Toxoplasma gondii

Only felids shed fecal stages (oocysts) contaminating pastures, food, and water. Other warm-blooded vertebrates serve as paratenic hosts and are infected ingesting oocysts or other hosts containing tissue stages (bradyzoites). Pigs, sheep, goats, and chickens reared with access to oocyst contaminated soil produce the meats most likely to transmit the infection. Most human infections are asymptomatic, but a primary infection during pregnancy may lead to fetal disease. Also immunocompromized individuals may develop acute disease. Infections can be reduced by restricting the access of cats to food animals, and keeping oocysts in soil from contaminating water or food items, e.g. vegetables.