{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"institution":[{"name":"medRxiv"}],"indexed":{"date-parts":[[2026,1,16]],"date-time":"2026-01-16T11:54:03Z","timestamp":1768564443558,"version":"3.49.0"},"posted":{"date-parts":[[2023,2,16]]},"group-title":"Epidemiology","reference-count":58,"publisher":"openRxiv","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"accepted":{"date-parts":[[2023,5,17]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                <jats:p>\n                  Trachoma, caused by ocular\n                  <jats:italic>Chlamydia trachomatis<\/jats:italic>\n                  infection, is targeted for global elimination as a public health problem by 2030. To provide evidence for use of antibodies to monitor\n                  <jats:italic>C. trachomatis<\/jats:italic>\n                  transmission, we collated IgG responses to Pgp3 antigen, PCR positivity, and clinical observations from 19,811 children aged 1\u2013 9 years in 14 populations. We demonstrate that age-seroprevalence curves consistently shift along a gradient of transmission intensity: rising steeply in populations with high levels of infection and active trachoma and becoming flat in populations near elimination. Seroprevalence (range: 0\u201354%) and seroconversion rates (range: 0\u201315 per 100 person-years) correlate with PCR prevalence (r: 0.87, 95% CI: 0.57, 0.97). A seroprevalence threshold of 13.5% (seroconversion rate 2.75 per 100 person-years) identifies clusters with any PCR-identified infection at high sensitivity (&gt;90%) and moderate specificity (69-75%). Antibody responses in young children provide a robust, generalizable approach to monitor population progress toward and beyond trachoma elimination.\n                <\/jats:p>","DOI":"10.1101\/2023.02.13.23285881","type":"posted-content","created":{"date-parts":[[2023,2,16]],"date-time":"2023-02-16T15:35:12Z","timestamp":1676561712000},"source":"Crossref","is-referenced-by-count":0,"title":["Monitoring transmission intensity of trachoma with serology"],"prefix":"10.64898","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3403-5765","authenticated-orcid":false,"given":"Christine","family":"Tedijanto","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7101-6649","authenticated-orcid":false,"given":"Anthony W.","family":"Solomon","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Diana L.","family":"Martin","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5741-8537","authenticated-orcid":false,"given":"Scott D.","family":"Nash","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7118-1457","authenticated-orcid":false,"given":"Jeremy D.","family":"Keenan","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8216-0240","authenticated-orcid":false,"given":"Thomas M.","family":"Lietman","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2139-6564","authenticated-orcid":false,"given":"Patrick J.","family":"Lammie","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1886-2699","authenticated-orcid":false,"given":"Kristen","family":"Aiemjoy","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Abdou","family":"Amza","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4967-9627","authenticated-orcid":false,"given":"Solomon","family":"Aragie","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7022-282X","authenticated-orcid":false,"given":"Ahmed M.","family":"Arzika","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"E. 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