{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"institution":[{"name":"medRxiv"}],"indexed":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T10:00:18Z","timestamp":1785146418887,"version":"3.55.0"},"posted":{"date-parts":[[2026,3,5]]},"group-title":"Epidemiology","reference-count":27,"publisher":"openRxiv","license":[{"start":{"date-parts":[[2026,3,5]],"date-time":"2026-03-05T00:00:00Z","timestamp":1772668800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/www.medrxiv.org\/about\/FAQ#license"}],"funder":[{"DOI":"10.13039\/100000060","name":"National Institute of Allergy and Infectious Diseases","doi-asserted-by":"crossref","award":["K23AI182453"],"award-info":[{"award-number":["K23AI182453"]}],"id":[{"id":"10.13039\/100000060","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"accepted":{"date-parts":[[2026,7,23]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                <jats:sec>\n                  <jats:title>Background<\/jats:title>\n                  <jats:p>Congenital syphilis remains a preventable cause of neonatal morbidity and mortality despite the availability of inexpensive diagnostics and effective treatment. We aimed to evaluate the maternal and congenital syphilis burden at the Instituto Nacional Materno Perinatal, Peru\u2019s national referral center for maternal and perinatal care.<\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>Methods<\/jats:title>\n                  <jats:p>We conducted a retrospective analysis of aggregated, de-identified surveillance data from January 2023 to December 2025. We calculated the prevalence of maternal syphilis and incidence of congenital syphilis, and compared those estimates with World Health Organization (WHO) elimination benchmarks.<\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>Among 59,598 pregnant women screened, maternal syphilis prevalence ranged between 1.0% and 1.2%. Across 36,094 live births, congenital syphilis incidence ranged between 383 and 526 per 100,000 live births, consistently exceeding the WHO target of 50 per 100,000 live births. Over half of maternal infections were diagnosed at outside facilities before referral. Reported treatment coverage exceeded 90% among mothers and reached 100% among infants.<\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>Conclusions<\/jats:title>\n                  <jats:p>Congenital syphilis incidence consistently exceeded elimination benchmarks despite relatively stable maternal syphilis prevalence, highlighting potential gaps in timely diagnosis and linkage between diagnosis and treatment.<\/jats:p>\n                <\/jats:sec>","DOI":"10.64898\/2026.03.04.26347675","type":"posted-content","created":{"date-parts":[[2026,3,5]],"date-time":"2026-03-05T22:25:13Z","timestamp":1772749513000},"source":"Crossref","is-referenced-by-count":0,"title":["Maternal and congenital syphilis at a national referral center in Peru, 2023-2025"],"prefix":"10.64898","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-1119-027X","authenticated-orcid":false,"given":"William","family":"Leung","sequence":"first","affiliation":[{"name":"Harvard University, Cambridge, MA, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9209-2480","authenticated-orcid":false,"given":"Carlos","family":"Vel\u00e1squez V\u00e1squez","sequence":"additional","affiliation":[{"name":"Instituto Nacional Materno Perinatal, Lima, Peru"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1817-8187","authenticated-orcid":false,"given":"Luis","family":"Meza Santiva\u00f1ez","sequence":"additional","affiliation":[{"name":"Instituto Nacional Materno Perinatal, Lima, Peru"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3267-1904","authenticated-orcid":false,"given":"Pedro","family":"Arango-Ochante","sequence":"additional","affiliation":[{"name":"Instituto de Investigaciones en Ciencias Biom\u00e9dicas (INICIB), Universidad Ricardo Palma, Lima, Peru"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2836-0174","authenticated-orcid":false,"given":"Kelika A.","family":"Konda","sequence":"additional","affiliation":[{"name":"Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8188-9598","authenticated-orcid":false,"given":"Silver K.","family":"Vargas","sequence":"additional","affiliation":[{"name":"Unit of Health, Sexuality and Human Development, and Laboratory of Sexual Health, Universidad Peruana Cayetano Heredia, Lima, Peru"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8101-0790","authenticated-orcid":false,"given":"Carlos F.","family":"C\u00e1ceres","sequence":"additional","affiliation":[{"name":"Unit of Health, Sexuality and Human Development, and Laboratory of Sexual Health, Universidad Peruana Cayetano Heredia, Lima, Peru"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6922-7364","authenticated-orcid":false,"given":"Jeffrey D.","family":"Klausner","sequence":"additional","affiliation":[{"name":"Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4077-3476","authenticated-orcid":false,"given":"Lao-Tzu","family":"Allan-Blitz","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"54368","reference":[{"key":"2026072702050827000_2026.03.04.26347675v3.1","unstructured":"Global Progress Report on HIV, Viral Hepatitis and Sexually Transmitted Infections, 2021. 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