Prevalence of porcine toxoplasmosis using ERP-iELISA in Hubei Province.

Toxoplasma gondii (T. gondii) is an intracellular parasite that can infect almost all mammalian species, including humans and important economic animals such as pigs and sheep, thereby causing serious public health security issues. In pigs, such infections are common and economically significant, yet distinguishing between infection routes remains challenging. The current commonly used detection methods mainly aim to quickly detect positive cases of toxoplasmosis but cannot distinguish between different modes of infection. To distinguish whether cysts or oocysts are the source of T. gondii infection, the ERP protein that specifically expressed in T. gondii sporulated oocysts stagewas applied to develop an indirect enzyme-linked immunosorbent assay (iELISA) for specific detection of oocyst-derived porcine toxoplasmosis. This study used the TgGRA1-iELISA and TgERP-iELISA detection methods to conduct a serological survey of toxoplasmosis in pigs in 17 municipalities of Hubei Province, with a total of 2,303 sera samples from 115 farms. Serological detection results demonstrated that TgGRA1-iELISA detected 744 positive samples, with a detection rate of 32.31%, and TgERP-iELISA detected 383 positive samples, with a detection rate of 16.63%, and all positive samples were positive for GRA1 antibody. This indicates that the modes of Toxoplasmosis infection in pigs in Hubei Province are through both cyst infection and oocyst infection. Furthermore, the detection rate of toxoplasmosis varies significantly across different regions. This study provides the first large-scale evidence of oocyst-derived porcine toxoplasmosis in Hubei Province and establishes a tool to support source-targeted prevention strategies in pig farms.