{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,8]],"date-time":"2026-04-08T22:25:27Z","timestamp":1775687127883,"version":"3.50.1"},"reference-count":30,"publisher":"Public Library of Science (PLoS)","issue":"11","license":[{"start":{"date-parts":[[2021,11,19]],"date-time":"2021-11-19T00:00:00Z","timestamp":1637280000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100007601","name":"Horizon 2020","doi-asserted-by":"publisher","award":["733174"],"award-info":[{"award-number":["733174"]}],"id":[{"id":"10.13039\/501100007601","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000865","name":"Bill and Melinda Gates Foundation","doi-asserted-by":"publisher","award":["OPP1184344"],"award-info":[{"award-number":["OPP1184344"]}],"id":[{"id":"10.13039\/100000865","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:sec id=\"sec001\">\n<jats:title>Background<\/jats:title>\n<jats:p>In the last decade, active case finding (ACF) strategies for tuberculosis (TB) have been implemented in many diverse settings, with some showing large increases in case detection and reporting at the sub-national level. There have also been several studies which seek to provide evidence for the benefits of ACF to individuals and communities in the broader context. However, there remains no quantification of the impact of ACF with regards to reducing the burden of transmission. We sought to address this knowledge gap and quantify the potential impact of active case finding on reducing transmission of TB at the national scale and further, to determine the intensification of intervention efforts required to bring the reproduction number (<jats:italic>R<\/jats:italic><jats:sub>0<\/jats:sub>) below 1 for TB.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec002\">\n<jats:title>Methods<\/jats:title>\n<jats:p>We adopt a dynamic transmission model that incorporates heterogeneity in risk to TB to assess the impact of an ACF programme (IMPACT TB) on reducing TB incidence in Vietnam and Nepal. We fit the models to country-level incidence data using a Bayesian Markov Chain Monte Carlo approach. We assess the impact of ACF using a parameter in our model, which we term the treatment success rate. Using programmatic data, we estimate how much this parameter has increased as a result of IMPACT TB in the implementation districts of Vietnam and Nepal and quantify additional efforts needed to eliminate transmission of TB in these countries by 2035.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec003\">\n<jats:title>Results<\/jats:title>\n<jats:p>Extending the IMPACT TB programme to national coverage would lead to moderate decreases in TB incidence and would not be enough to interrupt transmission by 2035. Decreasing transmission sufficiently to bring the reproduction number (R0) below 1, would require a further intensification of current efforts, even at the sub-national level.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec004\">\n<jats:title>Conclusions<\/jats:title>\n<jats:p>Active case finding programmes are effective in reducing TB in the short term. However, interruption of transmission in high-burden countries, like Vietnam and Nepal, will require comprehensive incremental efforts. Complementary measures to reduce progression from infection to disease, and reactivation of latent infection, are needed to meet the WHO End TB incidence targets.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pone.0257242","type":"journal-article","created":{"date-parts":[[2021,11,19]],"date-time":"2021-11-19T18:33:44Z","timestamp":1637346824000},"page":"e0257242","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":10,"title":["The impact of active case finding on transmission dynamics of tuberculosis: A modelling study"],"prefix":"10.1371","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7005-6734","authenticated-orcid":true,"given":"Diepreye Victoria","family":"Ayabina","sequence":"first","affiliation":[]},{"given":"M. Gabriela M.","family":"Gomes","sequence":"additional","affiliation":[]},{"given":"Nhung Viet","family":"Nguyen","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5937-6286","authenticated-orcid":true,"given":"Luan","family":"Vo","sequence":"additional","affiliation":[]},{"given":"Suvesh","family":"Shreshta","sequence":"additional","affiliation":[]},{"given":"Anil","family":"Thapa","sequence":"additional","affiliation":[]},{"given":"Andrew James","family":"Codlin","sequence":"additional","affiliation":[]},{"given":"Gokul","family":"Mishra","sequence":"additional","affiliation":[]},{"given":"Maxine","family":"Caws","sequence":"additional","affiliation":[]}],"member":"340","published-online":{"date-parts":[[2021,11,19]]},"reference":[{"key":"pone.0257242.ref001","unstructured":"WHO. Global Tuberculosis Report 2018."