Toxoplasma gondii, an intracellular protozoan parasite that enters its host via the gastrointestinal tract. T8075-01G detects the virulent RH strain and is specific for the tachyzoites infectious stage in the T. gondii life cycle. It is the only member of the Toxoplasma genus. The definitive host of T. gondii is cats but it can also be carried by a vast number of warm-blooded animals, including humans. Toxoplasmosis is usually minor and self-limiting but can have serious or even fatal effects on a fetus, or if the host is immunocompromised. T. gondii encephalitis (TE) is the most common cerebral opportunistic infection in patients with AIDS.