the disease evolution, allowed us to trace the temporal path of the aetiological agent, to locate the sources of infection, and to characterize the dynamics of disease spreading. Consequently, the method also allowed for the identification of socio-economic factors that influence the process. CONCLUSIONS/SIGNIFICANCE: The information obtained can contribute to more effective budget allocation, drug distribution and recruitment of human skilled resources, as well as guiding the design of vaccination programs. We propose that this novel strategy can also be applied to the evaluation of other diseases as well as other social processes. AD - Departamento de Fisica, Universidade Federal de Pernambuco, Cidade Universitaria, Recife, Pernambuco, Brazil. rita.zorzenon@gmail.com AN - 21152440 AU - Zorzenon dos Santos, R. M. AU - Amador, A. AU - de Souza, W. V. AU - de Albuquerque, M. F. AU - Ponce Dawson, S. AU - Ruffino-Netto, A. AU - Zarate-Blades, C. R. AU - Silva, C. L. DO - 10.1371/journal.pone.0014140 [doi] DP - Nlm ET - 12/15 KW - Brazil/epidemiology Geography Humans Incidence Population Density Population Dynamics Population Surveillance/ methods Socioeconomic Factors Tuberculosis/epidemiology/ prevention & control/ transmission LA - eng N1 - Zorzenon dos Santos, Rita M Amador, Ana de Souza, Wayner V de Albuquerque, Maria Fatima P M Ponce Dawson, Silvina Ruffino-Netto, Antonio Zarate-Blades, Carlos R Silva, Celio L Research Support, Non-U.S. Gov't United States PloS one PLoS One. 2010 Nov 30;5(11):e14140. PY - 2010 RN - fulltext fulltext_1208 SN - 1932-6203 (Electronic) 1932-6203 (Linking) SP - e14140 ST - A dynamic analysis of tuberculosis dissemination to improve control and surveillance T2 - PLoS One TI - A dynamic analysis of tuberculosis dissemination to improve control and surveillance UR - http://www.plosone.org/article/fetchObjectAttachment.action?uri=info%3Adoi%2F10.1371%2Fjournal.pone.0014140&representation=PDF VL - 5 ID - 2608 ER - TY - JOUR AB - A model is built and used to explore the effects of variations in transmission and/or progression on the decline of tuberculosis rates during the twentieth century. This study also makes use of available data generated over two significantly distinct spatial scales: one (global) involving the United States and the second (local) utilizing the tuberculosis data generated by the state of Massachusetts. AD - [Pablo Aparicio, Juan] Univ Nacl Salta, CONICET, Inst Invest Energias Convenc, Salta, Argentina. [Castillo-Chavez, Carlos] Santa Fe Inst, Santa Fe, NM 87501 USA. [Castillo-Chavez, Carlos] Arizona State Univ, Tempe, AZ 85287 USA. Aparicio, JP (reprint author), Univ Nacl Salta, CONICET, Inst Invest Energias Convenc, Salta, Argentina. juan.p.aparicio@gmail.com; cchavez@asu.edu AN - WOS:000337352200006 AU - Aparicio, J. P. AU - Castillo-Chavez, C. KW - brief epidemiologic history disease arcana transmission Mathematical & Computational Biology LA - English M3 - Proceedings Paper N1 - ISI Document Delivery No.: BA7BE Times Cited: 0 Cited Reference Count: 38 Pablo Aparicio, Juan Castillo-Chavez, Carlos Mondaini, RP 1st International Symposium on Mathematical and Computational Biology of the Society-for-Mathematical-Biology Jul 24-29, 2010 Rio de Janeiro, BRAZIL Soc Math Biol, Coordinat Improvement Higher Educ Personell Agcy, Board Trustees, Natl Res Council Sci & Technol Dev Agcy, Board Trustees, Fdn Res Support Rio de Janeiro State Agcy, Board Trustees National Science Foundation [NSF - DMS -0502349]; National Security Agency [NSA - H98230- 06-1-0097] JPA is a member of the CONICET.This project have been partially sup- ported by grants from the National Science Foundation (NSF - Grant DMS -0502349), the National Security Agency (NSA - Grant H98230- 06-1-0097), the Alfred T. Sloan Foundation and the Office of the Provost of Arizona State University. 0 1 World scientific publ co pte ltd Singapore 978-981-4343-42-8 PY - 2011 SP - 73-95 ST - ON THE USE OF MECHANISTIC AND DATA-DRIVEN MODELS IN POPULATION DYNAMICS: THE CASE OF TUBERCULOSIS IN THE US OVER THAT PAST TWO CENTURIES T2 - Biomat 2010: International Symposium on Mathematical and Computational Biology TI - ON THE USE OF MECHANISTIC AND DATA-DRIVEN MODELS IN POPULATION DYNAMICS: THE CASE OF TUBERCULOSIS IN THE US OVER THAT PAST TWO CENTURIES UR - ://WOS:000337352200006 ID - 5782 ER - TY - JOUR AB - OBJECTIVES: Almost 20% of people smoke tobacco worldwide--a percentage projected to rise in many poor countries. Smoking has been linked to increased individual risk of tuberculosis infection and mortality, but it remains unclear how these risks affect population-wide tuberculosis rates. DESIGN: We constructed a state transition, compartmental, mathematical model of tuberculosis epidemics to estimate the impact of alternative future smoking trends on tuberculosis control. We projected tuberculosis incidence, prevalence, and mortality in each World Health Organization region from 2010 to 2050, and incorporated changing trends in smoking, case detection, treatment success, and HIV prevalence. RESULTS: The model predicted that smoking would produce an excess of 18 million tuberculosis cases (standard error 16-20) and 40 million deaths from tuberculosis (39-41) between 2010 and 2050, if smoking trends continued along current trajectories. The effect of smoking was anticipated to increase the number of tuberculosis cases by 7% (274 million v 256 million) and deaths by 66% (101 million v 61 million), compared with model predictions that did not account for smoking. Smoking was also expected to delay the millennium development goal target to reduce tuberculosis mortality by half from 1990 to 2015. The model estimated that aggressive tobacco control (achieving a 1% decrease in smoking prevalence per year down to eradication) would avert 27 million smoking attributable deaths from tuberculosis by 2050. However, if the prevalence of smoking increased to 50% of adults (as observed in countries with high tobacco use), the model estimated that 34 million additional deaths from tuberculosis would occur by 2050. CONCLUSIONS: Tobacco smoking could substantially increase tuberculosis cases and deaths worldwide in coming years, undermining progress towards tuberculosis mortality targets. Aggressive tobacco control could avert millions of deaths from tuberculosis. AD - Department of Medicine, University of California San Francisco, San Francisco, CA 94143, USA. sanjay.basu@ucsf.edu AN - 21972295 AU - Basu, S. AU - Stuckler, D. AU - Bitton, A. AU - Glantz, S. A. DO - 10.1136/bmj.d5506. DP - Nlm ET - 10/06 KW - Adult Humans Models, Theoretical Prevalence Smoking/ adverse effects/epidemiology/prevention & control Tuberculosis/ epidemiology/mortality LA - eng PY - 2011 RN - fulltext fulltext_1208 SN - 1756-1833 (Electronic) 0959-535X (Linking) SP - d5506 ST - Projected effects of tobacco smoking on worldwide tuberculosis control: mathematical modelling analysis T2 - BMJ TI - Projected effects of tobacco smoking on worldwide tuberculosis control: mathematical modelling analysis UR - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3186817/pdf/bmj.d5506.pdf VL - 343 ID - 2609 ER - TY - JOUR AB - Tuberculosis outbreaks originating in prisons, mines, or hospital wards can spread to the larger community. Recent proposals have targeted these high-transmission institutional amplifiers by improving case detection, treatment, or reducing the size of the exposed population. However, what effects these alternative proposals may have is unclear. We mathematically modeled these control strategies and found case detection and treatment methods insufficient in addressing epidemics involving common types of institutional amplifiers. Movement of persons in and out of amplifiers fundamentally altered the transmission dynamics of tuberculosis in a manner not effectively mitigated by detection or treatment alone. Policies increasing the population size exposed to amplifiers or the per-person duration of exposure within amplifiers potentially worsened incidence, even in settings with high rates of detection and treatment success. However, reducing the total population size entering institutional amplifiers significantly lowered tuberculosis incidence and the risk of propagating new drug-resistant tuberculosis strains. AD - Department of Medicine, University of California, Division of General Internal Medicine, San Francisco General Hospital, San Francisco, California 94143, USA. sanjay.basu@ucsf.edu AN - 21212197 AU - Basu, S. AU - Stuckler, D. AU - McKee, M. DA - Jan DO - 84/1/30 [pii] 10.4269/ajtmh.2011.10-0472 [doi] DP - Nlm ET - 01/08 KW - Africa/epidemiology Algorithms Communicable Disease Control/ methods Computer Simulation Epidemics/ prevention & control Europe/epidemiology Hospitals Humans Mining Models, Theoretical Prisons Tuberculosis/ epidemiology/prevention & control L1 - internal-pdf://1595374355/Basu-2011-Addressing institutional amplifiers.pdf LA - eng N1 - Basu, Sanjay Stuckler, David McKee, Martin Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. United States The American journal of tropical medicine and hygiene Am J Trop Med Hyg. 2011 Jan;84(1):30-7. PY - 2011 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1476-1645 (Electronic) 0002-9637 (Linking) SP - 30-7 ST - Addressing institutional amplifiers in the dynamics and control of tuberculosis epidemics T2 - Am J Trop Med Hyg TI - Addressing institutional amplifiers in the dynamics and control of tuberculosis epidemics UR - http://www.ajtmh.org/content/84/1/30.full.pdf https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3005502/pdf/tropmed-84-030.pdf VL - 84 ID - 2610 ER - TY - JOUR AB - Complex biological systems exhibit a property of robustness at all levels of organization. Through different mechanisms, the system tries to sustain stress such as due to starvation or drug exposure. To explore whether reconfiguration of the metabolic networks is used as a means to achieve robustness, we have studied possible metabolic adjustments in Mtb upon exposure to isoniazid (INH), a front-line clinical drug. The redundancy in the genome of M. tuberculosis (Mtb) makes it an attractive system to explore if alternate routes of metabolism exist in the bacterium. While the mechanism of action of INH is well studied, its effect on the overall metabolism is not well characterized. Using flux balance analysis, inhibiting the fluxes flowing through the reactions catalyzed by Rv1484, the target of INH, significantly changes the overall flux profiles. At the pathway level, activation or inactivation of certain pathways distant from the target pathway, are seen. Metabolites such as NADPH are shown to reduce drastically, while fatty acids tend to accumulate. The overall biomass also decreases with increasing inhibition levels. Inhibition studies, pathway level clustering and comparison of the flux profiles with the gene expression data indicate the activation of folate metabolism, ubiquinone metabolism, and metabolism of certain amino acids. This analysis provides insights useful for target identification and designing strategies for combination therapy. Insights gained about the role of individual components of a system and their interactions will also provide a basis for reconstruction of whole systems through synthetic biology approaches. