Toxoplasma gondii infection in pig intended for human consumption in Brazil: seroprevalence, risk factors and influence of Biosecurity Measures

Abstract

Background: Toxoplasmosis, caused by Toxoplasma gondii, is a zoonotic disease highly prevalent in Brazil and poses considerable risk to public health. T. gondii is an obligate intracellular protozoan that is capable of infecting mammals and birds. In humans, the infection occurs mainly by the ingestion of raw or undercooked meat containing tissue cysts or other food items or water contaminated with sporulated oocysts, or by congenital transmission. Despite the prevalence of T. gondii in Brazil and its proven circulation among humans, animals, and the environment, there have been few studies on toxoplasmosis and its epidemiology. Methods: Blood samples were collected from 416 pigs from 55 producer farms in 27 municipalities in the state of Espírito Santo, Brazil. An indirect immunofluorescent assay (IFA) was performed to estimate the seroprevalence of T. gondii and identify the associated risk factors. Results: The T. gondii antibody prevalence rate in commercial swine herds from Espírito Santo was 15.4% (64/416), and the most frequent antibody titer was 1:64 (61/64) followed by 1:256 (3/64). Seropositivity for T. gondii was related to the presence of cats, existence of internal insulation fences on the farm, use of compost chambers on the farm, water sources, and the age of pigs. Conclusions: To the best of our knowledge, this is the first study to report anti- T. gondii antibodies in the serum of pigs in the state of Espirito Santo, Brazil. This finding is important to public health because seropositive pigs can harbor tissue cysts in their meat, thereby representing a zoonotic risk for consumers of raw or undercooked porcine meat or its products.