The association between Toxoplasma gondii and schizophrenia: an analysis of the seroepidemiological evidence
DOI:
https://doi.org/10.18004/mem.iics/1812-9528/2025.e23162501Keywords:
Toxoplasma gondii, schizophrenia, seroprevalence, chronic infectionAbstract
Schizophrenia is a complex neuropsychiatric disorder with a multifactorial etiology involving both genetic and environmental factors. Among the latter, Toxoplasma gondii infection has been proposed as a potential risk factor, given its ability to establish latent infections in the central nervous system and modulate neuroimmune functions. This review analyzes the existing evidence on the association between T. gondii and schizophrenia. Numerous studies report higher seroprevalence of anti-T. gondii IgG antibodies in patients with schizophrenia compared to healthy controls, with marked regional variability. Additionally, some studies show higher antibody titers among patients, suggesting a more active or sustained immune response. However, findings are inconsistent, and several studies fail to detect significant associations. This heterogeneity may be due to methodological differences, sociodemographic factors, genetic variability, and comorbid infections. Overall, current evidence partially supports the hypothesis that T. gondii acts as a cofactor within a broader multifactorial model of schizophrenia. Further longitudinal and well-controlled studies are needed to clarify the temporal relationship and underlying mechanisms.
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