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11693-011-9075-6) contains supplementary material, which is available to authorized users. AD - Bioinformatics Centre, Indian Institute of Science, Bangalore, India. AN - 22132057 AU - Bhat, A. G. AU - Vashisht, R. AU - Chandra, N. DA - Dec DO - 10.1007/s11693-011-9075-6 [doi] 9075 [pii] DP - Nlm ET - 12/02 LA - eng N1 - Bhat, Ashwini G Vashisht, Rohit Chandra, Nagasuma Germany Systems and synthetic biology Syst Synth Biol. 2010 Dec;4(4):299-309. Epub 2011 Feb 26. PY - 2011 RN - fulltext fulltext_1208 SN - 1872-5333 (Electronic) 1872-5325 (Linking) SP - 299-309 ST - Modeling metabolic adjustment in Mycobacterium tuberculosis upon treatment with isoniazid T2 - Syst Synth Biol TI - Modeling metabolic adjustment in Mycobacterium tuberculosis upon treatment with isoniazid UR - http://www.springerlink.com/content/965qr26w05854550/ VL - 4 ID - 2586 ER - TY - JOUR AB - In recent years, bacteria have become resistant to antibiotics, leading to a decline in the effectiveness of antibiotics in treating infectious diseases. A mathematical model for multi-strain tuberculosis transmission dynamics to assess the burden of drug-sensitive, multidrug-resistant and extensively drug-resistant tuberculosis is formulated and analyzed. Each single strain submodel is shown to exhibit backward bifurcation when the threshold parameter is less than unity. Both analytical and numerical results show that resistance to drugs increase with increase in drug use, that is, active tuberculosis treatment results in a reduction of drug sensitive and increase in multidrug-resistant tuberculosis. Furthermore, use of second line drugs results in a decrease of the multidrug-resistant and increase of extensively drug resistant tuberculosis as most cases of multidrug resistant tuberculosis occur as a result of inappropriate, misuse or mismanaged treatment. Both the analytic results and numerical simulations suggest that quarantine of extensively drug resistant TB cases in addition to treatment of other forms of TB may be able to reduce the spread of the epidemic in poor resource-settings. (C) 2011 Elsevier Inc. All rights reserved. AD - Natl Univ Sci & Technol, Dept Appl Math, Modelling Biomed Syst Res Grp, Ascot, Bulawayo, Zimbabwe Univ Cambridge, Dept Vet Med, Cambridge CB3 0ES, England AN - WOS:000291407800044 AU - Bhunu, C. P. DA - Sep DO - 10.1016/j.apm.2011.03.037 IS - 9 J2 - Appl Math Model KW - multidrug-resistant tuberculosis extensively drug-resistant tuberculosis first line tuberculosis drugs second line tuberculosis drugs drug-resistant tuberculosis mycobacterium-tuberculosis exogenous reinfection south-africa emergence equilibria epidemics dynamics disease tb L1 - internal-pdf://0952434647/Bhunu 2011.pdf LA - English N1 - 774sw Times Cited:4 Cited References Count:47 PY - 2011 SN - 0307-904x SP - 4647-4660 ST - Mathematical analysis of a three-strain tuberculosis transmission model T2 - Applied Mathematical Modelling TI - Mathematical analysis of a three-strain tuberculosis transmission model UR - ://WOS:000291407800044 VL - 35 ID - 529 ER - TY - JOUR AB - Molecular epidemiologic studies may use genotypic clustering of isolates as an indicator of recent transmission. It has been shown that missing cases lead to underestimating clustering, and modelling studies suggested that they may also lead to underestimating odds ratios for clustering. Using a national, comprehensive database from the Netherlands covering 15 years between 1993 and 2007 and including over 12,000 patients and their isolates, the authors determined the effects of sampling at random, in time, and by geographic area. As expected, sampling reduced the observed clustering percentages. However, sampling did not reduce the observed odds ratios for clustering. The main explanations for this discrepancy with model outcomes were that a substantial proportion of clustered cases were found in large clusters and that risk factors for clustering tended to be-among clustered cases-also risk factors for large clusters. The authors conclude that, in settings where risk factors for clustering may be interpreted as risk factors for recent transmission, these risk factors are also associated with larger cluster sizes. As a result, odds ratios would show limited sampling bias. AD - Department of Clinical Epidemiology, Biostatistics, and Bioinformatics, Academic Medical Center, University of Amsterdam, the Netherlands. mborgdorff@ggd.amsterdam.nl AN - 21606233 AU - Borgdorff, M. W. AU - van den Hof, S. AU - Kalisvaart, N. AU - Kremer, K. AU - van Soolingen, D. DA - Jul 15 DO - kwr061 [pii] 10.1093/aje/kwr061 [doi] DP - Nlm ET - 05/25 KW - Adolescent Adult Child Cluster Analysis Female Humans Male Molecular Epidemiology Odds Ratio Risk Factors Sampling Studies Tuberculosis/ epidemiology LA - eng N1 - Borgdorff, Martien W van den Hof, Susan Kalisvaart, Nico Kremer, Kristin van Soolingen, Dick United States American journal of epidemiology Am J Epidemiol. 2011 Jul 15;174(2):243-51. Epub 2011 May 23. PY - 2011 RN - fulltext fulltext_1208 SN - 1476-6256 (Electronic) 0002-9262 (Linking) SP - 243-51 ST - Influence of sampling on clustering and associations with risk factors in the molecular epidemiology of tuberculosis T2 - Am J Epidemiol TI - Influence of sampling on clustering and associations with risk factors in the molecular epidemiology of tuberculosis UR - http://aje.oxfordjournals.org/content/174/2/243.full.pdf VL - 174 ID - 2612 ER - TY - JOUR AB - This paper deals with the problem of modeling and parameter estimation of a deterministic model of tuberculosis (abbreviated as TB for tubercle bacillus). We first propose and analyze a tuberculosis model without seasonality that incorporates the essential biological and epidemiological features of the disease. The model is shown to exhibit the phenomenon of backward bifurcation, where a stable disease-free equilibrium coexists with one or more stable endemic equilibria when the associated basic reproduction number is less than unity. The statistical data of new TB cases show seasonal fluctuations in many countries. Then, we extend the proposed TB model by incorporating seasonality. We propose a numerical study to estimate unknown parameters according to demographic and epidemiological data in Cameroon. Simulation results are in good accordance with the seasonal variation of the reported new cases of active TB in Cameroon. AD - Univ Douala, Fac Sci, Dept Math & Comp Sci, Lab Appl Math, Douala, Cameroon Postdam Inst Climate Impact Res PIK, D-14412 Potsdam, Germany Humboldt Univ, Dept Phys, D-12489 Berlin, Germany UPMC UMMISCO, UMI IRD 209, Project MASAIE INRIA Grand Est, Bondy, France LIRIMA, Project GRIMCAPE LIRIMA, Yaounde, Cameroon AN - WOS:000294467900014 AU - Bowong, S. AU - Kurths, J. DA - Jul DO - 10.1142/S0218127411029598 IS - 7 J2 - Int J Bifurcat Chaos KW - dynamical systems epidemiological models tuberculosis season pattern parameter estimation heterogeneous populations seasonality bifurcations diseases dynamics LA - English N1 - 814pa Times Cited:1 Cited References Count:36 PY - 2011 SN - 0218-1274 SP - 1999-2015 ST - Modeling and Parameter Estimation of Tuberculosis with Application to Cameroon T2 - International Journal of Bifurcation and Chaos TI - Modeling and Parameter Estimation of Tuberculosis with Application to Cameroon UR - ://WOS:000294467900014 VL - 21 ID - 4873 ER - TY - JOUR AB - Background. Tuberculosis (TB) often occurs among household contacts of people with active TB. It is unclear whether clustering of cases represents household transmission or shared household risk factors for TB. Methods. We used cross-sectional data from 764 households in Lima, Peru, to estimate the relative contributions of household and community transmission, the average time between cases, and the immunity afforded by a previous TB infection. Results. The distribution of cases per household suggests that almost 7 of 10 nonindex household cases were infected in the community rather than in the household. The average interval between household cases was 3.5 years. We observed a saturation effect in the number of cases per household and estimated that protective immunity conferred up to 35% reduction in the risk of disease. Conclusions. Cross-sectional household data can elucidate the natural history and transmission dynamics of TB. In this high-incidence setting, we found that the majority of cases were attributable to community transmission and that household contacts of case patients derive some immunity from household exposures. Screening of household contacts may be an effective method of detecting new TB cases if carried out over several years. AD - Department of Epidemiology, Harvard School of Public Health. AN - 21592987 AU - Brooks-Pollock, E. AU - Becerra, M. C. AU - Goldstein, E. AU - Cohen, T. AU - Murray, M. B. DO - jir162 [pii] 10.1093/infdis/jir162 LA - eng N1 - Brooks-Pollock, Ellen Becerra, Mercedes C Goldstein, Edward Cohen, Ted Murray, Megan B United States The Journal of infectious diseases J Infect Dis. 2011 Jun;203(11):1582-9. PY - 2011 RN - fulltext fulltext_1208 SN - 1537-6613 (Electronic) 0022-1899 (Linking) SP - 1582-1589 ST - Epidemiologic inference from the distribution of tuberculosis cases in households in Lima, Peru T2 - Journal of Infectious Diseases TI - Epidemiologic inference from the distribution of tuberculosis cases in households in Lima, Peru UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=21592987http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3096792/pdf/jir162.pdf VL - 203 ID - 2613 ER - TY - CHAP A2 - Ran, C. A2 - Yang, G. AB - The research will analyze the complex dynamic mathematic model of tuberculosis epidemic and determine its stability property by using the popular Matlab/Simulink software and relative software