{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,31]],"date-time":"2025-12-31T11:07:35Z","timestamp":1767179255923,"version":"build-2238731810"},"update-to":[{"DOI":"10.1371\/journal.pntd.0009310","type":"new_version","label":"New version","source":"publisher","updated":{"date-parts":[[2021,4,22]],"date-time":"2021-04-22T00:00:00Z","timestamp":1619049600000}}],"reference-count":32,"publisher":"Public Library of Science (PLoS)","issue":"4","license":[{"start":{"date-parts":[[2021,4,5]],"date-time":"2021-04-05T00:00:00Z","timestamp":1617580800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Research Council","award":["ERC-2012-AdG-323180"],"award-info":[{"award-number":["ERC-2012-AdG-323180"]}]}],"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>\n                      The prevalence of\n                      <jats:italic>Schistosoma mansoni<\/jats:italic>\n                      infection is usually assessed by the Kato-Katz diagnostic technique. However, Kato-Katz thick smears have low sensitivity, especially for light infections. Egg count models fitted on individual level data can adjust for the infection intensity-dependent sensitivity and estimate the \u2018true\u2019 prevalence in a population. However, application of these models is complex and there is a need for adjustments that can be done without modeling expertise. This study provides estimates of the \u2018true\u2019\n                      <jats:italic>S. mansoni<\/jats:italic>\n                      prevalence from population summary measures of observed prevalence and infection intensity using extensive simulations parametrized with data from different settings in sub-Saharan Africa.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Methodology<\/jats:title>\n                    <jats:p>\n                      An individual-level egg count model was applied to Kato-Katz data to determine the\n                      <jats:italic>S. mansoni<\/jats:italic>\n                      infection intensity-dependent sensitivity for various sampling schemes. Observations in populations with varying forces of transmission were simulated, using standard assumptions about the distribution of worms and their mating behavior. Summary measures such as the geometric mean infection, arithmetic mean infection, and the observed prevalence of the simulations were calculated, and parametric statistical models fitted to the summary measures for each sampling scheme. For validation, the simulation-based estimates are compared with an observational dataset not used to inform the simulation.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Principal findings<\/jats:title>\n                    <jats:p>Overall, the sensitivity of Kato-Katz in a population varies according to the mean infection intensity. Using a parametric model, which takes into account different sampling schemes varying from single Kato-Katz to triplicate slides over three days, both geometric and arithmetic mean infection intensities improve estimation of sensitivity. The relation between observed and \u2018true\u2019 prevalence is remarkably linear and triplicate slides per day on three consecutive days ensure close to perfect sensitivity.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec004\">\n                    <jats:title>Conclusions\/significance<\/jats:title>\n                    <jats:p>\n                      Estimation of \u2018true\u2019\n                      <jats:italic>S. mansoni<\/jats:italic>\n                      prevalence is improved when taking into account geometric or arithmetic mean infection intensity in a population. We supply parametric functions and corresponding estimates of their parameters to calculate the \u2018true\u2019 prevalence for sampling schemes up to 3 days with triplicate Kato-Katz thick smears per day that allow estimation of the \u2018true\u2019 prevalence.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pntd.0009310","type":"journal-article","created":{"date-parts":[[2021,4,5]],"date-time":"2021-04-05T13:37:12Z","timestamp":1617629832000},"page":"e0009310","update-policy":"https:\/\/doi.org\/10.1371\/journal.pntd.corrections_policy","source":"Crossref","is-referenced-by-count":13,"title":["Estimating true prevalence of Schistosoma mansoni from population summary measures based on the Kato-Katz diagnostic technique"],"prefix":"10.1371","volume":"15","author":[{"given":"Oliver","family":"B\u00e4renbold","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Amadou","family":"Garba","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9381-8420","authenticated-orcid":true,"given":"Daniel G.","family":"Colley","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3866-2232","authenticated-orcid":true,"given":"Fiona M.","family":"Fleming","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rufin K.","family":"Assar\u00e9","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0624-2890","authenticated-orcid":true,"given":"Edridah M.","family":"Tukahebwa","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Biruck","family":"Kebede","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3626-6068","authenticated-orcid":true,"given":"Jean T.","family":"Coulibaly","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eli\u00e9zer K.","family":"N\u2019Goran","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7365-7650","authenticated-orcid":true,"given":"Louis-Albert","family":"Tchuem Tchuent\u00e9","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pauline","family":"Mwinzi","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"J\u00fcrg","family":"Utzinger","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4904-5352","authenticated-orcid":true,"given":"Penelope","family":"Vounatsou","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"340","published-online":{"date-parts":[[2021,4,5]]},"reference":[{"key":"pntd.0009310.ref001","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1038\/s41572-018-0013-8","article-title":"Schistosomiasis","volume":"4","author":"DP McManus","year":"2018","journal-title":"Nat Rev Dis Primers"},{"key":"pntd.0009310.ref002","doi-asserted-by":"crossref","first-page":"1859","DOI":"10.1016\/S0140-6736(18)32335-3","article-title":"Global, regional, and national disability-adjusted life-years (DALYs) for 359 diseases and injuries and healthy life expectancy (HALE) for 195 countries and territories, 1990-2017: a systematic analysis for the Global Burden of Disease Study 2017","volume":"392","author":"GBD 2017 DALYs and HALE Collaborators","year":"2018","journal-title":"Lancet"},{"key":"pntd.0009310.ref003","unstructured":"WHO. 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