{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T00:58:53Z","timestamp":1791939533363,"version":"4.3.4"},"reference-count":35,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,3,30]],"date-time":"2026-03-30T00:00:00Z","timestamp":1774828800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Toxoplasma gondii establishes latent infection in a substantial proportion of the global population, yet the long-term health consequences of this infection remain incompletely characterized. We conducted a retrospective observational matched cohort study using longitudinal electronic health record data from a nationwide integrated healthcare provider, including members aged 18\u201345 years who underwent routine Toxoplasma serologic screening, typically performed in obstetric evaluation, excluding patients with clinical toxoplasmosis, immunosuppression, or HIV. Seropositive individuals were matched 1:1 without replacement to seronegative controls to align demographic, temporal, and socioeconomic variables. Time-to-event associations with predefined medical conditions were evaluated using Cox proportional hazards models with false discovery rate correction. The final cohort included 19,443 seropositive individuals and 19,443 matched controls (96.7% female), with a tight baseline balance of demographic and temporal characteristics. During follow-up, seropositivity was associated with increased risks of tobacco dependence (aHR 1.65), alcohol dependence (2.32), suicide attempt (1.82), motor vehicle accidents (1.22), and work accidents (1.27), as well as multiple infectious conditions, including hepatitis B (1.55), hepatitis C (2.15), and syphilis (2.43), with an overall trend toward increased all-cause mortality (1.32, 95% CI [1.00\u20131.74]). These findings suggest that asymptomatic Toxoplasma infection in young adults is associated with increased long-term behavioral and medical comorbidity.<\/jats:p>","DOI":"10.3390\/microorganisms14040780","type":"journal-article","created":{"date-parts":[[2026,3,30]],"date-time":"2026-03-30T13:41:53Z","timestamp":1774878113000},"page":"780","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Health Outcomes Associated with Asymptomatic Toxoplasma gondii Seropositivity in Young Adults: A Nationwide Matched Cohort Study"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5646-0071","authenticated-orcid":false,"given":"Sarah","family":"Israel","sequence":"first","affiliation":[{"name":"Department of Clinical Microbiology and Infectious Diseases, Hadassah-Hebrew University Medical Center, Faculty of Medicine, Hebrew University of Jerusalem, P.O. Box 12000, Jerusalem 9112001, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5469-0236","authenticated-orcid":false,"given":"Eugene","family":"Merzon","sequence":"additional","affiliation":[{"name":"Leumit Research Institute, Leumit Health Services, 23 Sprinzak St., Tel Aviv 6473817, Israel"},{"name":"Adelson School of Medicine, Ariel University, Ariel 4070000, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yotam","family":"Shenhar","sequence":"additional","affiliation":[{"name":"Leumit Research Institute, Leumit Health Services, 23 Sprinzak St., Tel Aviv 6473817, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shai","family":"Ashkenazi","sequence":"additional","affiliation":[{"name":"Adelson School of Medicine, Ariel University, Ariel 4070000, Israel"},{"name":"Department of Infectious Diseases, Schneider Children\u2019s Medical Center, 14 Kaplan St., Petah Tikva 4920235, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9765-8938","authenticated-orcid":false,"given":"Abraham","family":"Weizman","sequence":"additional","affiliation":[{"name":"Research Unit, Geha Mental Health Center, Tel Aviv 6997801, Israel"},{"name":"Felsenstein Medical Research Center, Tel Aviv 6997801, Israel"},{"name":"Sagol School of Neurosciences, Faculty of Medical & Health Sciences, Tel Aviv University, Tel Aviv 6997801, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shlomo","family":"Vinker","sequence":"additional","affiliation":[{"name":"Leumit Research Institute, Leumit Health Services, 23 Sprinzak St., Tel Aviv 6473817, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7713-423X","authenticated-orcid":false,"given":"Eli","family":"Magen","sequence":"additional","affiliation":[{"name":"Medicine A Department, Assuta Ashdod University Medical Center, Derech HaRofe 7, Ashdod 7747629, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4389-8896","authenticated-orcid":false,"given":"Ariel","family":"Israel","sequence":"additional","affiliation":[{"name":"Leumit Research Institute, Leumit Health Services, 23 Sprinzak St., Tel Aviv 6473817, Israel"},{"name":"Department of Epidemiology and Preventive Medicine, School of Public Health, Gray Faculty of Medical & Health Sciences, Tel Aviv University, Ramat Aviv, Tel Aviv 6997801, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"673","DOI":"10.1016\/j.cmi.2020.01.008","article-title":"Global Prevalence of Latent Toxoplasmosis in Pregnant Women: A Systematic Review and Meta-Analysis","volume":"26","author":"Rostami","year":"2020","journal-title":"Clin. 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