packages. Facing to the currently TB epidemic situation, in this project we will investgate the development of TB and its developing trend throught constructing the dynamic biomathematics system model of TB. (C) 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of [CEIS 2011] AD - [Chung, Chun-Yen; Chung, Hung-Yuan] Natl Cent Univ, Dept Elect Engn, Jhongli 32001, Taoyuan County, Taiwan. [Ou, Shih-Ching] Univ Kang Ning, Dept Digital Applicat, Tainan 709, Taiwan. Chung, CY (reprint author), Natl Cent Univ, Dept Elect Engn, Jhongli 32001, Taoyuan County, Taiwan. chunyen911@gmail.com AN - WOS:000300876503125 AU - Chung, C. Y. AU - Chung, H. Y. AU - Ou, S. C. CY - Amsterdam DO - 10.1016/j.proeng.2011.08.679 KW - tuberculosis Matlab mathematic intrinsic transmission dynamics LA - English N1 - ISI Document Delivery No.: BYZ94 Times Cited: 1 Cited Reference Count: 4 Chung, Chun-Yen Chung, Hung-Yuan Ou, Shih-Ching Proceedings Paper International Conference on Advanced in Control Engineering and Information Science (CEIS) Aug 18-19, 2011 Dali, PEOPLES R CHINA Chung, Hung-Yuan/H-8055-2012 Chung, Hung-Yuan/0000-0002-1787-173X Sara burgerhartstraat 25, po box 211, 1000 ae amsterdam, netherlands 1877-7058 PB - Elsevier Science Bv PY - 2011 ST - Computer Simulation Applied to a Bio-mathematic Model for Tuberculosis T2 - Ceis 2011 T3 - Procedia Engineering TI - Computer Simulation Applied to a Bio-mathematic Model for Tuberculosis UR - ://WOS:000300876503125 VL - 15 ID - 5772 ER - TY - JOUR AB - The emergence of drug resistance in M. tuberculosis undermines the efficacy of tuberculosis (TB) treatment in individuals and of TB control programs in populations. Multiple drug resistance is often attributed to sequential functional monotherapy, and standard initial treatment regimens have therefore been designed to include simultaneous use of four different antibiotics. Despite the widespread use of combination therapy, highly resistant M. tb strains have emerged in many settings. Here we use a stochastic birth-death model to estimate the probability of the emergence of multidrug resistance during the growth of a population of initially drug sensitive TB bacilli within an infected host. We find that the probability of the emergence of resistance to the two principal anti-TB drugs before initiation of therapy ranges from 10(-5) to 10(-4); while rare, this is several orders of magnitude higher than previous estimates. This finding suggests that multidrug resistant M. tb may not be an entirely "man-made" phenomenon and may help explain how highly drug resistant forms of TB have independently emerged in many settings. AD - Department of Engineering Mathematics, University of Bristol, Bristol, United Kingdom. AN - 21479171 AU - Colijn, C. AU - Cohen, T. AU - Ganesh, A. AU - Murray, M. DO - 10.1371/journal.pone.0018327 [doi] DP - Nlm ET - 04/12 KW - Humans Isoniazid/pharmacology/therapeutic use Probability Time Factors Tuberculosis, Multidrug-Resistant/diagnosis/ drug therapy L1 - internal-pdf://3240893575/Colijn-2011-Spontaneous emergence of multiple.pdf LA - eng N1 - Colijn, Caroline Cohen, Ted Ganesh, Ayalvadi Murray, Megan DP2 OD006663-01/OD/NIH HHS/United States DP2OD006663/OD/NIH HHS/United States U19AI076217/AI/NIAID NIH HHS/United States Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't United States PloS one PLoS One. 2011 Mar 30;6(3):e18327. PY - 2011 RN - fulltext fulltext_1208 SN - 1932-6203 (Electronic) 1932-6203 (Linking) SP - e18327 ST - Spontaneous emergence of multiple drug resistance in tuberculosis before and during therapy T2 - PLoS One TI - Spontaneous emergence of multiple drug resistance in tuberculosis before and during therapy UR - http://www.plosone.org/article/fetchObjectAttachment.action?uri=info%3Adoi%2F10.1371%2Fjournal.pone.0018327&representation=PDF https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3068161/pdf/pone.0018327.pdf VL - 6 ID - 2615 ER - TY - JOUR AB - Application of molecular dynamics simulation technique has become a conventional computational methodology to calculate significant processes at the molecular level. This computational methodology is particularly useful for analyzing the dynamics of protein-ligand systems. Several uses of molecular dynamics simulation makes possible evaluation of important structural features found at interface between a ligand and a protein, such as intermolecular hydrogen bonds, contact area and binding energy. Considering structure-based virtual screening, molecular dynamics simulations play a pivotal role in understanding the features that are important for ligand-binding affinity. This information could be employed to select higher-affinity ligands obtained in screening processes. Many protein targets such as enoyl-[acyl-carrier-protein] reductase (InhA), purine nucleoside phosphorylase (PNP), and shikimate kinase have been submitted to these simulations and will be analyzed here. All command files used in this review are available for download at http://azevedolab.net/md_75.html. AD - Instituto Nacional de Ciencia e Tecnologia em Tuberculose-CNPq-MCT, Faculdade de Biociencias, Laboratorio de Bioquimica Estrutural, Pontificia Universidade Catolica do Rio Grande do Sul, Porto Alegre - RS, Brazil. walter@azevedolab.net AN - 21366529 AU - de Azevedo, W. F., Jr. DO - BSP/CMC/E-Pub/2011/ 087 [pii] DP - Nlm ET - 03/04 KW - Bacterial Proteins/ chemistry/metabolism Enoyl-(Acyl-Carrier-Protein) Reductase (NADH)/chemistry/metabolism Molecular Dynamics Simulation Mycobacterium tuberculosis/ enzymology/metabolism Phosphotransferases (Alcohol Group Acceptor)/chemistry/metabolism Purine-Nucleoside Phosphorylase/chemistry/metabolism LA - eng N1 - de Azevedo, W F Jr Research Support, Non-U.S. Gov't Review Netherlands Current medicinal chemistry Curr Med Chem. 2011;18(9):1353-66. PY - 2011 RN - fulltext fulltext_1208 SN - 1875-533X (Electronic) 0929-8673 (Linking) SP - 1353-66 ST - Molecular dynamics simulations of protein targets identified in Mycobacterium tuberculosis T2 - Curr Med Chem TI - Molecular dynamics simulations of protein targets identified in Mycobacterium tuberculosis VL - 18 ID - 2616 ER - TY - JOUR AB - In this work we propose an alternative model of the spread of tuberculosis (TB) and the emergence of drug resistance due to the treatment with antibiotics. We implement the simulations by an agent-based model computational approach where the spatial structure is taken into account. The spread of tuberculosis occurs according to probabilities defined by the interactions among individuals. The model was validated by reproducing results already known from the literature in which different treatment regimes yield the emergence of drug resistance. The different patterns of TB spread can be visualized at any time of the system evolution. The implementation details as well as some results of this alternative approach are discussed. AD - Univ Fed Fluminense, Dept Fis, Inst Ciencias Exatas ICEx, BR-27213350 Rio De Janeiro, Brazil Univ Guelph, Dept Math & Stat, Guelph, ON N1G 2W1, Canada Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Pret, BR-14040901 Sao Paulo, Brazil Natl Inst Sci & Technol Complex Syst, BR-14040901 Sao Paulo, Brazil AN - WOS:000292190200004 AU - de Espindola, A. L. AU - Bauch, C. T. AU - Cabella, B. C. T. AU - Martinez, A. S. DA - May DO - Artn P05003 10.1088/1742-5468/2011/05/P05003 J2 - J Stat Mech-Theory E KW - population dynamics (theory) epidemic modelling control strategies resistance epidemics LA - English N1 - 784ww Times Cited:5 Cited References Count:20 PY - 2011 SN - 1742-5468 ST - An agent-based computational model of the spread of tuberculosis T2 - Journal of Statistical Mechanics-Theory and Experiment TI - An agent-based computational model of the spread of tuberculosis UR - ://WOS:000292190200004 http://iopscience.iop.org/article/10.1088/1742-5468/2011/05/P05003/meta ID - 4874 ER - TY - JOUR AU - Dodd, Peter J. AU - White, Richard G. AU - Corbett, Elizabeth L. DO - 10.1371/journal.pone.0029130 IS - 12 L1 - file:///C:/Users/James/AppData/Local/Mendeley Ltd./Mendeley Desktop/Downloaded/Dodd, White, Corbett - 2011 - Periodic Active Case Finding for TB When to Look.pdf internal-pdf://0401618573/Dodd-2011-Periodic Active Case Finding for TB_.pdf PY - 2011 SP - e29130-e29130 ST - Periodic Active Case Finding for TB: When to Look? T2 - PLoS ONE TI - Periodic Active Case Finding for TB: When to Look? UR - http://dx.plos.org/10.1371/journal.pone.0029130 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3245256/pdf/pone.0029130.pdf VL - 6 ID - 3195 ER - TY - JOUR AB - BACKGROUND: Undiagnosed and misdiagnosed tuberculosis (TB) drives the epidemic in India. Serological (antibody detection) TB tests are not recommended by any agency, but widely used in many countries, including the Indian private sector. The cost and impact of using serology compared with other diagnostic techniques is unknown. METHODS AND FINDINGS: Taking a patient cohort conservatively equal to the annual number of serological tests done in India (1.5 million adults suspected of having active TB), we used decision analysis to estimate costs and effectiveness of sputum smear microscopy (US$3.62 for two smears), microscopy plus automated liquid culture (mycobacterium growth indicator tube [MGIT], US$20/test), and serological testing (anda-tb ELISA, US$20/test). Data on test accuracy and costs were obtained from published literature. We adopted the perspective of the Indian TB control sector and an analysis frame of 1 year. Our primary outcome was the incremental cost per disability-adjusted life year (DALY) averted. We performed one-way sensitivity analysis on all model parameters, with multiway sensitivity analysis on variables to which the model was most sensitive. If used instead of sputum microscopy, serology generated an estimated 14,000 more TB diagnoses, but also 121,000 more false-positive diagnoses, 102,000 fewer DALYs averted, and 32,000 more secondary TB cases than microscopy, at approximately four times the incremental cost (US$47.5 million versus US$11.9 million). When added to high-quality sputum smears, MGIT culture was estimated to avert 130,000 incremental DALYs at an incremental cost of US$213 per DALY averted. Serology was dominated by (i.e., more costly and less effective than) MGIT culture and remained less economically favorable than sputum smear or TB culture in one-way and multiway sensitivity analyses. CONCLUSIONS: In India, sputum smear microscopy remains the most cost-effective diagnostic test available for active TB; efforts to increase access