biostudies-literatureMayfield HJBill & Melinda Gates FoundationAustralian National Health and Medical Research Council311https://www.ebi.ac.uk/biostudies/studies/S-EPMC11680324biostudies-literatureUnknown9(12)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, 7-9 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 5-9-year-olds and ≥10-year-olds. We surveyed 30 randomly selected and five purposefully selected primary sampling units (PSUs) in Samoa in 2018 (1-3 months post-triple-drug MDA) and, again, in 2019. In each PSU, we conducted a community survey of 15-20 households and a convenience survey of 5-9-year-old children. A finger-prick blood sample was collected froTropical medicine and infectious diseaseEpidemiology of Lymphatic Filariasis Antigen and Microfilaria in Samoa, 2019: 7-9 Months Post Triple-Drug Mass Administration.PMC11680324OPP1190754APP1158469Sartorius BGass KGraves PMLau CLMayfield HJSheridan SKearns THedtke SMNaseri TThomsen RLawford HfalseEpidemiology of Lymphatic Filariasis Antigen and Microfilaria in Samoa, 2019: 7-9 Months Post Triple-Drug Mass Administration.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, 7-9 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 5-9-year-olds and ≥10-year-olds. We surveyed 30 randomly selected and five purposefully selected primary sampling units (PSUs) in Samoa in 2018 (1-3 months post-triple-drug MDA) and, again, in 2019. In each PSU, we conducted a community survey of 15-20 households and a convenience survey of 5-9-year-old children. A finger-prick blood sample was collected fro2024-01-01T00:00:00Z2024 Dec2025-04-04T02:36:06.643Z2025-04-04T02:36:06.643ZS-EPMC116803243972883810.3390/tropicalmed9120311