Toxoplasmosis: Epidemiology with the emphasis of its public health importance

Toxoplasmosis is a protozoal disease, which is capable of infecting any warm-blooded animals, including humans. Wild and domestic cats are the only known definitive hosts of Toxoplasma; they can develop both systemic and patent intestinal infection. All other animals and humans serve as intermediate hosts in which the parasite may cause systemic infection, which typically results in the formation of tissue cysts. In all species, Toxoplasma infection is usually subclinical, although it may occasionally cause mild, non specific signs. Infection may have much more serious consequences in immunocompromised or pregnant animals and people and AIDS patients. The major modes of transmission include consumption of undercooked meat containing Toxoplasma cysts, fecal-oral transfer of Toxoplasma oocysts from cat feces (either directly or in contaminated food, water or soil), and vertical transmission from mother to fetus if primary infection occurs during pregnancy. The major public health significance is the risk of having cats in the same hold with pregnant women, children and immunocompromised patients which are highly susceptible to the disease. When women are exposed during pregnancy, brith defects such as abortion, still birth, blindness and hydro most commonly encountered congenital significance of T.gondii is mainly due to reproductive failure in animals, condemnation of meat and wastage of milk, treatment cost in humans and vaccination cost in cats.