to quality-assured microscopy should take priority. In areas where high-quality microscopy exists and resources are sufficient, MGIT culture is more cost-effective than serology as an additional diagnostic test for TB. These data informed a recently published World Health Organization policy statement against serological tests. AD - Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America. AN - 21857810 AU - Dowdy, D. W. AU - Steingart, K. R. AU - Pai, M. DA - Aug DO - 10.1371/journal.pmed.1001074 ET - 08/23 J2 - PLoS medicine KW - Adult Antibodies, Bacterial/*blood Bacteriological Techniques/*economics Bias (Epidemiology) Cost-Benefit Analysis Decision Support Techniques Enzyme-Linked Immunosorbent Assay Humans India Microscopy/economics Mycobacterium/immunology/pathogenicity Sensitivity and Specificity Serologic Tests/*economics Sputum/*microbiology Tuberculosis/*diagnosis/microbiology LA - eng M3 - Comparative Study Research Support, Non-U.S. Gov't N1 - Dowdy, David W Steingart, Karen R Pai, Madhukar Canadian Institutes of Health Research/Canada PLoS Med. 2011 Aug;8(8):e1001074. Epub 2011 Aug 9. PY - 2011 RN - fulltext fulltext_1208 SN - 1549-1676 (Electronic) 1549-1277 (Linking) SP - e1001074 ST - Serological testing versus other strategies for diagnosis of active tuberculosis in India: a cost-effectiveness analysis T2 - PLoS Med TI - Serological testing versus other strategies for diagnosis of active tuberculosis in India: a cost-effectiveness analysis UR - http://www.ncbi.nlm.nih.gov/pubmed/21857810http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3153451/pdf/pmed.1001074.pdf VL - 8 ID - 2618 ER - TY - JOUR AB - PURPOSE: The search for small molecules with activity against Mycobacterium tuberculosis (Mtb) increasingly uses high throughput screening and computational methods. Several public datasets from the Collaborative Drug Discovery Tuberculosis (CDD TB) database have been evaluated with cheminformatics approaches to validate their utility and suggest compounds for testing. METHODS: Previously reported Bayesian classification models were used to predict a set of 283 Novartis compounds tested against Mtb (containing aerobic and anaerobic hits) and to search FDA approved drugs. The Novartis compounds were also filtered with computational SMARTS alerts to identify potentially undesirable substructures. RESULTS: Using the Novartis compounds as a test set for the Bayesian models demonstrated a >4.0-fold enrichment over random screening for finding aerobic hits not in the computational models (N = 34). A 10-fold enrichment was observed for finding Mtb active compounds in the FDA drugs database. 85.9% of the Novartis compounds failed the Abbott SMARTS alerts, a value substantially higher than for known TB drugs. Higher levels of failures of SMARTS filters from different groups also correlate with the number of Lipinski violations. CONCLUSIONS: These computational approaches may assist in finding desirable leads for Tuberculosis drug discovery. AD - Collaborative Drug Discovery, 1633 Bayshore Highway, Suite 342, Burlingame, California 94010, USA. sekins@collaborativedrug.com AN - 21547522 AU - Ekins, S. AU - Freundlich, J. S. DA - Aug DO - 10.1007/s11095-011-0413-x [doi] DP - Nlm ET - 05/07 KW - Antitubercular Agents/chemistry/ pharmacology Bayes Theorem Computer Simulation Databases, Factual Drug Discovery/methods Models, Biological Mycobacterium tuberculosis/drug effects Small Molecule Libraries/chemistry/ pharmacology Tuberculosis/ drug therapy LA - eng N1 - Ekins, Sean Freundlich, Joel S United States Pharmaceutical research Pharm Res. 2011 Aug;28(8):1859-69. Epub 2011 Mar 10. PY - 2011 RN - fulltext fulltext_1208 SN - 1573-904X (Electronic) 0724-8741 (Linking) SP - 1859-69 ST - Validating new tuberculosis computational models with public whole cell screening aerobic activity datasets T2 - Pharm Res TI - Validating new tuberculosis computational models with public whole cell screening aerobic activity datasets UR - http://www.springerlink.com/content/58228876406x7556/ VL - 28 ID - 2619 ER - TY - JOUR AB - This paper deals with the problem of optimal control for the transmission dynamics of tuberculosis (TB). A TB model that considers the existence of a new class (mainly in the African context) is considered: the lost to follow up individuals. Based on the model formulated and studied in the work of Plaire Tchinda Mouofo, (2009), the TB control is formulated and solved as an optimal control theory problem using the Pontryagin's maximum principle (Pontryagin et al., 1992). This control strategy indicates how the control of the lost to follow up class can considerably influence the basic reproduction ratio so as to reduce the number of lost to follow up. Numerical results show the performance of the optimization strategy. AD - Laboratory of Applied Mathematics, University of Yaounde 1, Yaounde, Cameroon. yemvudu@yahoo.fr AN - 22007263 AU - Emvudu, Y. AU - Demasse, R. AU - Djeudeu, D. DO - 10.1155/2011/398476 [doi] DP - Nlm ET - 10/19 KW - Africa Algorithms Communicable Disease Control Follow-Up Studies Humans Lost to Follow-Up Models, Statistical Models, Theoretical Population Dynamics Poverty Public Health Tuberculosis/ therapy/ transmission World Health LA - eng N1 - Emvudu, Yves Demasse, Ramses Djeudeu, Dany United States Computational and mathematical methods in medicine Comput Math Methods Med. 2011;2011:398476. Epub 2011 Oct 11. PY - 2011 RN - fulltext fulltext_1208 SN - 1748-6718 (Electronic) 1748-670X (Linking) SP - 398476 ST - Optimal control of the lost to follow up in a tuberculosis model T2 - Comput Math Methods Med TI - Optimal control of the lost to follow up in a tuberculosis model UR - http://downloads.hindawi.com/journals/cmmm/2011/398476.pdf VL - 2011 ID - 2620 ER - TY - JOUR AB - Multiple immune factors control host responses to Mycobacterium tuberculosis infection, including the formation of granulomas, which are aggregates of immune cells whose function may reflect success or failure of the host to contain infection. One such factor is TNF-alpha. TNF-alpha has been experimentally characterized to have the following activities in M. tuberculosis infection: macrophage activation, apoptosis, and chemokine and cytokine production. Availability of TNF-alpha within a granuloma has been proposed to play a critical role in immunity to M. tuberculosis. However, in vivo measurement of a TNF-alpha concentration gradient and activities within a granuloma are not experimentally feasible. Further, processes that control TNF-alpha concentration and activities in a granuloma remain unknown. We developed a multiscale computational model that includes molecular, cellular, and tissue scale events that occur during granuloma formation and maintenance in lung. We use our model to identify processes that regulate TNF-alpha concentration and cellular behaviors and thus influence the outcome of infection within a granuloma. Our model predicts that TNF-alphaR1 internalization kinetics play a critical role in infection control within a granuloma, controlling whether there is clearance of bacteria, excessive inflammation, containment of bacteria within a stable granuloma, or uncontrolled growth of bacteria. Our results suggest that there is an interplay between TNF-alpha and bacterial levels in a granuloma that is controlled by the combined effects of both molecular and cellular scale processes. Finally, our model elucidates processes involved in immunity to M. tuberculosis that may be new targets for therapy. AD - Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109, USA. AN - 21321109 AU - Fallahi-Sichani, M. AU - El-Kebir, M. AU - Marino, S. AU - Kirschner, D. E. AU - Linderman, J. J. DA - Mar 15 DO - jimmunol.1003299 [pii] 10.4049/jimmunol.1003299 [doi] DP - Nlm ET - 02/16 KW - Computational Biology/ methods Granuloma/ immunology/microbiology/pathology Humans Inflammation Mediators/chemistry/metabolism/physiology Ligands Models, Immunological Molecular Dynamics Simulation Mycobacterium tuberculosis/ growth & development/ immunology/pathogenicity Predictive Value of Tests Receptors, Tumor Necrosis Factor, Type I/chemistry/metabolism/ physiology Signal Transduction/immunology Tuberculosis, Pulmonary/ immunology/microbiology/pathology Tumor Necrosis Factor-alpha/chemistry/metabolism/physiology LA - eng N1 - Fallahi-Sichani, Mohammad El-Kebir, Mohammed Marino, Simeone Kirschner, Denise E Linderman, Jennifer J N01 AI50018/AI/NIAID NIH HHS/United States R33 HL092844-01/HL/NHLBI NIH HHS/United States R33 HL092844-03/HL/NHLBI NIH HHS/United States R33 HL092853-01/HL/NHLBI NIH HHS/United States R33HL092844/HL/NHLBI NIH HHS/United States R33HL092853/HL/NHLBI NIH HHS/United States Research Support, N.I.H., Extramural United States Journal of immunology (Baltimore, Md. : 1950) Nihms291818 J Immunol. 2011 Mar 15;186(6):3472-83. Epub 2011 Feb 14. PY - 2011 RN - fulltext fulltext_1208 SN - 1550-6606 (Electronic) 0022-1767 (Linking) SP - 3472-83 ST - Multiscale computational modeling reveals a critical role for TNF-alpha receptor 1 dynamics in tuberculosis granuloma formation T2 - J Immunol TI - Multiscale computational modeling reveals a critical role for TNF-alpha receptor 1 dynamics in tuberculosis granuloma formation UR - http://www.jimmunol.org/content/186/6/3472.full.pdf VL - 186 ID - 2622 ER - TY - JOUR AB - To establish itself within the host system, Mycobacterium tuberculosis (Mtb) has formulated various means of attacking the host system. One such crucial strategy is the exploitation of the iron resources of the host system. Obtaining and maintaining the required concentration of iron becomes a matter of contest between the host and the pathogen, both trying to achieve this through complex molecular networks. The extent of complexity makes it important to obtain a systems perspective of the interplay between the host and the pathogen with respect to iron homeostasis. We have reconstructed a systems model comprising 92 components and 85 protein-protein or protein-metabolite interactions, which have been captured as a set of 194 rules. Apart from the interactions, these rules also account for protein synthesis and decay, RBC circulation and bacterial production and death rates. We have used a rule-based modelling approach, Kappa, to simulate the system separately under infection and non-infection conditions. Various perturbations including knock-outs and dual perturbation were also carried out to monitor the behavioral change of important proteins and metabolites. From this, key components as well as the required controlling factors in the model that are critical for maintaining iron homeostasis were identified. The model is able to re-establish the importance of iron-dependent regulator (ideR) in Mtb and transferrin (Tf) in the host. Perturbations, where iron storage is increased, appear to enhance nutritional immunity and the analysis indicates how they can be harmful for the host. Instead, decreasing the rate of iron uptake by Tf may prove to be helpful. Simulation and perturbation studies help in identifying Tf as a possible drug target. Regulating the mycobactin (myB) concentration was also identified as a possible strategy to control bacterial growth. The simulations thus provide significant insight into iron homeostasis and also for identifying possible drug targets for tuberculosis. AD - Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India. AN - 21833436 AU - Ghosh, S. AU - Prasad, K. V. AU - Vishveshwara, S. AU - Chandra, N. DA - Oct DO - 10.1039/c1mb05093a [doi] DP - Nlm ET - 08/13 KW - Homeostasis Iron/ metabolism Models, Biological Mycobacterium tuberculosis/ metabolism LA - eng N1 - Ghosh, Soma Prasad, K V S Vishveshwara, Saraswathi Chandra, Nagasuma Research Support, Non-U.S. Gov't England Molecular bioSystems Mol Biosyst. 