WHAT ARE ANIMALS AND RABIES NEGRI BODIES, BRAIN TISSUE TEST?
A postmortem histologic examination of the brain tissue of an animal suspected to have rabies, usually performed after the animal has bitten a human. Rabies produces Negri bodies, a specific and diagnostic lesion of the central nervous system that contains inclusion bodies in the cytoplasm of the nerve cells. Animal specimen examination is the only method to identify rabies because there is no laboratory or diagnostic test to identify the disease in humans until after symptoms appear (listed below). Diagnosis in humans is based on history and symptoms. Symptoms may appear 10 days to a year after the bite but more commonly appear in humans 2-8 weeks later.