{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T15:43:37Z","timestamp":1787586217465,"version":"build-2736575974"},"update-to":[{"DOI":"10.1371\/journal.pntd.0010506","type":"new_version","label":"New version","source":"publisher","updated":{"date-parts":[[2022,6,24]],"date-time":"2022-06-24T00:00:00Z","timestamp":1656028800000}}],"reference-count":48,"publisher":"Public Library of Science (PLoS)","issue":"6","license":[{"start":{"date-parts":[[2022,6,13]],"date-time":"2022-06-13T00:00:00Z","timestamp":1655078400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Medical Research Council","award":["MR\/N013638\/1"],"award-info":[{"award-number":["MR\/N013638\/1"]}]},{"name":"Royal Society Dorothy Hodgkin Fellowship"},{"name":"Wellcome Trust and the Royal Society","award":["206250\/Z\/17\/Z"],"award-info":[{"award-number":["206250\/Z\/17\/Z"]}]},{"name":"Australian National Health and Medical Research Council Fellowship","award":["1109035"],"award-info":[{"award-number":["1109035"]}]},{"name":"Australian National Health and Medical Research Council Fellowship","award":["1193826"],"award-info":[{"award-number":["1193826"]}]}],"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>Leptospirosis is a zoonotic disease prevalent throughout the world, but with particularly high burden in Oceania (including the Pacific Island Countries and Territories). Leptospirosis is endemic in Fiji, with outbreaks often occurring following heavy rainfall and flooding. As a result of non-specific clinical manifestation and diagnostic challenges, cases are often misdiagnosed or under-ascertained. Furthermore, little is known about the duration of persistence of antibodies to leptospirosis, which has important clinical and epidemiological implications.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Methodology and principal findings<\/jats:title>\n                    <jats:p>Using the results from a serosurvey conducted in Fiji in 2013, we fitted serocatalytic models to estimate the duration of antibody positivity and the force of infection (FOI, the rate at which susceptible individuals acquire infection or seroconversion), whilst accounting for seroreversion. Additionally, we estimated the most likely timing of infection.<\/jats:p>\n                    <jats:p>Using the reverse catalytic model, we estimated the duration of antibody persistence to be 8.33 years (4.76\u201312.50; assuming constant FOI) and 7.25 years (3.36\u201311.36; assuming time-varying FOI), which is longer than previous estimates. Using population age-structured seroprevalence data alone, we were not able to distinguish between these two models. However, by bringing in additional longitudinal data on antibody kinetics we were able to estimate the most likely time of infection, lending support to the time-varying FOI model. We found that most individuals who were antibody-positive in the 2013 serosurvey were likely to have been infected within the previous two years, and this finding is consistent with surveillance data showing high numbers of cases reported in 2012 and 2013.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>\n                      This is the first study to use serocatalytic models to estimate the FOI and seroreversion rate for\n                      <jats:italic>Leptospira<\/jats:italic>\n                      infection. As well as providing an estimate for the duration of antibody positivity, we also present a novel method to estimate the most likely time of infection from seroprevalence data. These approaches can allow for richer, longitudinal information to be inferred from cross-sectional studies, and could be applied to other endemic diseases where antibody waning occurs.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pntd.0010506","type":"journal-article","created":{"date-parts":[[2022,6,13]],"date-time":"2022-06-13T13:50:31Z","timestamp":1655128231000},"page":"e0010506","update-policy":"https:\/\/doi.org\/10.1371\/journal.pntd.corrections_policy","source":"Crossref","is-referenced-by-count":24,"title":["Estimating the duration of antibody positivity and likely time of Leptospira infection using data from a cross-sectional serological study in Fiji"],"prefix":"10.1371","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4993-2795","authenticated-orcid":true,"given":"Eleanor M.","family":"Rees","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Colleen L.","family":"Lau","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mike","family":"Kama","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Simon","family":"Reid","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rachel","family":"Lowe","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adam J.","family":"Kucharski","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2022,6,13]]},"reference":[{"key":"pntd.0010506.ref001","article-title":"Global Morbidity and Mortality of Leptospirosis: A Systematic Review","author":"F Costa","year":"2015","journal-title":"PLoS Neglected Tropical Diseases"},{"key":"pntd.0010506.ref002","doi-asserted-by":"crossref","first-page":"99","DOI":"10.1007\/978-3-662-45059-8_6","volume-title":"Leptospira and Leptospirosis","author":"WA Ellis","year":"2015"},{"key":"pntd.0010506.ref003","volume":"12","author":"V Guernier","year":"2018","journal-title":"A systematic review of human and animal leptospirosis in the Pacific Islands reveals pathogen and reservoir diversity"},{"key":"pntd.0010506.ref004","volume-title":"The control of neglected zoonotic diseases: from advocacy to action: report of the fourth international meeting held at WHO Headquarters, Geneva, Switzerland, 19\u201320 November 2014","author":"World Health Organization","year":"2015"},{"key":"pntd.0010506.ref005","article-title":"Climate change, flooding, urbanisation and leptospirosis: Fuelling the fire?","author":"CL Lau","year":"2010","journal-title":"Transactions of the Royal Society of Tropical Medicine and Hygiene"},{"key":"pntd.0010506.ref006","doi-asserted-by":"crossref","first-page":"296","DOI":"10.1128\/CMR.14.2.296-326.2001","article-title":"Leptospirosis","volume":"14","author":"PN Levett","year":"2001","journal-title":"Clinical Microbiology Reviews"},{"key":"pntd.0010506.ref007","volume-title":"MM-TL, undefined. 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