2011 Oct;7(10):2750-68. Epub 2011 Aug 11. PY - 2011 RN - fulltext fulltext_1208 SN - 1742-2051 (Electronic) 1742-2051 (Linking) SP - 2750-68 ST - Rule-based modelling of iron homeostasis in tuberculosis T2 - Mol Biosyst TI - Rule-based modelling of iron homeostasis in tuberculosis UR - http://pubs.rsc.org/en/Content/ArticleLanding/2011/MB/c1mb05093a VL - 7 ID - 2623 ER - TY - JOUR AB - OBJECTIVES: To measure the economic costs and benefits of scaling up tuberculosis (TB) control under the Revised National Tuberculosis Control Programme (RNTCP) in India. DESIGN: Modelling based on country-level programme and epidemiological data from 1997 to 2006. RESULTS: The scale-up of TB control in India has resulted in a total health benefit of 29.2 million disability-adjusted life years (DALYs), including 1.3 million deaths averted. In 2006, the burden of TB measured in terms of DALYs lost would have been 1.8 times higher in the absence of the programme. The total gain in economic well-being from TB control is estimated at US$88.1 billion over the 1997-2006 10-year period. Total public expenditure on TB control over this period amounted to US$768 million, with the RNTCP accounting for US$299 million and other health sector costs accounting for US$469 million. The cost of TB control averaged just US$26 per DALY gained over 1997-2006 and generated a return of US$115 per dollar spent. CONCLUSIONS: The scale-up of TB control has been a very cost-effective strategy for improving the health status of India's population, while the return on investment has been exceptional from a societal perspective. AD - World Health Organization, New Delhi, India. goodchildm@hotmail.com AN - 21333103 AU - Goodchild, M. AU - Sahu, S. AU - Wares, F. AU - Dewan, P. AU - Shukla, R. S. AU - Chauhan, L. S. AU - Floyd, K. DA - Mar DP - Nlm ET - 02/22 KW - Cost-Benefit Analysis Directly Observed Therapy/economics Humans India Models, Economic National Health Programs/ economics Quality-Adjusted Life Years Tuberculosis/economics/ prevention & control LA - eng N1 - Goodchild, M Sahu, S Wares, F Dewan, P Shukla, R S Chauhan, L S Floyd, K Research Support, Non-U.S. Gov't France The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease Int J Tuberc Lung Dis. 2011 Mar;15(3):358-62. PY - 2011 RN - fulltext fulltext_1208 SN - 1815-7920 (Electronic) 1027-3719 (Linking) SP - 358-62 ST - A cost-benefit analysis of scaling up tuberculosis control in India T2 - Int J Tuberc Lung Dis TI - A cost-benefit analysis of scaling up tuberculosis control in India VL - 15 ID - 2624 ER - TY - JOUR AB - There is a critical need for improved and shorter tuberculosis (TB) treatment. Current in vitro models of TB, while valuable, are poor predictors of the antibacterial effect of drugs in vivo. Mathematical models may be useful to overcome the limitations of traditional approaches in TB research. The objective of this study was to set up a prototype mathematical model of TB treatment by rifampin, based on pharmacokinetic, pharmacodynamic and disease submodels. The full mathematical model can simulate the time-course of tuberculous disease from the first day of infection to the last day of therapy. Therapeutic simulations were performed with the full model to study the antibacterial effect of various dosage regimens of rifampin in lungs. The model reproduced some qualitative and quantitative properties of the bactericidal activity of rifampin observed in clinical data. The kill curves simulated with the model showed a typical biphasic decline in the number of extracellular bacteria consistent with observations in TB patients. Simulations performed with more simple pharmacokinetic/pharmacodynamic models indicated a possible role of a protected intracellular bacterial compartment in such a biphasic decline. This modeling effort strongly suggests that current dosage regimens of RIF may be further optimized. In addition, it suggests a new hypothesis for bacterial persistence during TB treatment. AD - Hospices Civils de Lyon, Groupement Hospitalier de Geriatrie, Service Pharmaceutique-ADCAPT, Francheville, France. sylvain.goutelle@chu-lyon.fr AN - 21605569 AU - Goutelle, S. AU - Bourguignon, L. AU - Jelliffe, R. W. AU - Conte, J. E., Jr. AU - Maire, P. DA - Aug 7 DO - S0022-5193(11)00255-4 [pii] 10.1016/j.jtbi.2011.05.013 [doi] DP - Nlm ET - 05/25 KW - Animals Antitubercular Agents/pharmacokinetics/pharmacology/ therapeutic use Mice Models, Theoretical Rifampin/pharmacokinetics/pharmacology/ therapeutic use Tuberculosis, Pulmonary/ drug therapy LA - eng N1 - Goutelle, Sylvain Bourguignon, Laurent Jelliffe, Roger W Conte, John E Jr Maire, Pascal England Journal of theoretical biology J Theor Biol. 2011 Aug 7;282(1):80-92. Epub 2011 May 18. PY - 2011 RN - fulltext fulltext_1208 SN - 1095-8541 (Electronic) 0022-5193 (Linking) SP - 80-92 ST - Mathematical modeling of pulmonary tuberculosis therapy: Insights from a prototype model with rifampin T2 - J Theor Biol TI - Mathematical modeling of pulmonary tuberculosis therapy: Insights from a prototype model with rifampin UR - http://ac.els-cdn.com/S0022519311002554/1-s2.0-S0022519311002554-main.pdf?_tid=876b5e7118fa0e117600e5bd358ef74d&acdnat=1345012412_e092be0a51c53045ce45abc61fdba41c VL - 282 ID - 2625 ER - TY - JOUR AB - Mathematical analysis is carried out for a tuberculosis (TB) model incorporating both latent and clinical stages, immigration and treatment. With immigration into the latent classes, we show that the model always has a unique endemic equilibrium and it is globally asymptotically stable. The global stability of the endemic equilibrium is proved using a global Lyapunov function. AU - Guo, h. AU - Li, M. Y. IS - 1 PY - 2011 SP - 1-18 ST - GLOBAL STABILITY OF THE ENDEMIC EQUILIBRIUM OF A TUBERCULOSIS MODEL WITH IMMIGRATION AND TREATMENT T2 - Canadian Applied Mathematics Quarterly TI - GLOBAL STABILITY OF THE ENDEMIC EQUILIBRIUM OF A TUBERCULOSIS MODEL WITH IMMIGRATION AND TREATMENT UR - http://www.math.ualberta.ca/ami/CAMQ/pdf_files/vol_19/19_1/19_1a.pdf VL - 19 ID - 4938 ER - TY - JOUR AB - Spread of tuberculosis (TB) due to the immigration from some developing countries with high TB incidence to developed countries poses an increasing challenge in the global TB control. Here a simple compartmental TB model with constant immigration, early and late latency is developed in order to investigate the impact of new immigrants with latent TB on the overall TB incidence, and to compare the difference contributed by different proportions of latently-infected new immigrants with high or low risk to develop active TB shortly after arrival. The global dynamics of the system is completely classified, numerical simulations are carried out for different scenarios, and potential applications to public health policy are discussed. AD - Centre for Disease Modeling, Department of Mathematics and Statistics, York University, 4700 Keele Street Toronto, ON, M3J 1P3, Canada. hguo@mathstat.yorku.ca AN - 21675805 AU - Guo, H. AU - Wu, J. DA - Jul DO - 10.3934/mbe.2011.8.695 DP - NLM ET - 2011/06/17 IS - 3 J2 - Mathematical biosciences and engineering : MBE KW - Canada/epidemiology Computer Simulation Disease Outbreaks/*statistics & numerical data Emigration and Immigration/*statistics & numerical data Humans Incidence *Models, Statistical Time Factors Tuberculosis/*epidemiology LA - eng N1 - 1551-0018 Guo, Hongbin Wu, Jianhong Journal Article Research Support, Non-U.S. Gov't United States Math Biosci Eng. 2011 Jul;8(3):695-709. doi: 10.3934/mbe.2011.8.695. PY - 2011 SN - 1547-1063 SP - 695-709 ST - Persistent high incidence of tuberculosis among immigrants in a low-incidence country: impact of immigrants with early or late latency T2 - Math Biosci Eng TI - Persistent high incidence of tuberculosis among immigrants in a low-incidence country: impact of immigrants with early or late latency VL - 8 ID - 2851 ER - TY - JOUR AB - Evidence of preferential mixing through selected social routes has been suggested for the transmission of tuberculosis (TB) infection in low burden settings. A realistic modelization of these contact routes is needed to appropriately assess the impact of individually targeted control strategies, such as contact network investigation of index cases and treatment of latent TB infection (LTBI). We propose an age-structured, socio-demographic individual based model (IBM) with a realistic, time-evolving structure of preferential contacts in a population. In particular, transmission within households, schools and workplaces, together with a component of casual, distance-dependent contacts are considered. We also compared the model against two other formulations having no social structure of contacts (homogeneous mixing transmission): a baseline deterministic model without age structure and an age-structured IBM. The socio-demographic IBM better fitted recent longitudinal data on TB epidemiology in Arkansas, USA, which serves as an example of a low burden setting. Inclusion of age structure in the model proved fundamental to capturing actual proportions of reactivated TB cases (as opposed to recently transmitted) as well as profiling age-group specific incidence. The socio-demographic structure additionally provides a prediction of TB transmission rates (the rate of infection in household contacts and the rate of secondary