POURPOSE: This study aimed to investigate the seroepidemiological status of Toxoplasma gondii (T. gondii) infection in Multiple Sclerosis (MS) patients compared to controls. METHODS: The present study included 98 MS patients and 100 controls. Demographic and clinical information collected through interviews, electronic medical records, and clinical examinations. Serum samples analyzed for anti-T. gondii IgG and IgM antibodies using ELISA. RESULTS: A significant difference observed in the seroprevalence of anti-T. gondii IgG between 49 MS patients (50%) and 33 controls (33%). MS patients with seropositive anti-T. gondii IgG had significantly different age, Expanded Disability Status Scale (EDSS) scores, MS phenotypes, age of diagnosis, and age of onset compared to seronegative patients. Serum levels of anti-T. gondii IgG significantly elevated in the case group compared to the control group (277.8 ± 28.61 vs. 137.1 ± 9.52, P <
0.0002). In controls, all subjects were seronegative for anti-T. gondii IgM
three MS cases were positive, showing no significant difference in anti-T. gondii IgM seroprevalence between groups. CONCLUSION: The study suggests a potential association between T. gondii infection and MS, indicating that anti-T. gondii IgG positivity may correlate with MS phenotypes and influence disease progression. This suggests that chronic toxoplasmosis may be risk factor for MS.