Research overview: toxoplasmosis in immunocompromised felids

While cats typically host Toxoplasma without illness, immunocompromise can unleash severe, even fatal toxoplasmosis in felids. This overview surveys the conditions under which the parasite causes clinical disease in cats, including concurrent infection with immunosuppressive viruses, stress and young age, and the resulting pneumonia, hepatitis and neurological disease. It examines documented cases in captive and wild felids, the diagnostic challenges, and the interplay between Toxoplasma and other pathogens that compromise immunity. The synthesis connects host immune status to disease outcome. It aims to help readers understand that the relationship between cats and Toxoplasma is conditional, and that the same parasite that quietly shedding cats carry harmlessly can become a lethal opportunist when the immune system, weakened by co-infection or stress, can no longer hold it in check.