cases in household and workplace contacts). These results suggest that the socio-demographic IBM is an optimal choice for evaluating current control strategies, including contact network investigation of index cases, and the simulation of alternative scenarios, particularly for TB eradication targets. AD - Fondazione Bruno Kessler, Trento, Italy. guzzetta@fbk.eu AN - 21906603 AU - Guzzetta, G. AU - Ajelli, M. AU - Yang, Z. AU - Merler, S. AU - Furlanello, C. AU - Kirschner, D. DA - Nov 21 DO - S0022-5193(11)00435-8 [pii] 10.1016/j.jtbi.2011.08.032 [doi] DP - Nlm ET - 09/13 KW - Adolescent Adult Age Distribution Age Factors Aged Arkansas/epidemiology Child Child, Preschool Contact Tracing Endemic Diseases Epidemiologic Methods Humans Infant Infant, Newborn Interpersonal Relations Latent Tuberculosis/epidemiology Middle Aged Models, Biological Tuberculosis/epidemiology/prevention & control/ transmission Young Adult LA - eng N1 - Guzzetta, Giorgio Ajelli, Marco Yang, Zhenhua Merler, Stefano Furlanello, Cesare Kirschner, Denise R01 EB012579-04A1/EB/NIBIB NIH HHS/United States R01 HL106804-01/HL/NHLBI NIH HHS/United States R01-EB-012579-04/EB/NIBIB NIH HHS/United States R01-HL-106804-01/HL/NHLBI NIH HHS/United States R33 HL092853-01/HL/NHLBI NIH HHS/United States R33HL092853-01/HL/NHLBI NIH HHS/United States Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't England Journal of theoretical biology Nihms327860 J Theor Biol. 2011 Nov 21;289:197-205. Epub 2011 Sep 3. PY - 2011 RN - fulltext fulltext_1208 SN - 1095-8541 (Electronic) 0022-5193 (Linking) SP - 197-205 ST - Modeling socio-demography to capture tuberculosis transmission dynamics in a low burden setting T2 - J Theor Biol TI - Modeling socio-demography to capture tuberculosis transmission dynamics in a low burden setting UR - http://ac.els-cdn.com/S0022519311004358/1-s2.0-S0022519311004358-main.pdf?_tid=51cf6280baf7343d83850525bdaed5d3&acdnat=1345012454_66e6a3a6ba3270670d4232cc72803123 VL - 289 ID - 2626 ER - TY - JOUR AB - Tuberculosis (TB) is a growing problem worldwide, with an estimated third of the world's population currently infected. Of particular concern is the growing trend of dual epidemics of HIV and TB, with the associated multidrug-resistant TB (MDR-TB). Developed countries which had previously removed TB transmission from communities are being re-infected with the MDR-TB strains. In the USA, Centers for Disease Control & Prevention (2009) estimate that treatment of a single case of MDR-TB costs approximately USD$250,000, with a similar cost expected in Australia. TB is a complicated disease with different rates of progression to, and different aspects of, the clinically active disease. Approximately 5-10% of those infected with TB develop 'fast' TB, and are expected to progress to clinically active TB within 2 years [Porco et al. 2001]. The remainder have 'slow' TB, and remain latently infected, with 5-10% progressing to clinically active TB in 20 years [Blower et al. 1995]. Those with clinically active TB are further divided into extra-pulmonary (non-infectious) and pulmonary (able to infect others). Note those in the 'pulmonary' category may also have extra-pulmonary TB, but the reverse is not true. The control of TB spread is of paramount importance. The main intervention strategy adopted by the World Health Organisation (WHO) Stop TB program is the 'Directly Observed Treatment Short course' (DOTS) [World Health Organisation 2010]. Not all detection occurs under this program, but a significant amount of the treatment does, particularly for high burden countries. Therefore when considering interventions, we concentrate on the DOTS program, and do not consider other interventions here. We develop a population level model for TB transmission, with a focus on incorporating the WHO's DOTS (Directly Observed Treatment Short-course) intervention program. The population is divided into 6 compartments, with 4 describing different stages of the disease (susceptible, latently infected, extrapulmonary, and pulmonary), and 2 for the DOTS intervention program (detection and treatment). This work has applications worldwide, but here we focus on the Torres Strait region where there is a high proportion of multidrug-resistant TB (MDR-TB). In particular, estimates suggest Papua New Guinea (PNG) may have the highest proportion of MDR-TB in the world [Gilpin et al. 2008], and the Torres Strait Islands could potentially act as a gateway for MDR-TB into mainland Australia. A sensitivity analysis is important in terms of both data collection and refinement, and in the context of understanding and informing the control of TB. To perform the sensitivity analysis the model needs to be run many times with different parameter values. Latin hypercube sampling is used to efficiently cover the parameter space, in conjunction with partial rank correlation coefficient to determine which parameters most influence the disease dynamics. The results show the most important parameter for TB in Papua New Guinea (PNG) is the rate of progression from latent to clinically active TB. Therefore, data refinement should concentrate on determining this rate as accurately as possible. The most important intervention parameter is the detection rate for the DOTS intervention program. This suggests an increase in DOTS coverage by even a small margin will result in a significant decrease in the incidence and prevalence of TB in PNG and other high burden countries. AD - Australian Natl Univ, Natl Ctr Epidemiol & Populat Hlth, Canberra, ACT 0200, Australia AN - WOS:000314989300125 AU - Hickson, R. I. AU - Mercer, G. N. AU - Lokuge, M. KW - tuberculosis infectious disease control intervention dots sensitivity analysis transmission dynamics cost-effectiveness western province drug-resistance hiv strategies uncertainty countries papua tb LA - English N1 - Bdu79 Times Cited:2 Cited References Count:23 PY - 2011 SP - 926-932 ST - Sensitivity analysis of a model for tuberculosis T2 - 19th International Congress on Modelling and Simulation (Modsim2011) TI - Sensitivity analysis of a model for tuberculosis UR - ://WOS:000314989300125 ID - 4875 ER - TY - JOUR AB - Tuberculosis (TB) is a global emergency. The World Health Organization reports about 9.2 million new infections each year, with an average of 1.7 million people killed by the disease. The causative agent is Mycobacterium tuberculosis (Mtb), whose main target are the macrophages, important immune system cells. Macrophages and T cell populations are the main responsible for fighting the pathogen. A better understanding of the interaction between Mtb, macrophages and T cells will contribute to the design of strategies to control TB. The purpose of this study is to evaluate the impact of the response of T cells and macrophages in the control of Mtb. To this end, we propose a system of ordinary differential equations to model the interaction among non-infected macrophages, infected macrophages, T cells and Mtb bacilli. Model analysis reveals the existence of two equilibrium states, infection-free equilibrium and the endemically infected equilibrium which can represent a state of latent or active infection, depending on the amount of bacteria. AD - Departamento de Matematicas y Estadistica, Universidad de Narino, Pasto, Clle 18 - Cra 50, Colombia. edbargun@udenar.edu.co AN - 21936595 AU - Ibarguen-Mondragon, E. AU - Esteva, L. AU - Chavez-Galan, L. DA - Oct 01 DO - 10.3934/mbe.2011.8.973 IS - 4 KW - Basic Reproduction Number Computer Simulation Humans Immunity, Cellular/immunology Macrophages/*immunology/microbiology *Models, Immunological Mycobacterium tuberculosis/*immunology T-Lymphocytes/*immunology/microbiology Tuberculosis/*immunology/microbiology/prevention & control N1 - Ibarguen-Mondragon, Eduardo Esteva, Lourdes Chavez-Galan, Leslie eng Research Support, Non-U.S. Gov't 2011/09/23 06:00 Math Biosci Eng. 2011 Oct 1;8(4):973-86. doi: 10.3934/mbe.2011.8.973. PY - 2011 SN - 1551-0018 (Electronic) 1547-1063 (Linking) SP - 973-86 ST - A mathematical model for cellular immunology of tuberculosis T2 - Math Biosci Eng TI - A mathematical model for cellular immunology of tuberculosis UR - https://www.ncbi.nlm.nih.gov/pubmed/21936595 VL - 8 ID - 2235 ER - TY - JOUR AB - For pathogens that must be treated with combinations of antibiotics and acquire resistance through genetic mutation, knowledge of the order in which drug-resistance mutations occur may be important for determining treatment policies. Diagnostic specimens collected from patients are often available; this makes it possible to determine the presence of individual drug resistance-conferring mutations and combinations of these mutations. In most cases, these specimens are only available from a patient at a single point in time; it is very rare to have access to multiple specimens from a single patient collected over time as resistance accumulates to multiple drugs. Statistical methods that use branching trees have been successfully applied to such cross-sectional data to make inference on the ordering of events that occurred prior to sampling. Here, we propose a Bayesian approach to fitting branching tree models that has several advantages, including the ability to accommodate prior information regarding measurement error or cross resistance and the natural way it permits the characterization of uncertainty. Our methods are applied to a data set for drug-resistant TB in Peru; the goal of the analysis was to determine the order with which patients develop resistance to the drugs commonly used for treating TB in this setting. AD - Harvard School of Public Health, 655 Huntington Avenue, Boston, MA 02115, USA. aizu@hsph.harvard.edu AN - 21717491 AU - Izu, A. AU - Cohen, T. AU - Mitnick, C. AU - Murray, M. AU - De Gruttola, V. DA - Sep 30 DO - 10.1002/sim.4287 [doi] 10.1002/sim.4287. Epub 2011 Jun 30. DP - Nlm ET - 07/01 KW - Anti-Bacterial Agents/ pharmacology Bayes Theorem Computer Simulation Drug Resistance, Multiple, Bacterial Humans Models, Genetic Models, Statistical Mutation Mycobacterium tuberculosis/drug effects/ genetics Tuberculosis/drug therapy/ microbiology L1 - internal-pdf://0048581990/Izu-2011-Bayesian methods for fitting mixture.pdf LA - eng PY - 2011 RN - fulltext fulltext_1208 SN - 1097-0258 (Electronic) 0277-6715 (Linking) SP - 2708-20 ST - Bayesian methods for fitting mixture models that characterize branching tree processes: An application to development of resistant TB strains T2 - Stat Med TI - Bayesian methods for fitting mixture models that characterize branching tree processes: