{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,19]],"date-time":"2026-10-19T16:43:37Z","timestamp":1792428217680,"version":"4.5.0"},"update-to":[{"DOI":"10.1371\/journal.pntd.0012331","type":"new_version","label":"New version","source":"publisher","updated":{"date-parts":[[2024,7,24]],"date-time":"2024-07-24T00:00:00Z","timestamp":1721779200000}}],"reference-count":32,"publisher":"Public Library of Science (PLoS)","issue":"7","license":[{"start":{"date-parts":[[2024,7,12]],"date-time":"2024-07-12T00:00:00Z","timestamp":1720742400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"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>Soil-transmitted helminthiases (STHs) are common in tropical and subtropical regions. Southern Thailand experiences an extended rainy season, leading to persistently moist soil. This condition supports the life cycle of STHs, hindering effective control due to reinfection and low drug efficacy. We implemented a novel STH control strategy during the dry season aimed at decreasing reinfection rates without enhancing sanitation or hygiene practices. However, there were unexpected, prolonged droughts linked to El Ni\u00f1o events from 2014 to 2016. Additionally, we assessed the effects of these drought conditions on further control measures without the use of anthelmintics.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec002\">\n<jats:title>Methodology\/Principal findings<\/jats:title>\n<jats:p>A longitudinal study was conducted from 2012 to 2016. Stool samples collected from 299 participants were analyzed using the Kato-Katz and agar plate culture methods. Participants who tested positive for STHs received a single 400 mg dose of albendazole. The efficacy of the treatment was evaluated three weeks later. To confirm the control measures were implemented during the dry season, we monitored the number of rainy days following albendazole treatment for 52 days, of which 38 were without rain. Follow-up stool examinations were carried out in 2013 and 2016, with no additional doses of albendazole administered. Rainfall and rainy day data, which served as indicators of unexpected droughts due to El Ni\u00f1o, were collected from the nearest local meteorological stations. Before the drought, there was a decrease in STH prevalence in 2013\u2014except for trichuriasis\u2014attributable to the dry season control efforts. Despite these efforts, STH prevalence remained high. Remarkably, in 2016, following the drought period, the prevalence of trichuriasis, which had not changed previously, spontaneously declined without further albendazole treatment compared to 2013.<\/jats:p>\n<jats:p>Furthermore, the prevalence of strongyloidiasis remained unchanged likely due to its low susceptibility to drought conditions, as it can reproduce within hosts. Conversely, the prevalence of other STHs consistently declined. The drought and possible improvements in sanitation and hygiene practices contributed to this decrease by reducing rates of reinfection and new infection and by increasing the natural cure rate. Additionally, some participants infected with hookworms or <jats:italic>Trichuris<\/jats:italic> who were not cured by albendazole experienced natural remission.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec003\">\n<jats:title>Conclusions\/Significance<\/jats:title>\n<jats:p>Control measures implemented during the dry season, combined with a 14-month-long drought induced by the El Ni\u00f1o event of 2014\u20132016, and some improvements in sanitation and hygiene practices, contributed to a decrease in both the prevalence and intensity of STHs, except for <jats:italic>S<\/jats:italic>. <jats:italic>stercoralis<\/jats:italic>. Over time, <jats:italic>S<\/jats:italic>. <jats:italic>stercoralis<\/jats:italic> is likely to become the predominant species among the STHs.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pntd.0012331","type":"journal-article","created":{"date-parts":[[2024,7,12]],"date-time":"2024-07-12T17:39:13Z","timestamp":1720805953000},"page":"e0012331","update-policy":"https:\/\/doi.org\/10.1371\/journal.pntd.corrections_policy","source":"Crossref","is-referenced-by-count":6,"title":["The enhancive effect of the 2014\u20132016 El Ni\u00f1o-induced drought on the control of soil-transmitted helminthiases without anthelmintics: A longitudinal 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and southern Thailand","volume":"51","author":"I Phosuk","year":"2013","journal-title":"Korean J Parasitol"},{"issue":"12","key":"pntd.0012331.ref005","doi-asserted-by":"crossref","first-page":"547","DOI":"10.1016\/j.pt.2003.10.002","article-title":"Soil-transmitted helminth infections: updating the global picture","volume":"19","author":"NR de Silva","year":"2003","journal-title":"Trends Parasitol"},{"key":"pntd.0012331.ref006","doi-asserted-by":"crossref","first-page":"197","DOI":"10.1016\/S0065-308X(04)58004-1","article-title":"Human hookworm infection in the 21st century.","volume":"58","author":"S Brooker","year":"2004","journal-title":"Adv Parasitol."},{"issue":"7","key":"pntd.0012331.ref007","doi-asserted-by":"crossref","first-page":"2817","DOI":"10.1007\/s00436-016-5031-4","article-title":"Restoration of hookworm egg development after prolonged storage in stool suspension","volume":"115","author":"P Na-Ek","year":"2016","journal-title":"Parasitol 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Climate Prediction Center","year":"2023"},{"issue":"1","key":"pntd.0012331.ref029","first-page":"1118","article-title":"Prevalence of intestinal parasitic infections and associated risk factors for hookworm infections among primary schoolchildren in rural areas of Nakhon Si Thammarat, southern Thailand.","volume":"18","author":"C Punsawad","year":"2018","journal-title":"Sep"},{"issue":"1","key":"pntd.0012331.ref030","doi-asserted-by":"crossref","first-page":"564","DOI":"10.1186\/s12889-017-4486-2","article-title":"Prevalence of intestinal parasitic infection and associated risk factors among village health volunteers in rural communities of southern Thailand.","volume":"17","author":"C Punsawad","year":"2017","journal-title":"BMC Public Health."},{"issue":"1","key":"pntd.0012331.ref031","doi-asserted-by":"crossref","first-page":"1882","DOI":"10.1186\/s12889-020-09986-7","article-title":"Prevalence of soil-transmitted helminth infections and associated risk factors among elderly individuals living in rural areas of southern Thailand.","volume":"20","author":"R Kache","year":"2020","journal-title":"BMC Public Health."},{"issue":"8","key":"pntd.0012331.ref032","doi-asserted-by":"crossref","first-page":"397","DOI":"10.1093\/trstmh\/try068","article-title":"Complex interactions in soil-transmitted helminth co-infections from a cross-sectional study in Sri Lanka","volume":"112","author":"HC Lepper","year":"2018","journal-title":"Trans R Soc Trop Med Hyg"}],"updated-by":[{"DOI":"10.1371\/journal.pntd.0012331","type":"new_version","label":"New version","source":"publisher","updated":{"date-parts":[[2024,7,24]],"date-time":"2024-07-24T00:00:00Z","timestamp":1721779200000}}],"container-title":["PLOS Neglected Tropical Diseases"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pntd.0012331","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,7,24]],"date-time":"2024-07-24T17:53:54Z","timestamp":1721843634000},"score":1,"resource":{"primary":{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pntd.0012331"}},"subtitle":[],"editor":[{"given":"Qu","family":"Cheng","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"editor"}]}],"short-title":[],"issued":{"date-parts":[[2024,7,12]]},"references-count":32,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2024,7,12]]}},"URL":"https:\/\/doi.org\/10.1371\/journal.pntd.0012331","relation":{"new_version":[{"id-type":"doi","id":"10.1371\/journal.pntd.0012331","asserted-by":"object"}]},"ISSN":["1935-2735"],"issn-type":[{"value":"1935-2735","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,7,12]]}}}