Objective  To analyze and assess the relationship between Toxoplasma gondii infection and the risk for schizophrenia.

  Methods  PubMed, EMBASE, Web of Science, Google Scholar, Cochrane Library, China National Knowledge Infrastructure, Wanfang Data Knowledge Service Platform, VIP Databases for Chinese Technical Periodicals were used for the retrieval of literatures of cohort studies of the relationship between Toxoplasma gondii infection and the risk for schizophrenia and related studies published from January 1953 to April 2022. After two researchers independently screened the literature, extracted the data and evaluated the quality of the literatures included in the study, software R 4.1.1 was used for a Meta-analysis.

  Results  Nine studies were included (3 cohort studies and 6 nested case-control studies) with a sample size of 55 352 people. The results of meta-analysis showed that Toxoplasma gondii infection increased the risk for schizophrenia by 47.1% odds ratio (OR)=1.471, 95% confidence interval (CI): 1.137–1.904, P=0.003). The results of heterogeneity test and subgroup analysis showed that the heterogeneity of the study mainly came from publication time, research methods, Toxoplasma gondii antibody detection methods and diagnostic basis for schizophrenia.

  Conclusion  This study confirmed that Toxoplasma gondii infection can increase the risk for schizophrenia, the study result is important for the effective prevention and control of schizophrenia in people infected with Toxoplasma gondii in the future.