An application to development of resistant TB strains UR - http://onlinelibrary.wiley.com.ez.lshtm.ac.uk/store/10.1002/sim.4287/asset/sim4287.pdf?v=1&t=h5w1m62j&s=09334abd6f823c09c5f187f158f8e5341cba1933 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3219798/pdf/nihms321244.pdf VL - 30 ID - 2627 ER - TY - JOUR AB - Children with tuberculosis present with high rates of disseminated disease and tuberculous (TB) meningitis due to poor cell-mediated immunity. Recommended isoniazid doses vary from 5 mg/kg/day to 15 mg/kg/day. Antimicrobial pharmacokinetic/pharmacodynamic studies have demonstrated that the ratio of the 0- to 24-h area under the concentration-time curve (AUC(0-24)) to the MIC best explains isoniazid microbial kill. The AUC(0-24)/MIC ratio associated with 80% of maximal kill (80% effective concentration [EC(80)]), considered the optimal effect, is 287.2. Given the pharmacokinetics of isoniazid encountered in children 10 years old or younger, with infants as a special group, and given the differences in penetration of isoniazid into phagocytic cells, epithelial lining fluid, and subarachnoid space during TB meningitis, we performed 10,000 patient Monte Carlo simulations to determine how well isoniazid doses of between 2.5 and 40 mg/kg/day would achieve or exceed the EC(80). None of the doses examined achieved the EC(80) in >/=90% of children. Doses of 5 mg/kg were universally inferior; doses of 10 to 15 mg/kg/day were adequate only under the very limited circumstances of children who were slow acetylators and had disease limited to pneumonia. Each of the three disease syndromes, acetylation phenotype, and being an infant required different doses to achieve adequate AUC(0-24)/MIC exposures in an acceptable proportion of children. We conclude that current recommended doses for children are likely suboptimal and that isoniazid doses in children are best individualized based on disease process, age, and acetylation status. AD - Department of Paediatrics and Child Health, University of KwaZulu-Natal, Durban, South Africa. AN - 21098246 AU - Jeena, P. M. AU - Bishai, W. R. AU - Pasipanodya, J. G. AU - Gumbo, T. C2 - PMC3028779 DA - Feb DO - 10.1128/aac.00763-10 DP - NLM ET - 2010/11/26 IS - 2 J2 - Antimicrobial agents and chemotherapy KW - Animals Antitubercular Agents/*administration & dosage/pharmacokinetics/pharmacology Area Under Curve Cerebrospinal Fluid/metabolism Child Child, Preschool *Computer Simulation Dose-Response Relationship, Drug Humans Immunity, Cellular Infant Isoniazid/*administration & dosage/pharmacokinetics/pharmacology Mice Microbial Sensitivity Tests Models, Biological *Monte Carlo Method Mycobacterium tuberculosis/*drug effects Phagocytes/metabolism Treatment Outcome Tuberculosis/*drug therapy/microbiology Tuberculosis, Meningeal/drug therapy/microbiology LA - eng N1 - 1098-6596 Jeena, Prakash M Bishai, William R Pasipanodya, Jotam G Gumbo, Tawanda Howard Hughes Medical Institute/United States Journal Article Research Support, Non-U.S. Gov't United States Antimicrob Agents Chemother. 2011 Feb;55(2):539-45. doi: 10.1128/AAC.00763-10. Epub 2010 Nov 22. PY - 2011 SN - 0066-4804 SP - 539-45 ST - In silico children and the glass mouse model: clinical trial simulations to identify and individualize optimal isoniazid doses in children with tuberculosis T2 - Antimicrob Agents Chemother TI - In silico children and the glass mouse model: clinical trial simulations to identify and individualize optimal isoniazid doses in children with tuberculosis VL - 55 ID - 2134 ER - TY - JOUR AB - In order to better predict epidemic of tuberculosis (TB) and evaluate the effect of TB control strategies, we added the effect of transmission from permanent residents to migrants to our previous TB model. We simulated the behavior of TB transmission by the extended model. The numerical simulation indicated that the basic reproductive numbers must be less than one in both permanent residents and migrants in order to eliminate the disease from total population. We also evaluated the Canada's TB screening strategy and observe that TB is sensitive to the strategy. Our study suggests that immigrants have a considerable influence on the overall transmission dynamics behavior of tuberculosis. The effective TB control measures should incorporate migrant as well the permanent residents. AD - National Institute on Drug Dependence, Peking University, Beijing, China National Center for Tuberculosis Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China National Institute of Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing, China. AN - 21342483 AU - Jia, Z. AU - Cheng, S. AU - Jia, X. DA - Feb 5 DO - 10.1111/j.1756-5391.2011.01116.x [doi] 10.1111/j.1756-5391.2011.01116.x. DP - Nlm ET - 02/24 LA - Eng PY - 2011 RN - fulltext fulltext_1208 SN - 1756-5391 (Electronic) 1756-5391 (Linking) ST - A Mathematical model for evaluating tuberculosis screening strategies T2 - J Evid Based Med TI - A Mathematical model for evaluating tuberculosis screening strategies UR - http://onlinelibrary.wiley.com/doi/10.1111/j.1756-5391.2011.01116.x/abstract ID - 2628 ER - TY - JOUR AB - BACKGROUND: Currently, an annual chest X-ray examination (CXR) for detection of active tuberculosis (TB) in employees aged >/=40 years is recommended in the guidelines of the Japan Industrial Safety and Health Law. Interferon-gamma release assays are new alternatives to the tuberculin skin test for detecting Mycobacterium tuberculosis infection, with higher specificity than the tuberculin skin test and without cross-reactivity with the Bacille Calmette-Guerin vaccine. This study aimed to assess the cost-effectiveness of employee TB screening using QuantiFERON-TB Gold In-Tube (QFT) versus CXR. METHODS: Markov models were constructed. The target population was a hypothetical cohort of immunocompetent 40-year-old individuals, using a societal perspective and a lifetime horizon. All costs and clinical benefits were discounted at a fixed annual rate of 3%. RESULTS: In a base-case analysis, the QFT strategy was the most cost-effective ($US 262.84; 22.87049 quality-adjusted life-years [QALYs]) compared with no screening ($448.38; 22.85452 QALYs) and CXR ($543.50; 22.85453 QALYs) [year 2009 values]. CONCLUSION: The QFT strategy is currently robust for screening Bacille Calmette-Guerin- vaccinated employees in Japan. There appears to be little role for CXR. These findings may be applicable to other countries in terms of choosing optimal TB screening for employees. AD - Public Health Promotion Division, Tamagawa District Administration Office, City of Setagaya, Tokyo, Japan. Kowada101@mb.city.setagaya.tokyo.jp AN - 21839543 AU - Kowada, A. DA - Dec DO - 10.1016/j.ajic.2011.04.329 DP - Nlm ET - 08/16 J2 - American journal of infection control KW - Adult Cost-Benefit Analysis Female Health Personnel Humans Interferon-gamma Release Tests/ economics/methods Japan Male Occupational Health Radiography, Thoracic/ economics/methods Tuberculosis/ diagnosis X-Rays LA - eng N1 - Kowada, Akiko United States Am J Infect Control. 2011 Dec;39(10):e67-72. Epub 2011 Aug 12. PY - 2011 RN - fulltext fulltext_1208 SN - 1527-3296 (Electronic) 0196-6553 (Linking) SP - e67-72 ST - Cost-effectiveness of interferon-gamma release assay versus chest X-ray for tuberculosis screening of employees T2 - Am J Infect Control TI - Cost-effectiveness of interferon-gamma release assay versus chest X-ray for tuberculosis screening of employees UR - http://ac.els-cdn.com/S0196655311007255/1-s2.0-S0196655311007255-main.pdf?_tid=991548c8-f1d4-11e1-902d-00000aab0f01&acdnat=1346243300_adc9202a2f12935cc68bcb3623f56bdd VL - 39 ID - 2630 ER - TY - JOUR AN - 21440954 AU - Kowada, A. AU - Deshpande, G. A. AU - Takahashi, O. AU - Shimbo, T. AU - Fukui, T. DA - Jun DO - 10.1016/j.jhin.2011.01.026 DP - Nlm ET - 03/29 J2 - The Journal of hospital infection KW - Adult Cost-Benefit Analysis Health Personnel Humans Immunologic Tests/ economics Incidence Interferon-gamma/ biosynthesis Latent Tuberculosis/diagnosis/epidemiology/immunology/radiography Markov Chains Mass Chest X-Ray/ economics Mass Screening/ economics Middle Aged Mycobacterium tuberculosis/immunology Tuberculosis, Pulmonary/ diagnosis/epidemiology/immunology/radiography LA - eng N1 - Kowada, A Deshpande, G A Takahashi, O Shimbo, T Fukui, T Letter England J Hosp Infect. 2011 Jun;78(2):152-4. Epub 2011 Mar 26. PY - 2011 RN - fulltext fulltext_1208 SN - 1532-2939 (Electronic) 0195-6701 (Linking) SP - 152-4 ST - Cost-effectiveness analysis of interferon-gamma release assays versus chest X-ray for annual tuberculosis screening of healthcare workers T2 - J Hosp Infect TI - Cost-effectiveness analysis of interferon-gamma release assays versus chest X-ray for annual tuberculosis screening of healthcare workers UR - http://ac.els-cdn.com/S0195670111000909/1-s2.0-S0195670111000909-main.pdf?_tid=9495ff54-f1d4-11e1-bda6-00000aab0f01&acdnat=1346243292_bc75a6a0ca9018638c484814e10f3c09 VL - 78 ID - 2631 ER - TY - JOUR AU - Li, Xue-Zhi AU - Bhattacharya, Souvik AU - Yang, Jun-Yuan AU - Martcheva, Maia DO - doi:10.1142/S0218339011003889 PY - 2011 RN - fulltext fulltext_1208 SP - 205-236 ST - A TUBERCULOSIS (TB) MODEL WITH UNDETECTED COMPARTMENT: AN APPLICATION TO CHINA T2 - Journal of Biological Systems TI - A TUBERCULOSIS (TB) MODEL WITH UNDETECTED COMPARTMENT: AN APPLICATION TO CHINA UR - http://www.worldscientific.com/doi/abs/10.1142/S0218339011003889 VL - 19 ID - 2632 ER - TY - JOUR AB - Efforts to stimulate technological innovation in the diagnosis of tuberculosis (TB) have resulted in the recent introduction of several novel diagnostic tools. As these products come to market, policy makers must make difficult decisions about which of the available tools to implement. This choice should depend not only on the test characteristics (e.g., sensitivity and specificity) of the tools, but also on how they will be used within the existing health care infrastructure. Accordingly, policy makers choosing between diagnostic strategies must decide: 1) What is the best combination of tools to select? 