Introduction ToXoplasma gondii has very low host specificity, and it will probably infect almost any mammal. It invades all kinds of cells except RBC Cats (both domestic and wild) are the only definitive hosts and can also be the intermediate hosts The disease that ToXoplasma gondii caused (toxoplasmosis) has been found in virtually every country of the world Toxoplasmosis is a significant cause of morbidity and mortality in AIDS patients and congenitally infected infants--opportunistic infection for human• Toxoplasma gondii has very low host specificity, and it will probably infect almost any mammal. It invades all kinds of cells except RBC • Cats (both domestic and wild) are the only definitive hosts and can also be the intermediate hosts • The disease that Toxoplasma gondii caused (toxoplasmosis) has been found in virtually every country of the world • Toxoplasmosis is a significant cause of morbidity and mortality in AIDS patients and congenitally infected infants -- opportunistic infection for human Introduction