{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,16]],"date-time":"2026-10-16T06:35:11Z","timestamp":1792132511464,"version":"4.4.0"},"reference-count":31,"publisher":"Public Library of Science (PLoS)","issue":"6","license":[{"start":{"date-parts":[[2024,6,27]],"date-time":"2024-06-27T00:00:00Z","timestamp":1719446400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Taskforce for Global Health","award":["OPP1190754"],"award-info":[{"award-number":["OPP1190754"]}]},{"name":"Australian National Health and Medical Research Council","award":["APP1158469"],"award-info":[{"award-number":["APP1158469"]}]}],"content-domain":{"domain":["www.plosntds.org"],"crossmark-restriction":false},"short-container-title":["PLoS Negl Trop Dis"],"abstract":"<jats:sec id=\"sec001\">\n<jats:title>Background<\/jats:title>\n<jats:p>Lymphatic filariasis (LF) remains a significant global issue. To eliminate LF as a public health problem, the World Health Organization (WHO) recommends multiple rounds of mass drug administration (MDA). In certain scenarios, including when elimination targets have not been met with two-drug MDA, triple-drug MDA (using ivermectin, diethylcarbamazine and albendazole) is recommended. In this study, we report on antigen (Ag) and microfilaria (Mf) prevalence in eight primary sampling units (PSUs) in Samoa 4.5 years after one round of triple-drug MDA.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec002\">\n<jats:title>Methodology<\/jats:title>\n<jats:p>In 2023, community surveys were conducted in eight PSUs that had been surveyed previously in 2018 (between 1.5 and 3.5 months post triple-drug MDA) and 2019 (six to eight-months post triple-drug MDA). Fifteen houses were randomly selected in each PSU with household members aged \u2265 5 years invited to participate. Blood samples were tested for Ag and Mf.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec003\">\n<jats:title>Principal findings<\/jats:title>\n<jats:p>Ag-positive participants were observed in six of the eight PSUs, and Ag prevalence was significantly above the 1% threshold in four PSUs. The presence of Mf-positive participants in five PSUs confirms the presence of residual active infections.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec004\">\n<jats:title>Conclusions\/Significance<\/jats:title>\n<jats:p>This study provides evidence of persistent LF transmission in Samoa 4.5 years after one round of triple-drug MDA, confirming that one round was insufficient for interruption of transmission in this setting. Our findings highlight the negative impact of delaying MDA rounds, for example, due to public health emergencies.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pntd.0012236","type":"journal-article","created":{"date-parts":[[2024,6,27]],"date-time":"2024-06-27T17:51:24Z","timestamp":1719510684000},"page":"e0012236","update-policy":"https:\/\/doi.org\/10.1371\/journal.pntd.corrections_policy","source":"Crossref","is-referenced-by-count":17,"title":["Ongoing transmission of lymphatic filariasis in Samoa 4.5 years after one round of triple-drug mass drug administration"],"prefix":"10.1371","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3462-4324","authenticated-orcid":true,"given":"Helen J.","family":"Mayfield","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Benn","family":"Sartorius","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarah","family":"Sheridan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maddison","family":"Howlett","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Beatris Mario","family":"Martin","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert","family":"Thomsen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rossana","family":"Tofaeono-Pifeleti","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Satupaitea","family":"Viali","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Patricia M.","family":"Graves","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Colleen L.","family":"Lau","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2024,6,27]]},"reference":[{"issue":"1","key":"pntd.0012236.ref001","doi-asserted-by":"crossref","first-page":"181","DOI":"10.1186\/s13071-022-05268-w","article-title":"A refined and updated health impact assessment of the Global Programme to Eliminate Lymphatic Filariasis (2000\u20132020).","volume":"15","author":"HC Turner","year":"2022","journal-title":"Parasites & Vectors."},{"key":"pntd.0012236.ref002","unstructured":"World Health Organisation. Weekly epidemiological record, 13 October 2023. 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Guideline: Alternative Mass Drug Administrations to Eliminate Lymphatic Filariasis Geneva, Switzerland:2017 [19\/09\/2023]. 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