{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,16]],"date-time":"2026-10-16T06:34:30Z","timestamp":1792132470932,"version":"4.4.0"},"reference-count":28,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2021,4,1]],"date-time":"2021-04-01T00:00:00Z","timestamp":1617235200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Bill and Melinda Gates Foundation - Task Force for Global Health","award":["OPP1053230"],"award-info":[{"award-number":["OPP1053230"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["TropicalMed"],"abstract":"<jats:p>Following the first triple-drug mass drug administration (MDA) for lymphatic filariasis in Samoa in 2018, unexpected persistence of microfilaria (Mf) positivity in 18 (15%) of 121 antigen-positive persons was observed in a nationwide household survey 1\u20132 months later. Of the 18 Mf positive persons, 14 reported taking the MDA, raising concerns about MDA efficacy. In 2019, 5\u20136 months after the 2018 survey, a monitored treatment study was done to evaluate directly observed weight-based treatment in these Mf positive individuals. Mf presence and density were assessed before and 7 days after treatment, using 1 mL membrane filtered venous blood, and 60 uL thick blood films on slides prepared from venous or fingerprick blood. All 14 participants were still Mf positive on filters from venous blood pre-treatment samples, but two were negative by slide made from the same samples. Mf were cleared completely by day 7 in 12 of 13 participants followed up, and by day 30 in the remaining participant. Filtered blood using EDTA samples (to reduce clumping of Mf) is preferred over slides alone for improving the likelihood of detecting Mf and estimating their density. The triple-drug MDA strategy was effective at clearing Mf when given and taken at the correct dose.<\/jats:p>","DOI":"10.3390\/tropicalmed6020044","type":"journal-article","created":{"date-parts":[[2021,4,1]],"date-time":"2021-04-01T10:44:01Z","timestamp":1617273841000},"page":"44","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Triple-Drug Treatment Is Effective for Lymphatic Filariasis Microfilaria Clearance in Samoa"],"prefix":"10.3390","volume":"6","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5215-3901","authenticated-orcid":false,"given":"Patricia M.","family":"Graves","sequence":"first","affiliation":[{"name":"College of Public Health, Medical and Veterinary Sciences, James Cook University, Cairns, QLD 4870 and Townsville, QLD 4811, 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"}]},{"given":"Jessica","family":"Scott","sequence":"additional","affiliation":[{"name":"College of Public Health, Medical and Veterinary Sciences, James Cook University, Cairns, QLD 4870 and Townsville, QLD 4811, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Filipina","family":"Amosa-Lei Sam","sequence":"additional","affiliation":[{"name":"School of Medicine, National University of Samoa, Apia, Samoa"}],"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"}]},{"given":"Christopher L.","family":"King","sequence":"additional","affiliation":[{"name":"Center for Global Health, School of Medicine and Veterans Affairs Administration, Case Western Reserve University, Cleveland, OH 44106, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8288-4169","authenticated-orcid":false,"given":"Colleen L.","family":"Lau","sequence":"additional","affiliation":[{"name":"School of Public Health, The University of Queensland, Brisbane, QLD 4006, Australia"},{"name":"Research School of Population Health, The Australian National University, Canberra, ACT 2601, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Ramaiah, K.D., and Ottesen, E.A. 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