{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T06:47:28Z","timestamp":1782283648481,"version":"3.54.5"},"reference-count":66,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T00:00:00Z","timestamp":1782259200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Public Health"],"abstract":"\n This study develops and analyzes a data-driven compartmental model for the transmission dynamics of syphilis among men who have sex with men (MSM) in the United States, incorporating reinfection, two-stage treatment, treatment failure and behavioral adaptation. The model comprises five epidemiological compartments with parameters that capture temporary immunity, adaptive behavior, and heterogeneous treatment outcomes. Analytical results include the derivation of the basic reproduction number (\n \n \n \n \n \n R<\/mml:mi>\n <\/mml:mrow>\n <\/mml:mrow>\n \n 0<\/mml:mn>\n <\/mml:mrow>\n <\/mml:msub>\n <\/mml:math>\n <\/jats:inline-formula>\n ), stability analysis of equilibria, and conditions for backward bifurcation, revealing potential disease persistence even when\n \n \n \n \n \n R<\/mml:mi>\n <\/mml:mrow>\n <\/mml:mrow>\n \n 0<\/mml:mn>\n <\/mml:mrow>\n <\/mml:msub>\n <<\/mml:mo>\n 1<\/mml:mn>\n .<\/mml:mo>\n <\/mml:math>\n <\/jats:inline-formula>\n Using U.S. surveillance data from 2011 to 2023, joinpoint regression identified three major inflection periods 2017, 2019, and 2021 corresponding to shifts in epidemic trajectories. Model calibration demonstrated strong agreement with reported data, yielding MAPE = 14.41% and RMSE = 9376.66, thereby validating the model's predictive accuracy. Simulation and sensitivity analyses underscore the influence of reinfection, behavioral adaptation, and treatment efficacy on disease persistence. Decision-analytic evaluation indicates that a combined approach of enhanced screening, timely treatment, and doxycycline post-exposure prophylaxis can substantially reduce the syphilis burden. The proposed framework provides a robust, quantitative decision-support tool for optimizing intervention strategies among high-risk MSM populations.\n <\/jats:p>","DOI":"10.3389\/fpubh.2026.1841745","type":"journal-article","created":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T05:56:19Z","timestamp":1782280579000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Evaluating syphilis transmission among MSM population: a mathematical model for reinfection, two-stage treatment, and treatment failure"],"prefix":"10.3389","volume":"14","author":[{"given":"Chidozie W.","family":"Chukwu","sequence":"first","affiliation":[{"name":"Department of Mathematical Sciences, Georgia Southern University","place":["Statesboro, GA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dipo","family":"Aldila","sequence":"additional","affiliation":[{"name":"Department of Mathematics, Faculty of Mathematics and Natural Sciences, Universitas Indonesia","place":["Depok, Indonesia"]},{"name":"Innovative Mathematics and Predictive Analytics for Complex System and Technology Laboratory (IMPACT Lab), Universitas Indonesia","place":["Depok, Indonesia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maruf A.","family":"Lawal","sequence":"additional","affiliation":[{"name":"Department of Mathematics, University of Tennessee","place":["Knoxville, TN, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"George","family":"Obaido","sequence":"additional","affiliation":[{"name":"College of Computing, Data Science and Society, University of California, Berkeley","place":["Berkeley, CA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,6,24]]},"reference":[{"key":"B1","unstructured":"National Overview of STIs in 2023\n \n 2024"},{"key":"B2","unstructured":"Sexually Transmitted Infections Surveillance, 2023\n \n 2024"},{"key":"B3","unstructured":"Global Health Sector Strategy on Sexually Transmitted Infections 2016-2021\n \n 2016"},{"key":"B4","unstructured":"Global Progress Report on HIV, Viral Hepatitis and Sexually Transmitted Infections 2023\n \n 2023"},{"key":"B5","doi-asserted-by":"publisher","first-page":"944213","DOI":"10.3389\/fpubh.2022.944213","article-title":"Massive health education through technological mediation: analyses and impacts on the syphilis epidemic in Brazil","volume":"10","author":"Caitano","year":"2022","journal-title":"Front Public Health"},{"key":"B6","first-page":"31","article-title":"Network-based modeling of infectious disease transmission","volume":"462","author":"Li","year":"2019","journal-title":"J Theoret Biol"},{"key":"B7","doi-asserted-by":"publisher","first-page":"1","DOI":"10.15585\/mmwr.rr7301a1","article-title":"Laboratory recommendations for syphilis testing, United States, 2024","volume":"73","author":"Papp","year":"2024","journal-title":"MMWR Recommend Rep"},{"key":"B8","unstructured":"Syphilis: Fact Sheet and Treatment\n \n 2025"},{"key":"B9","doi-asserted-by":"publisher","first-page":"e1","DOI":"10.1093\/cid\/ciab287","article-title":"Previous syphilis alters the course of subsequent episodes of syphilis","volume":"74","author":"Marra","year":"2022","journal-title":"Clin Infect Dis"},{"key":"B10","unstructured":"Primary and Secondary Syphilis\u2014STI Treatment Guidelines. 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