Kuru (disease)

Kuru was a rare, incurable, and fatal neurodegenerative disorder that was formerly common among the Fore people of Papua New Guinea. It was a prion disease that caused tremors and loss of coordination from neurodegeneration. The term kúru means 'trembling' and comes from the Fore word kuria or guria ("to shake"). It is also known as "laughing sickness" due to abnormal bursts of laughter from the patients. It was spread among the Fore people via funerary cannibalism: deceased family members were traditionally cooked and eaten, which was thought to help free the spirit of the dead. Women and children usually ate the brain, where infectious prions were most concentrated, and therefore were more commonly affected. The outbreak likely originated from a villager developing sporadic Creutzfeldt–Jakob disease, which then spread to others via the consumption of the deceased's brain. Due to a ban by the Australian administration of Papua New Guinea, the Fore had largely stopped eating human flesh around 1960, years before any connection between cannibalism and kuru was seriously considered. However, this did not quickly stop the emergence of new cases, due to the long incubation period of the disease, which can extend to over 50 years. Around 1957, during the peak of the outbreak, about 200 people died of the disease every year. More than half a century later, the outbreak ended, with the two last known deaths occurring in 2005 and 2009.