{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T19:03:09Z","timestamp":1792609389182,"version":"4.5.0"},"reference-count":29,"publisher":"Oxford University Press (OUP)","issue":"2","license":[{"start":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T00:00:00Z","timestamp":1774483200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"funder":[{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["NIAID R21 AI157618-01A1"],"award-info":[{"award-number":["NIAID R21 AI157618-01A1"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,9,2]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>An initial evaluation found that doxycycline postexposure prophylaxis (doxy-PEP) has a population-level effect on syphilis among cisgender men and transgender women who have sex with men. Whether doxy-PEP's impact is generalizable across the United States and will affect syphilis incidence among cisgender women and pregnant people\u2014populations who seldom receive doxy-PEP\u2014and congenital syphilis (CS) is unknown.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We used public health surveillance data from January 2017 to June 2025 to conduct an interrupted time series analysis of monthly syphilis diagnoses (all stages) overall and by gender before and after doxy-PEP implementation in March 2023 in King County, WA. We estimated the observed and counterfactual number of syphilis cases postimplementation to calculate absolute and relative differences in cases.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>In the postimplementation period, the absolute difference in total syphilis cases was \u22123031 (95% CI: \u22124295, \u22121768) with a relative difference of \u221252.3% (95% confidence interval [CI]: \u221274.1%, \u221230.5%). Among cisgender men, the absolute difference in cases was \u22122248 (95% CI: \u22123321, \u22121175) for a relative difference of \u221253.1% (95% CI: \u221278.5%, \u221227.8%) in the postimplementation period. Cisgender women experienced an absolute difference of \u2212755 cases (95% CI: \u2212939, \u2212572) and a relative difference of \u221246.9% (95% CI: \u221258.3%, \u221235.5%) after doxy-PEP implementation. Among transgender and nonbinary people, the absolute difference in syphilis cases was \u221256 (95% CI: \u221290, \u221223), a relative difference of \u221233.1% (95% CI: \u221253.3%, \u221213.6%), in the postimplementation period. Syphilis cases among pregnant persons rose from 13 in 2017 to 48 in 2024, while CS cases increased from 0 in 2017 to 23 in 2024.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>After the implementation of doxy-PEP, syphilis diagnoses declined dramatically, including among cisgender women. This decline has not affected syphilis in pregnant persons or CS.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/cid\/ciag209","type":"journal-article","created":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T12:42:38Z","timestamp":1774356158000},"page":"267-273","source":"Crossref","is-referenced-by-count":7,"title":["The Population-Level Impact of Doxycycline Postexposure Prophylaxis on Syphilis in King County, WA: An Interrupted Time Series Analysis"],"prefix":"10.1093","volume":"83","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4154-7718","authenticated-orcid":false,"given":"Timothy W","family":"Menza","sequence":"first","affiliation":[{"name":"Division of Allergy and Infectious Disease, University of Washington School of Medicine , Seattle, Washington ,","place":["USA"]},{"name":"HIV\/STI\/HCV Prevention Division, Public Health\u2014Seattle & King County , Seattle, Washington ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna","family":"Berzkalns","sequence":"additional","affiliation":[{"name":"HIV\/STI\/HCV Prevention Division, Public Health\u2014Seattle & King County , Seattle, Washington ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chase A","family":"Cannon","sequence":"additional","affiliation":[{"name":"Division of Allergy and Infectious Disease, University of Washington School of Medicine , Seattle, Washington ,","place":["USA"]},{"name":"HIV\/STI\/HCV Prevention Division, Public Health\u2014Seattle & King County , Seattle, Washington ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9950-2523","authenticated-orcid":false,"given":"Jennifer","family":"Balkus","sequence":"additional","affiliation":[{"name":"HIV\/STI\/HCV Prevention Division, Public Health\u2014Seattle & King County , Seattle, Washington ,","place":["USA"]},{"name":"Department of Epidemiology, University of Washington School of Public Health , Seattle, Washington ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Roxanne P","family":"Kerani","sequence":"additional","affiliation":[{"name":"Division of Allergy and Infectious Disease, University of Washington School of Medicine , Seattle, Washington ,","place":["USA"]},{"name":"HIV\/STI\/HCV Prevention Division, Public Health\u2014Seattle & King County , Seattle, Washington ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1907-9428","authenticated-orcid":false,"given":"Julia C","family":"Dombrowski","sequence":"additional","affiliation":[{"name":"Division of Allergy and