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noun, plural: toxoplasmoses

An acute or chronic, widespread disease of animals and humans caused by the obligate intracellular protozoon Toxoplasma gondii


Toxoplasmosis is a disease that is caused by the obligate intracellular protozoon Toxoplasma gondii. Toxoplasma gondii is the only species in the genus Toxoplasma. It is an obligate intracellular parasite. Its definitive hosts are felids such as domestic cats. Its intermediate hosts are various warm-blooded animals, such as rodents, and birds. The infective stage is the oocysts containing the pathogen in the faeces of cats, usually by contaminated soil, direct exposure to infected faeces, tissue cysts in infected meat or tachyzoites (proliferating forms) in blood.

This protozoon may also infect humans and cause toxoplasmosis. The symptoms are typically mild, such as muscle aches and tender lymph nodes. However, toxoplasmosis in pregnant women may cause damage to the fetus (congenital toxoplasmosis). Immunocompromised patients with toxoplasmosis may suffer from seizures and poor coordination.

In humans, the parasite is acquired by consuming insufficiently cooked meat containing the parasite or by contact with cat feces contaminated with the parasite.

Word origin: Ancient Greek tóxon (“bow”) + plásm(a) (“something molded, bow-shaped form") + -osis

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  • toxoplasmic (adjective, of, or relating to toxoplasmosis)