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.

Symptoms of kuru include:

• Arm and leg pain
• Coordination problems that become severe
• Difficulty walking
• Headache
• Swallowing difficulty
• Tremors and muscle jerks

Difficulty swallowing and being unable to feed oneself can lead to malnutrition or starvation.

The average incubation period is 10 to 13 years, but an incubation period of 50 years or longer has also been reported.

A neurologic exam may show changes in coordination and walking ability.

There is no known treatment for kuru.

Death usually occurs within 1 year after the first sign of symptoms.

See your health care provider if you have any walking, swallowing, or coordination problems. Kuru is extremely rare. Your provider will check for other nervous system diseases.

Prion disease - kuru

Bosque PJ, Tyler KL. Prions and prion disease of the central nervous system (transmissible neurodegenerative diseases). In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 179.

Tee BL, Geschwind MD. Prion diseases. In: Jankovic J, Mazziotta JC, Pomeroy SL, Newman NJ, eds. Bradley and Daroff's Neurology in Clinical Practice. 8th ed. Philadelphia, PA: Elsevier; 2022:chap 94.

Updated by: Jatin M. Vyas, MD, PhD, Professor in Medicine, Harvard Medical School; Associate in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital, Boston, MA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.