{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,5]],"date-time":"2026-10-05T19:10:28Z","timestamp":1791227428673,"version":"4.1.0"},"update-to":[{"DOI":"10.1371\/journal.pntd.0010262","type":"new_version","label":"New version","source":"publisher","updated":{"date-parts":[[2022,4,7]],"date-time":"2022-04-07T00:00:00Z","timestamp":1649289600000}}],"reference-count":51,"publisher":"Public Library of Science (PLoS)","issue":"3","license":[{"start":{"date-parts":[[2022,3,28]],"date-time":"2022-03-28T00:00:00Z","timestamp":1648425600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000865","name":"Bill and Melinda Gates Foundation","doi-asserted-by":"publisher","award":["OPP 1053230"],"award-info":[{"award-number":["OPP 1053230"]}],"id":[{"id":"10.13039\/100000865","id-type":"DOI","asserted-by":"publisher"}]},{"name":"United Kingdom Department for International Development"},{"DOI":"10.13039\/100000200","name":"United States Agency for International Development","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100000200","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Westpac Research Fellowship"},{"name":"Australian National Health and Medical Research Council Fellowships","award":["APP1109035 and APP1158469"],"award-info":[{"award-number":["APP1109035 and 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>American Samoa completed seven rounds of mass drug administration from 2000\u20132006 as part of the Global Programme to Eliminate Lymphatic Filariasis (LF). However, resurgence was confirmed in 2016 through WHO-recommended school-based transmission assessment survey and a community-based survey. This paper uses data from the 2016 community survey to compare different spatial and non-spatial methods to characterise clustering and hotspots of LF.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec002\">\n<jats:title>Method<\/jats:title>\n<jats:p>Non-spatial clustering of infection markers (antigen [Ag], microfilaraemia [Mf], and antibodies (Ab [Wb123, Bm14, Bm33]) was assessed using intra-cluster correlation coefficients (ICC) at household and village levels. Spatial dependence, clustering and hotspots were examined using semivariograms, Kulldorf\u2019s scan statistic and Getis-Ord Gi* statistics based on locations of surveyed households.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec003\">\n<jats:title>Results<\/jats:title>\n<jats:p>The survey included 2671 persons (750 households, 730 unique locations in 30 villages). ICCs were higher at household (0.20\u20130.69) than village levels (0.10\u20130.30) for all infection markers. Semivariograms identified significant spatial dependency for all markers (range 207\u2013562 metres). Using Kulldorff\u2019s scan statistic, significant spatial clustering was observed in two previously known locations of ongoing transmission: for all markers in Fagali\u2019i and all Abs in Vaitogi. Getis-Ord Gi* statistic identified hotspots of all markers in Fagali\u2019i, Vaitogi, and Pago Pago-Anua areas. A hotspot of Ag and Wb123 Ab was identified around the villages of Nua-Seetaga-Asili. Bm14 and Bm33 Ab hotspots were seen in Maleimi and Vaitogi-Ili\u2019ili-Tafuna.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec004\">\n<jats:title>Conclusion<\/jats:title>\n<jats:p>Our study demonstrated the utility of different non-spatial and spatial methods for investigating clustering and hotspots, the benefits of using multiple infection markers, and the value of triangulating results between methods.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pntd.0010262","type":"journal-article","created":{"date-parts":[[2022,3,28]],"date-time":"2022-03-28T17:29:36Z","timestamp":1648488576000},"page":"e0010262","update-policy":"https:\/\/doi.org\/10.1371\/journal.pntd.corrections_policy","source":"Crossref","is-referenced-by-count":14,"title":["Lymphatic filariasis in 2016 in American Samoa: Identifying clustering and hotspots using non-spatial and three spatial analytical 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