Molecular detection and genetic characterization of Toxoplasma gondii in pork in Shanghai, China

Abstract

Toxoplasma gondii in pork products has become an important public health problem worldwide. However, the prevalence of pork with T. gondii has rarely been reported. In this study, we assessed the prevalence and genotypic characterization of T. gondii in pig meats. Five slaughterhouses and 100 retail stores were surveyed in Shanghai. A total of 750 samples were collected and 63 (8.4%) samples were found to be positive by nested PCR targeting the ITS1 gene. Three of the slaughterhouses and 20 retail stores had positive specimens, and a higher infection rate was seen in the hot season than in the cold season. Similar positive rates were detected in pork from slaughterhouses (8.2%) and from retail stores (8.7%). The prevalence in supermarkets (13.3%) was higher than in farmers markets (4.0%). All positive samples were typed at 11 loci using PCR-RFLP methods. Two samples were completely typed at all loci, and two samples were typed at eight loci, all were identified as ToxoDB#9. To our knowledge, there is no previously published report of T. gondii in pork in Shanghai, and these results will provide data to support food safety and will benefit the control of toxoplasmosis in pigs.