2)Who should be tested with the new tools? and 3)Will these tools complement or replace existing diagnostics? The best choice of diagnostic strategy will likely vary between settings with different epidemiology (e.g., levels of TB incidence, human immunodeficiency virus co-infection and drug-resistant TB) and structural and resource constraints (e.g., existing diagnostic pathways, human resources and laboratory capacity). We propose a joint modelling framework that includes a tuberculosis (TB) transmission component (a dynamic epidemiological model) and a health system component (an operational systems model) to support diagnostic strategy decisions. This modelling approach captures the complex feedback loops in this system: new diagnostic strategies alter the demands on and performance of health systems that impact TB transmission dynamics which, in turn, result in further changes to demands on the health system. We demonstrate the use of a simplified model to support the rational choice of a diagnostic strategy based on health systems requirements, patient outcomes and population-level TB impact. AD - Institute of Epidemiology and Preventive Medicine, National Taiwan University, Taipei, Taiwan. AN - 21740663 AU - Lin, H. H. AU - Langley, I. AU - Mwenda, R. AU - Doulla, B. AU - Egwaga, S. AU - Millington, K. A. AU - Mann, G. H. AU - Murray, M. AU - Squire, S. B. AU - Cohen, T. DA - Aug DO - 10.5588/ijtld.11.0062 ET - 07/12 J2 - The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease KW - Antitubercular Agents/therapeutic use *Bacteriological Techniques/economics Computer Simulation *Decision Support Techniques Feedback Health Care Costs Health Policy Health Resources/economics/utilization Humans Policy Making Predictive Value of Tests Prognosis Sensitivity and Specificity Sputum/microbiology Time Factors Tuberculosis/*diagnosis/drug therapy/economics/epidemiology/transmission LA - eng M3 - Research Support, Non-U.S. Gov't N1 - Lin, H-H Langley, I Mwenda, R Doulla, B Egwaga, S Millington, K A Mann, G H Murray, M Squire, S B Cohen, T France Int J Tuberc Lung Dis. 2011 Aug;15(8):996-1004. PY - 2011 RN - hiv_tb_Sep2012 fulltext fulltext_1208 SN - 1815-7920 (Electronic) 1027-3719 (Linking) SP - 996-1004 ST - A modelling framework to support the selection and implementation of new tuberculosis diagnostic tools T2 - Int J Tuberc Lung Dis TI - A modelling framework to support the selection and implementation of new tuberculosis diagnostic tools UR - http://www.ncbi.nlm.nih.gov/pubmed/21740663 VL - 15 ID - 2634 ER - TY - JOUR AB - RATIONALE: To improve the effectiveness of tuberculosis (TB) control programs in the United States by identifying cost-effective priorities for screening for latent tuberculosis infection (LTBI). OBJECTIVES: To estimate the cost-effectiveness of LTBI screening using the tuberculin skin test (TST)and interferon-g release assays (IGRAs). METHODS: A Markov model of screening for LTBI with TST and IGRA in risk-groups considered in current LTBI screening guidelines. MEASUREMENTS AND MAIN RESULTS: In all risk-groups, TST and IGRA screening resulted in increased mean life expectancy, ranging from 0.03-0.24 life-months per person screened. IGRA screening resulted in greater life expectancy gains than TST. Screening always cost more than not screening, but IGRA was cost-saving compared with TST in some groups. Four patterns of cost-effectiveness emerged, related to four risk categories. (1) Individuals at highest risk of TB reactivation (close contacts and those infected with HIV): the incremental cost-effectiveness ratio (ICER) of IGRA compared with TST was less than $100,000 per quality-adjusted life year (QALY) gained. (2) The foreign-born: IGRA was cost-saving compared with TST and cost-effective compared with no screening (ICER ,$100,000 per QALY gained). (3) Vulnerable populations (e.g., homeless, drug user, or former prisoner): the ICER of TST screening was approximately $100,000-$150,000 per QALY gained, but IGRA was not cost-effective. (4) Medical comorbidities (e.g., diabetes): the ICER of screening with TST or IGRA was greater than $100,000 per QALY. CONCLUSIONS: LTBI screening guidelines could make progress toward TB elimination by prioritizing screening for close contacts, those infected with HIV, and the foreign-born regardless of time living in the United States. For these groups, IGRA screening was more cost-effective than TST screening. AD - HIV Epidemiology and Outcomes Research Unit, Boston Medical Center, Section of Infectious Disease, Evans Biomedical Research Center, 650 Albany St. Rm 647, Boston, MA 02118, USA. benjamin.linas@bmc.org AN - 21562129 AU - Linas, B. P. AU - Wong, A. Y. AU - Freedberg, K. A. AU - Horsburgh, C. R., Jr. DO - 201101-0181OC [pii] 10.1164/rccm.201101-0181OC KW - Adolescent Adult Aged Aged, 80 and over Child Contact Tracing/economics/methods Cost Savings Cost-Benefit Analysis Female Humans Incidence Interferon-gamma/secretion Latent Tuberculosis/diagnosis/*epidemiology/therapy Male *Mass Screening/economics/methods/standards Middle Aged *Models, Economic Morbidity/trends Practice Guidelines as Topic Prevalence Quality-Adjusted Life Years Retrospective Studies Tuberculin Test/*economics United States/epidemiology Young Adult LA - eng N1 - Linas, Benjamin P Wong, Angela Y Freedberg, Kenneth A Horsburgh, C Robert Jr K01AI073193/AI/NIAID NIH HHS/United States K24AI062476/AI/NIAID NIH HHS/United States R37AI42006/AI/NIAID NIH HHS/United States Comparative Study Research Support, N.I.H., Extramural United States American journal of respiratory and critical care medicine Am J Respir Crit Care Med. 2011 Sep 1;184(5):590-601. PY - 2011 RN - fulltext fulltext_1208 SN - 1535-4970 (Electronic) 1073-449X (Linking) SP - 590-601 ST - Priorities for screening and treatment of latent tuberculosis infection in the United States T2 - American journal of respiratory and critical care medicine TI - Priorities for screening and treatment of latent tuberculosis infection in the United States UR - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=21562129http://ajrccm.atsjournals.org/content/184/5/590.long VL - 184 ID - 2635 ER - TY - JOUR AB - A deterministic model is developed to describe the effects of vaccination and treatment on the spread of tuberculosis. It is shown that the basic reproduction number characterizes the disease transmission dynamics: if R 0 ≤ 1 , there exists only the disease-free equilibrium which is globally asymptotically stable, and if R 0 > 1 then there is a disease endemic equilibrium and the disease persists. Global stability of the endemic equilibrium is also discussed. Analysis of the dependence of R 0 on the vaccination rate, vaccine efficacy and treatment rate shows that the spread of tuberculosis can be controlled if the vaccine rate or the efficacy or the treatment rate reaches a certain threshold. AU - Liu, Junli AU - Zhang, Tailei DO - 10.1016/j.mcm.2011.03.033 KW - Tuberculosis Vaccination Treatment Lyapunov function Global stability PY - 2011 RN - fulltext fulltext_1208 SN - 0895-7177 SP - 836-845 ST - Global stability for a tuberculosis model T2 - Mathematical and Computer Modelling TI - Global stability for a tuberculosis model UR - http://www.sciencedirect.com/science/article/pii/S0895717711001932http://ac.els-cdn.com/S0895717711001932/1-s2.0-S0895717711001932-main.pdf?_tid=6e401a810ebafd6a2b564ba57d5e7e04&acdnat=1345012593_1c343b0c8216062a71c1fa8ef9a99469 VL - 54 ID - 2636 ER - TY - JOUR AB - This paper presents a novel mathematical model with multidrug-resistant (MDR) and undetected TB cases. The theoretical analysis indicates that the disease-free equilibrium is globally asymptotically stable if R(0) < 1; otherwise, the system may exist a locally asymptotically stable endemic equilibrium. The model is also used to simulate and predict TB epidemic in Guangdong. The results imply that our model is in agreement with actual data and the undetected rate plays vital role in the TB trend. Our model also implies that TB cannot be eradicated from population if it continues to implement current TB control strategies. AD - Jia, ZW Peking Univ, Natl Inst Drug Dependence, Beijing 100083, Peoples R China Peking Univ, Natl Inst Drug Dependence, Beijing 100083, Peoples R China Peking Univ, Natl Inst Drug Dependence, Beijing 100083, Peoples R China S China Univ Technol, Coll Automat Sci & Engn, Guangzhou 510640, Guangdong, Peoples R China N Univ China, Dept Math, Taiyuan 030051, Peoples R China AntiTB Res Inst Guangdong Prov, Guangzhou 510630, Guangdong, Peoples R China AN - WOS:000293568100001 AU - Liu, Y. Q. AU - Sun, Z. D. AU - Sun, G. Q. AU - Zhong, Q. AU - Jiang, L. AU - Zhou, L. AU - Qiao, Y. P. AU - Jia, Z. W. DO - Artn 296905 10.1155/2011/296905 J2 - Discrete Dyn Nat Soc L1 - internal-pdf://0733788662/Liu-2011-Modeling Transmission of Tuberculosis.pdf LA - English N1 - 803fv Times Cited:0 Cited References Count:10 PY - 2011 SN - 1026-0226 ST - Modeling Transmission of Tuberculosis with MDR and Undetected Cases T2 - Discrete Dynamics in Nature and Society TI - Modeling Transmission of Tuberculosis with MDR and Undetected Cases UR - ://WOS:000293568100001 http://downloads.hindawi.com/journals/ddns/2011/296905.pdf ID - 4876 ER - TY - JOUR AB - The majority of individuals infected with Mycobacterium tuberculosis (Mtb) bacilli develop latent infection. Mtb becomes dormant and phenotypically drug resistant when it encounters multiple stresses within the host, and expresses a set of genes, known as the dormancy regulon, in vivo. These genes are expressed in vitro in response to nitric oxide (NO), hypoxia (oxygen deprivation), and nutrient starvation. The occurrence and reactivation of latent tuberculosis (TB) is not clearly understood. The ability of the pathogen to enter and exit from different states is associated with its ability to cause persistent infection. During infection it is not known whether the organism is in a persistent slow replicating state or a dormant non-replicating state, with the latter ultimately causing a latent infection with the potential to reactivate to active disease. We collected gene expression data for Mtb bacilli under different stress conditions that simulate latency or dormancy. Time course experiments were selected and differentially expressed gene profiles were determined at each time point. A mathematical model was then developed to show the dynamics of Mtb latency based on the profile of differentially expressed genes. Analysis of the time course data show the dynamics of latency occurrence in vitro and the mathematical model reveals all possible scenarios of Mtb latency development with respect to the different conditions that may be produced by the immune response in vivo. The mathematical model provides a biological explanation of how Mtb latency occurs based on observed gene expression changes in in vitro latency models. AD - University of Cape Town, Institute of Infectious Disease and Molecular Medicine, Department of Clinical Laboratory Sciences, Cape Town, South Africa. gesham.magombedze@uct.ac.za