Kuru is a very rare disease. It is caused by an infectious protein (prion) found in contaminated human brain tissue.

Kuru is found among people from New Guinea who practiced a form of cannibalism in which they ate the brains of dead people as part of a funeral ritual. This practice stopped in 1960, but cases of kuru were reported for many years afterward because the disease has a long incubation period. The incubation period is the time it takes for symptoms to appear after being exposed to the agent that causes disease.

Kuru causes brain and nervous system changes similar to Creutzfeldt-Jakob disease. Similar diseases appear in cows as bovine spongiform encephalopathy (BSE), also called mad cow disease.

The main risk factor for kuru is eating human brain tissue, which can contain the infectious particles.