{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T18:02:58Z","timestamp":1785780178283,"version":"3.56.0"},"update-to":[{"DOI":"10.1371\/journal.pntd.0013998","type":"new_version","label":"New version","source":"publisher","updated":{"date-parts":[[2026,3,2]],"date-time":"2026-03-02T00:00:00Z","timestamp":1772409600000}}],"reference-count":41,"publisher":"Public Library of Science (PLoS)","issue":"2","license":[{"start":{"date-parts":[[2026,2,23]],"date-time":"2026-02-23T00:00:00Z","timestamp":1771804800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/publicdomain\/zero\/1.0\/"}],"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>\n                      Trachoma, an infectious eye disease caused by\n                      <jats:italic>Chlamydia trachomatis<\/jats:italic>\n                      (\n                      <jats:italic>Ct<\/jats:italic>\n                      ), remains endemic in Ethiopia\u2019s Amhara region despite implementation of the Surgery, Antibiotic, Facial Cleanliness, and Environmental Improvement (SAFE) strategy since 2007. Once a formerly endemic district has reached the trachoma elimination threshold of a trachomatous inflammation-follicular (TF) prevalence of &lt;5% among children ages 1\u20139 years and mass drug administration has been halted, there is concern that the prevalence could recrudesce back above 5% over time. Formerly endemic districts that are adjacent to still-endemic districts may be at greater risk of recrudescence. This study aimed to evaluate the inclusion of\n                      <jats:italic>Ct<\/jats:italic>\n                      infection and antibody testing to complement traditional clinical measures (TF) in Albuko, Bibugn, Debre Birhan Town, and Fagita Lekoma, four low-endemic districts at risk for recrudescence.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Methodology<\/jats:title>\n                    <jats:p>\n                      These four district-level surveys were conducted between March and May 2022. Children ages 1\u20139 years (n\u2009=\u20092,424) were assessed for TF by certified graders and provided dried blood spots (DBS) for serological analysis. Children ages 1\u20135 years (n\u2009=\u20091,588) also provided conjunctival swabs to test for\n                      <jats:italic>Ct<\/jats:italic>\n                      infection.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      The TF prevalence in this age group was\u2009&lt;\u20095% in all four districts. The antibody seroconversion rate (SCR) ranged from 0.1 per 100 children per year in Fagita Lekoma to 1.1 per 100 children per year in Debre Birhan Town, suggesting low transmission compared to proposed low-endemicity thresholds (SCR\u2009\u2264\u20091.6). Further, no positive\n                      <jats:italic>Ct<\/jats:italic>\n                      infection cases were detected across the four districts.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec004\">\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>The data confirmed that despite being adjacent to trachoma-endemic districts, the four surveyed districts have maintained or achieved the elimination threshold. Additionally, the use of complementary indicators supported clinical evidence of very low disease transmission in these districts. This study highlights that including complementary indicators into surveys provides additional certainty for low-endemicity settings within a region still working towards trachoma elimination.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pntd.0013998","type":"journal-article","created":{"date-parts":[[2026,2,23]],"date-time":"2026-02-23T18:46:57Z","timestamp":1771872417000},"page":"e0013998","update-policy":"https:\/\/doi.org\/10.1371\/journal.pntd.corrections_policy","source":"Crossref","is-referenced-by-count":3,"title":["Monitoring of Chlamydia trachomatis infection and antibodies in low-prevalence districts of Amhara, Ethiopia: Insights from a hyper-endemic trachoma region"],"prefix":"10.1371","volume":"20","author":[{"given":"Anna J.","family":"Harte","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ambahun","family":"Chernet","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Getahun","family":"Ayenew","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tania A.","family":"Gonzalez","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karana","family":"Wickens","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarah","family":"Gwyn","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eshetu","family":"Sata","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ayalew","family":"Shiferaw","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Demelash","family":"Gessese","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zebene","family":"Ayele","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kimberly A.","family":"Jensen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adisu","family":"Abebe","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zerihun","family":"Tadesse","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"E. 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