{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,7]],"date-time":"2026-11-07T00:00:45Z","timestamp":1794009645705,"version":"4.8.0"},"reference-count":27,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2024,12,23]],"date-time":"2024-12-23T00:00:00Z","timestamp":1734912000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Coalition for Operational Research on Neglected Tropical Diseases","award":["OPP1053230"],"award-info":[{"award-number":["OPP1053230"]}]},{"name":"Coalition for Operational Research on Neglected Tropical Diseases","award":["1109035"],"award-info":[{"award-number":["1109035"]}]},{"name":"Coalition for Operational Research on Neglected Tropical Diseases","award":["1193826"],"award-info":[{"award-number":["1193826"]}]},{"name":"Bill &amp; Melinda Gates Foundation","award":["OPP1053230"],"award-info":[{"award-number":["OPP1053230"]}]},{"name":"Bill &amp; Melinda Gates Foundation","award":["1109035"],"award-info":[{"award-number":["1109035"]}]},{"name":"Bill &amp; Melinda Gates Foundation","award":["1193826"],"award-info":[{"award-number":["1193826"]}]},{"name":"Australian National Health and Medical Research Council","award":["OPP1053230"],"award-info":[{"award-number":["OPP1053230"]}]},{"name":"Australian National Health and Medical Research Council","award":["1109035"],"award-info":[{"award-number":["1109035"]}]},{"name":"Australian National Health and Medical Research Council","award":["1193826"],"award-info":[{"award-number":["1193826"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["TropicalMed"],"abstract":"<jats:p>The elimination of lymphatic filariasis (LF) as a public health problem remains an ongoing challenge in the Pacific region. This study reports on antigen (Ag) and microfilaria (Mf) prevalence in Samoa in 2019, 7\u20139 months after the completion of the first round of triple-drug mass drug administration (MDA). It evaluates the effectiveness of the intervention for reducing Ag prevalence to below a 2% threshold, and how this differs between 5\u20139-year-olds and \u226510-year-olds. We surveyed 30 randomly selected and five purposefully selected primary sampling units (PSUs) in Samoa in 2018 (1\u20133 months post-triple-drug MDA) and, again, in 2019. In each PSU, we conducted a community survey of 15\u201320 households and a convenience survey of 5\u20139-year-old children. A finger-prick blood sample was collected from all participants to test for Ag and Mf. Demographic details were also collected. There was no significant change in adjusted Ag prevalence in the 30 randomly selected PSUs between 2018 (3.9% [95% CI: 2.7\u20135.6%]) and 2019 (4.1% [95% CI 2.7\u20135.9%]). Significantly higher Ag prevalence was observed in participants aged \u226510 years (4.6%, 95% CIs 3.0\u20136.7%) compared to 5\u20139-year-olds (1.1%, 95% CIs 0.5\u20132.2%), supporting existing evidence that post-MDA surveillance should not be based on Ag prevalence among 6\u20137-year-olds. A single round of triple-drug MDA was insufficient to break LF transmission in Samoa 7\u20139 months post-MDA.<\/jats:p>","DOI":"10.3390\/tropicalmed9120311","type":"journal-article","created":{"date-parts":[[2024,12,23]],"date-time":"2024-12-23T08:16:07Z","timestamp":1734941767000},"page":"311","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Epidemiology of Lymphatic Filariasis Antigen and Microfilaria in Samoa, 2019: 7\u20139 Months Post Triple-Drug Mass Drug Administration"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3462-4324","authenticated-orcid":false,"given":"Helen","family":"Mayfield","sequence":"first","affiliation":[{"name":"Centre for Clinical Research, The University of Queensland, Brisbane, QLD 4006, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Harriet","family":"Lawford","sequence":"additional","affiliation":[{"name":"Centre for Clinical Research, The University of Queensland, Brisbane, QLD 4006, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Benn","family":"Sartorius","sequence":"additional","affiliation":[{"name":"Centre for Clinical Research, The University of Queensland, Brisbane, QLD 4006, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5215-3901","authenticated-orcid":false,"given":"Patricia","family":"Graves","sequence":"additional","affiliation":[{"name":"College of Public Health, Medical and Veterinary Sciences, James Cook University, Cairns, QLD 4878, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarah","family":"Sheridan","sequence":"additional","affiliation":[{"name":"School of Public Health and Community Medicine, University of New South Wales, Sydney, NSW 2033, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0862-7572","authenticated-orcid":false,"given":"Therese","family":"Kearns","sequence":"additional","affiliation":[{"name":"Menzies School of Health Research, Charles Darwin University, Casuarina, NT 0810, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7499-7662","authenticated-orcid":false,"given":"Shannon","family":"Hedtke","sequence":"additional","affiliation":[{"name":"Department of Environment and Genetics, La Trobe University, Bundoora, VIC 3086, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2084-8039","authenticated-orcid":false,"given":"Katherine","family":"Gass","sequence":"additional","affiliation":[{"name":"Neglected Tropical Diseases Support Centre, The Task Force for Global Heath, Decatur, GA 30030, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Take","family":"Naseri","sequence":"additional","affiliation":[{"name":"Ministry of Health, Apia, Samoa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert","family":"Thomsen","sequence":"additional","affiliation":[{"name":"Ministry of Health, Apia, Samoa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8288-4169","authenticated-orcid":false,"given":"Colleen","family":"Lau","sequence":"additional","affiliation":[{"name":"Centre for Clinical Research, The University of Queensland, Brisbane, QLD 4006, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,12,23]]},"reference":[{"key":"ref_1","unstructured":"World Health Organization (2011). 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Dis., 6.","DOI":"10.20944\/preprints202103.0094.v1"}],"container-title":["Tropical Medicine and Infectious Disease"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2414-6366\/9\/12\/311\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T16:58:25Z","timestamp":1760115505000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2414-6366\/9\/12\/311"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,12,23]]},"references-count":27,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2024,12]]}},"alternative-id":["tropicalmed9120311"],"URL":"https:\/\/doi.org\/10.3390\/tropicalmed9120311","relation":{},"ISSN":["2414-6366"],"issn-type":[{"value":"2414-6366","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,12,23]]}}}