Infectious Disease, University of Washington School of Medicine , Seattle, Washington ,","place":["USA"]},{"name":"HIV\/STI\/HCV Prevention Division, Public Health\u2014Seattle & King County , Seattle, Washington ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7449-3774","authenticated-orcid":false,"given":"Matthew R","family":"Golden","sequence":"additional","affiliation":[{"name":"Division of Allergy and Infectious Disease, University of Washington School of Medicine , Seattle, Washington ,","place":["USA"]},{"name":"HIV\/STI\/HCV Prevention Division, Public Health\u2014Seattle & King County , Seattle, Washington ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2026,3,26]]},"reference":[{"key":"2026090211580088800_ciag209-B1","volume-title":"2023 STI surveillance report","author":"Centers for Disease Control and Prevention","year":"2024"},{"key":"2026090211580088800_ciag209-B2","doi-asserted-by":"crossref","first-page":"1296","DOI":"10.1056\/NEJMoa2211934","article-title":"Postexposure doxycycline to prevent bacterial sexually transmitted infections","volume":"388","author":"Luetkemeyer","year":"2023","journal-title":"N Engl J Med"},{"key":"2026090211580088800_ciag209-B3","doi-asserted-by":"crossref","first-page":"1093","DOI":"10.1016\/S1473-3099(24)00236-6","article-title":"Doxycycline prophylaxis and meningococcal group B vaccine to prevent bacterial sexually transmitted infections in France (ANRS 174 DOXYVAC): a multicentre, open-label, randomised trial with a 2\u2008\u00d7\u20082 factorial design","volume":"24","author":"Molina","year":"2024","journal-title":"Lancet Infect Dis"},{"key":"2026090211580088800_ciag209-B4","doi-asserted-by":"crossref","first-page":"308","DOI":"10.1016\/S1473-3099(17)30725-9","article-title":"Post-exposure prophylaxis with doxycycline to prevent sexually transmitted infections in men who have sex with men: an open-label randomised substudy of the ANRS IPERGAY trial","volume":"18","author":"Molina","year":"2018","journal-title":"Lancet Infect Dis"},{"key":"2026090211580088800_ciag209-B5","doi-asserted-by":"crossref","first-page":"273","DOI":"10.1001\/jamainternmed.2024.7186","article-title":"Doxycycline postexposure prophylaxis and bacterial sexually transmitted infections among individuals using HIV preexposure prophylaxis","volume":"185","author":"Traeger","year":"2025","journal-title":"JAMA Intern Med"},{"key":"2026090211580088800_ciag209-B6","doi-asserted-by":"crossref","first-page":"873","DOI":"10.1016\/S1473-3099(25)00085-4","article-title":"Doxycycline to prevent bacterial sexually transmitted infections in the USA: final results from the DoxyPEP multicentre, open-label, randomised controlled trial and open-label extension","volume":"25","author":"Luetkemeyer","year":"2025","journal-title":"Lancet Infect Dis"},{"key":"2026090211580088800_ciag209-B7","doi-asserted-by":"crossref","first-page":"266","DOI":"10.1001\/jamainternmed.2024.7178","article-title":"Doxycycline postexposure prophylaxis and sexually transmitted infection trends","volume":"185","author":"Sankaran","year":"2025","journal-title":"JAMA Intern Med"},{"key":"2026090211580088800_ciag209-B8","volume-title":"Early uptake of doxycycline postexposure prophylaxis and associated STI positivity in the Seattle-King County Sexual Health Clinic","author":"Cannon","year":"2024"},{"key":"2026090211580088800_ciag209-B9"},{"key":"2026090211580088800_ciag209-B10","author":"Balkus","year":"2025"},{"key":"2026090211580088800_ciag209-B11","doi-asserted-by":"crossref","first-page":"1","DOI":"10.15585\/mmwr.rr7302a1","article-title":"CDC clinical guidelines on the use of doxycycline postexposure prophylaxis for bacterial sexually transmitted infection prevention, United States, 2024","volume":"73","author":"Bachmann","year":"2024","journal-title":"MMWR Recomm Rep"},{"key":"2026090211580088800_ciag209-B12","doi-asserted-by":"crossref","first-page":"e11","DOI":"10.1097\/OLQ.0000000000002215","article-title":"Use of doxycycline for sexually transmitted infection postexposure prophylaxis in people assigned female at birth in the United States","volume":"53","author":"Hazra","year":"2026","journal-title":"Sex Transm Dis"},{"key":"2026090211580088800_ciag209-B13","doi-asserted-by":"crossref","first-page":"ofad481","DOI":"10.1093\/ofid\/ofad481","article-title":"The syphilis epidemic among heterosexuals is accelerating: evidence from King County, Washington","volume":"10","author":"Berzkalns","year":"2023","journal-title":"Open Forum Infect Dis"},{"key":"2026090211580088800_ciag209-B14"},{"key":"2026090211580088800_ciag209-B15","doi-asserted-by":"crossref","first-page":"215","DOI":"10.1016\/0304-4076(90)90080-D","article-title":"Seasonal integration and cointegration","volume":"44","author":"Hylleberg","year":"1990","journal-title":"J Econom"},{"key":"2026090211580088800_ciag209-B16","doi-asserted-by":"crossref","first-page":"599","DOI":"10.1093\/biomet\/71.3.599","article-title":"Testing for unit roots in autoregressive-moving average models of unknown order","volume":"71","author":"Said","year":"1984","journal-title":"Biometrika"},{"key":"2026090211580088800_ciag209-B17","doi-asserted-by":"crossref","first-page":"159","DOI":"10.1016\/0304-4076(92)90104-Y","article-title":"Testing