{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T00:55:31Z","timestamp":1791939331002,"version":"4.3.4"},"reference-count":38,"publisher":"BMJ","issue":"1","license":[{"start":{"date-parts":[[2026,1,30]],"date-time":"2026-01-30T00:00:00Z","timestamp":1769731200000},"content-version":"unspecified","delay-in-days":29,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000865","name":"Bill and Melinda Gates Foundation","doi-asserted-by":"publisher","award":["INV-078340"],"award-info":[{"award-number":["INV-078340"]}],"id":[{"id":"10.13039\/100000865","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open"],"accepted":{"date-parts":[[2026,1,20]]},"published-print":{"date-parts":[[2026,1]]},"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>India targets to eliminate lymphatic filariasis (LF) in alignment with the global goals. By 2024, 106 out of a total of 345 endemic districts have passed all three serial transmission assessment surveys (TAS) and are under post-mass drug administration (MDA) surveillance for a variable period. However, the current epidemiological situation of LF is not known in these districts. With increased mobility of population from the endemic districts currently under MDA to these post-MDA areas, resurgence of LF in these areas cannot be ruled out. Therefore, a study is planned to understand the current LF status in areas under post-MDA surveillance with the following objectives: (1) To assess the epidemiological situation of LF in terms of human and vector infection prevalence in selected evaluation units (EUs) under different durations of post-MDA phase and (2) to estimate the filarial infection (in terms of filarial antigen and microfilaria) among migrants (from endemic districts) in these EUs.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods and analysis<\/jats:title>\n                    <jats:p>This cross-sectional study will measure the filarial infection in (1) adult population aged \u226520 years (following the WHO 2025 protocol for monitoring and evaluation of MDA) among general population (n=3150 per EU), (2) migrant population (aged 2 years and above) in the post-MDA area originating from endemic areas (n=1000 per EU) and (3) vectors (n=7500 per EU) using molecular xenomonitoring (MX) to confirm sustenance of transmission interruption or identify any potential risk of resurgence in three EUs under post-MDA phase. In one MDA-naive EU that shares borders with endemic districts, filarial infection status will be assessed in (1) school children aged 9\u201314 years (as per WHO mini-TAS protocol, n=480), (2) migrants (aged 2 years and above) from endemic areas (n=1000) and (3) vectors (n=7500). EU-wide prevalence of microfilaria, circulating filarial antigen and vector infection rates with 95% CIs will be estimated. Multivariate logistic regression analysis will be carried out to find factors associated with LF positivity. In addition, knowledge, attitude and practice surveys will also be conducted among the adult migrants (n=1000 per EU). Thirty in-depth interviews will be conducted among the migrants, local community and health workers (in each EU) and the results will be suitably analysed and triangulated. The study results will enable the national programme to confirm sustenance of transmission interruption or assist in taking a decision to reinitiate MDA in these areas under post-MDA surveillance. It will also enable devising specific strategies to treat migrants.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Ethics and dissemination<\/jats:title>\n                    <jats:p>This study has been approved by the institutional ethics committee (IHEC 03-0824\/N\/F). A workshop will be held with all stakeholders to disseminate the study findings.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjopen-2025-116111","type":"journal-article","created":{"date-parts":[[2026,1,30]],"date-time":"2026-01-30T11:30:19Z","timestamp":1769772619000},"page":"e116111","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":3,"title":["Cross-sectional epidemiological assessment of lymphatic filariasis situation in areas under post-mass drug administration surveillance and the associated risk of transmission in the context of migrants in India: a study protocol"],"prefix":"10.1136","volume":"16","author":[{"given":"Adinarayanan","family":"Srividya","sequence":"first","affiliation":[{"name":"ICMR - Vector Control Research Centre, Puducherry, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3359-3039","authenticated-orcid":false,"given":"Raja J","family":"Dinesh","sequence":"additional","affiliation":[{"name":"ICMR - Vector Control Research Centre, Puducherry, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4503-4867","authenticated-orcid":false,"given":"Muhammed Jabir","family":"M M","sequence":"additional","affiliation":[{"name":"ICMR - Vector Control Research Centre, Puducherry, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Manikandan","family":"Kishanthini","sequence":"additional","affiliation":[{"name":"ICMR - Vector Control Research Centre, Puducherry, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vishal","family":"Dogra","sequence":"additional","affiliation":[{"name":"Gates Foundation, New Delhi, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bhupendra","family":"Tripathi","sequence":"additional","affiliation":[{"name":"Infectious Diseases & Vaccine Delivery, Gates Foundation, New Delhi, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rinku","family":"Sharma","sequence":"additional","affiliation":[{"name":"National Center for Vector Borne Diseases Control, Government of India Ministry of Health & Family Welfare, New Delhi, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tanu","family":"Jain","sequence":"additional","affiliation":[{"name":"National Center for Vector Borne Diseases Control, Government of India Ministry of Health & Family Welfare, New Delhi, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0932-0935","authenticated-orcid":false,"given":"Manju","family":"Rahi","sequence":"additional","affiliation":[{"name":"ICMR - Vector Control Research Centre, Puducherry, India"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2026,1,30]]},"reference":[{"key":"2026013003301238000_16.1.e116111.1","unstructured":"WHO . Monitoring and Epidemiological Assessment of Mass Drug Administration in the Global Programme to Eliminate Lymphatic Filariasis: A Manual for National Elimination Programmes. 2nd edn. 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Post-validation surveillance for lymphatic filariasis. 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