},{"key":"pone.0257242.ref002","first-page":"1799","article-title":"The WHO\u2019s new End TB Strategy in the post-2015 era of the Sustainable Development Goals.","volume":"385","author":"K L\u00f6nnroth","year":"2015","journal-title":"Lancet"},{"issue":"suppl_6","key":"pone.0257242.ref003","doi-asserted-by":"crossref","first-page":"S654","DOI":"10.1093\/infdis\/jix320","article-title":"Designing and evaluating interventions to halt the transmission of tuberculosis","volume":"216","author":"DW Dowdy","year":"2017","journal-title":"The Journal of infectious diseases"},{"issue":"4","key":"pone.0257242.ref004","doi-asserted-by":"crossref","first-page":"e94465","DOI":"10.1371\/journal.pone.0094465","article-title":"A multi-site evaluation of innovative approaches to increase tuberculosis case notification: summary results","volume":"9","author":"J Creswell","year":"2014","journal-title":"PLoS One"},{"issue":"1","key":"pone.0257242.ref005","first-page":"1","article-title":"A comparative impact evaluation of two human resource models for community-based active tuberculosis case finding in Ho Chi Minh City, Viet Nam.","volume":"20","author":"LNQ Vo","year":"2020","journal-title":"BMC Public Health"},{"issue":"3","key":"pone.0257242.ref006","doi-asserted-by":"crossref","first-page":"143","DOI":"10.3390\/tropicalmed5030143","article-title":"Enhanced private sector engagement for tuberculosis diagnosis and reporting through an intermediary agency in Ho Chi Minh City, Viet Nam.","volume":"5","author":"LNQ Vo","year":"2020","journal-title":"Tropical Medicine and Infectious Disease"},{"issue":"1","key":"pone.0257242.ref007","first-page":"1","article-title":"Evaluating the yield of systematic screening for tuberculosis among three priority groups in Ho Chi Minh City, Viet Nam.","volume":"9","author":"LNQ Vo","year":"2020","journal-title":"Infectious diseases of poverty"},{"issue":"6","key":"pone.0257242.ref008","doi-asserted-by":"crossref","first-page":"e036285","DOI":"10.1136\/bmjopen-2019-036285","article-title":"\u2018Power plays plus push\u2019: experts\u2019 insights into the development and implementation of active tuberculosis case-finding policies globally, a qualitative study.","volume":"10","author":"O Biermann","year":"2020","journal-title":"BMJ Open"},{"issue":"1","key":"pone.0257242.ref009","doi-asserted-by":"crossref","first-page":"134","DOI":"10.1186\/s12879-020-4865-7","article-title":"Tuberculosis among economic migrants: a cross-sectional study of the risk of poor treatment outcomes and impact of a treatment adherence intervention among temporary residents in an urban district in Ho Chi Minh City, Viet Nam.","volume":"20","author":"LNQ Vo","year":"2020","journal-title":"BMC infectious diseases"},{"key":"pone.0257242.ref010","volume-title":"Developing Feasible, Locally Appropriate Socioeconomic Support for TB-Affected Households in Nepal.","author":"B Rai","year":"2020"},{"issue":"4","key":"pone.0257242.ref011","doi-asserted-by":"crossref","first-page":"185","DOI":"10.3390\/tropicalmed5040185","article-title":"An Evaluation of Programmatic Community-Based Chest X-ray Screening for Tuberculosis in Ho Chi Minh City","volume":"5","author":"LH Nguyen","year":"2020","journal-title":"Vietnam. Tropical Medicine and Infectious Disease"},{"key":"pone.0257242.ref012","first-page":"czaa156","article-title":"How to reduce household costs for people with tuberculosis: a longitudinal costing survey in Nepal.","author":"SC Gurung","year":"2020","journal-title":"Health Policy and Planning"},{"issue":"19","key":"pone.0257242.ref013","doi-asserted-by":"crossref","first-page":"19","DOI":"10.12688\/wellcomeopenres.15677.2","article-title":"Research protocol for a mixed-methods study to characterise and address the socioeconomic impact of accessing TB diagnosis and care in Nepal.","volume":"5","author":"K Dixit","year":"2020","journal-title":"Wellcome Open Research"},{"issue":"1","key":"pone.0257242.ref014","doi-asserted-by":"crossref","first-page":"159","DOI":"10.1093\/cid\/ciy938","article-title":"The importance of heterogeneity to the epidemiology of tuberculosis","volume":"69","author":"JM Trauer","year":"2019","journal-title":"Clinical infectious diseases"},{"issue":"1","key":"pone.0257242.ref015","first-page":"1","article-title":"Introducing risk inequality metrics in tuberculosis policy development","volume":"10","author":"MGM Gomes","year":"2019","journal-title":"Nature communications"},{"issue":"4","key":"pone.0257242.ref016","doi-asserted-by":"crossref","first-page":"432","DOI":"10.5588\/ijtld.12.0743","article-title":"The benefits to communities and individuals of screening for active tuberculosis disease: a systematic review [State of the art series. 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