Etiologic agent = Toxoplasma gondii

Toxoplasmosis is one of the best known zoonotic diseases among physicians, veterinarians and the public. The etiologic agent, Toxoplasma gondii, is a coccidian protozoan pathogen of humans and a variety of animal species. In all hosts, the organism enters a chronic, persistent phase following acute infection, and this persistence leads to the potential for reactivation of clinical disease at a later date (a particularly serious problem in AIDS patients).

Cats play a critical role in the life cycle and maintenance of the organism in nature. Cats are, in fact, the only definitive host in which T. gondii can undergo sexual reproduction to produce infectious oocysts/sporozoites. However, humans can be infected with Toxoplasma gondii by 3 different mechanisms, only one of which is direct contact with cat feces. Therefore, the overall role of cats in the epidemiology of human exposure to T. gondii needs to be viewed from a basis in fact, not fear.

Toxoplasmosis topics

(To view any of these topics, simply click on the appropriate subject.)

• Life cycle of Toxoplasma gondii
• Mechanisms of human infection with Toxoplasma gondii
• Congenital toxoplasmosis
• Acute toxoplasmosis in immunocompetent humans
• Toxoplasmosis in immunosuppressed humans
• Toxoplasmosis in domestic animals
• Diagnosis and treatment in cats and dogs
• Ways to reduce human infection
• Vaccination of cats to reduce their role as reservoirs of Toxoplasma gondii
• References

First Toxoplasmosis topic