the null hypothesis of stationarity against the alternative of a unit root: how sure are we that economic time series have a unit root?","volume":"54","author":"Kwiatkowski","year":"1992","journal-title":"J Econom"},{"key":"2026090211580088800_ciag209-B18","doi-asserted-by":"crossref","first-page":"297","DOI":"10.1093\/biomet\/65.2.297","article-title":"On a measure of lack of fit in time series models","volume":"65","author":"Ljung","year":"1978","journal-title":"Biometrika"},{"key":"2026090211580088800_ciag209-B19","doi-asserted-by":"crossref","first-page":"950","DOI":"10.1016\/j.jclinepi.2014.12.018","article-title":"Interrupted time series analysis in drug utilization research is increasing: systematic review and recommendations","volume":"68","author":"Jandoc","year":"2015","journal-title":"J Clin Epidemiol"},{"key":"2026090211580088800_ciag209-B20"},{"key":"2026090211580088800_ciag209-B21","article-title":"Variation in syphilis among bisexual men and association with syphilis in women. Boston, Massachusetts: Conference on Retroviruses and Opportunistic Infections (CROI)","author":"Cannon","year":"2020"},{"key":"2026090211580088800_ciag209-B22","doi-asserted-by":"crossref","first-page":"695","DOI":"10.1097\/OLQ.0000000000002051","article-title":"Syphilis positivity among men who have sex with men with direct, indirect, and No linkage to female sex partners: exploring the potential for sex network bridging in Baltimore city, MD","volume":"51","author":"Schumacher","year":"2024","journal-title":"Sex Transm Dis"},{"key":"2026090211580088800_ciag209-B23","doi-asserted-by":"crossref","first-page":"866","DOI":"10.1093\/infdis\/jiad368","article-title":"Genomic epidemiology of Treponema pallidum and circulation of strains with diminished tprK antigen variation capability in Seattle, 2021\u20132022","volume":"229","author":"Lieberman","year":"2023","journal-title":"J Infect Dis"},{"key":"2026090211580088800_ciag209-B24","doi-asserted-by":"crossref","first-page":"e87139","DOI":"10.1371\/journal.pone.0087139","article-title":"HIV infection and sexual risk among men who have sex with men and women (MSMW): a systematic review and meta-analysis","volume":"9","author":"Friedman","year":"2014","journal-title":"PLoS One"},{"key":"2026090211580088800_ciag209-B25","doi-asserted-by":"crossref","first-page":"444","DOI":"10.1097\/QAI.0000000000000809","article-title":"Using molecular HIV surveillance data to understand transmission between subpopulations in the United States","volume":"70","author":"Oster","year":"2015","journal-title":"J Acquir Immune Defic Syndr"},{"key":"2026090211580088800_ciag209-B26","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1097\/OLQ.0000000000002071","article-title":"Multilevel drivers of congenital syphilis, Oregon, 2013 to 2021","volume":"52","author":"Menza","year":"2025","journal-title":"Sex Transm Dis"},{"key":"2026090211580088800_ciag209-B27","doi-asserted-by":"crossref","first-page":"1269","DOI":"10.15585\/mmwr.mm7246e1","article-title":"Vital signs: missed opportunities for preventing congenital syphilis\u2014united States, 2022","volume":"72","author":"McDonald","year":"2023","journal-title":"MMWR Morb Mortal Wkly Rep"},{"key":"2026090211580088800_ciag209-B28","doi-asserted-by":"crossref","first-page":"S44","DOI":"10.1097\/OLQ.0000000000001463","article-title":"Decreases in reported sexually transmitted infections during the time of COVID-19 in King County, WA: decreased transmission or screening?","volume":"48","author":"Berzkalns","year":"2021","journal-title":"Sex Transm Dis"},{"key":"2026090211580088800_ciag209-B29","doi-asserted-by":"crossref","first-page":"e59","DOI":"10.1097\/OLQ.0000000000001385","article-title":"The impact of the SARS-CoV-2 pandemic on human immunodeficiency virus and bacterial sexually transmitted infection testing and diagnosis in Oregon","volume":"48","author":"Menza","year":"2021","journal-title":"Sex Transm Dis"}],"container-title":["Clinical Infectious Diseases"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/academic.oup.com\/cid\/advance-article-pdf\/doi\/10.1093\/cid\/ciag209\/67551525\/ciag209.pdf","content-type":"application\/pdf","content-version":"am","intended-application":"syndication"},{"URL":"https:\/\/academic.oup.com\/cid\/article-pdf\/83\/2\/267\/67551525\/ciag209.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/academic.oup.com\/cid\/article-pdf\/83\/2\/267\/67551525\/ciag209.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T15:58:11Z","timestamp":1788364691000},"score":1,"resource":{"primary":{"URL":"https:\/\/academic.oup.com\/cid\/article\/83\/2\/267\/8541760"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,3,26]]},"references-count":29,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2026,3,26]]},"published-print":{"date-parts":[[2026,9,2]]}},"URL":"https:\/\/doi.org\/10.1093\/cid\/ciag209","relation":{},"ISSN":["1058-4838","1537-6591"],"issn-type":[{"value":"1058-4838","type":"print"},{"value":"1537-6591","type":"electronic"}],"subject":[],"published-other":{"date-parts":[[2026,8,15]]},"published":{"date-parts":[[2026,3,26]]}}}