The seroprevalence and distribution of Toxoplasma gondii in pigs in China from 2000 to 2023: a systematic review and meta-analysis

Toxoplasma gondii (T. gondii) is a globally distributed parasite that can infect a diversity of warm-blooded animals, including swine and humans. Infection in swine poses a considerable threat to food safety and public health. The aim of this meta-analysis was to estimate the seroprevalence of T. gondii infection in the swine population in China from 2000 to 2023 and to examine potential factors associated with infection. A total of 112 studies were included, collectively involving 145,152 swine samples originating from 26 provinces. The pooled seroprevalence was 26.0% (95% CI: 23.3%-28.7%). Stratified analysis based on diagnostic methods revealed that studies using the indirect hemagglutination assay (IHA) reported a seroprevalence of 19.7% (95% CI: 17.2%-22.2%), whereas those utilizing the enzyme-linked immunosorbent assay (ELISA) reported a higher seroprevalence of 35.5% (95% CI: 29.1%-41.8%). Geographical analysis indicated higher seroprevalence in the South Central and Southwest regions, whereas the East and Northwest areas reported the lowest seroprevalence. Chongqing Province reported the highest seroprevalence, reaching 44.9% (95% CI: 43.4%-46.0%), followed by Xinjiang, Hainan, and Guizhou, whereas the lowest was observed in Shandong Province (3.5%, 95% CI: 1.7%-6.1%). These findings provide important epidemiological evidence that can inform strategies for the prevention and control of T. gondii infection in swine populations, with a focus on high-risk populations and geographical areas. This imperative contributes substantially to the improvement of both food safety and public health.