Kuru: The Laughing Death and the Feast That Spread It

Picture a valley in the eastern highlands of Papua New Guinea in the middle of the last century. A woman who was healthy at planting season begins to sway when she walks. By harvest she cannot stand without a staff, her limbs shake, and at intervals she breaks into helpless laughter that has nothing to do with joy. Her family does not think she is ill. They think someone has cursed her.

The disease was called kuru, a word in the Fore language meaning to shake or tremble. Outsiders called it the laughing death, for the pathological bursts of laughter and the fixed grimace that came with its later stages. Between roughly the 1950s and 1960s it killed on a scale that threatened to unmake Fore society, and it fell overwhelmingly on women and young children.

A curse, in the eyes of the Fore

To the Fore, kuru was not natural. It was sorcery, the work of an enemy who had taken a scrap of the victim's food, hair or waste and worked black magic over it, a bundle they buried to make the person sicken and die. The sudden appearance of the trembling was read as an omen that a person had been marked. Communities held sorcery hearings and sometimes killed accused sorcerers, so the sickness bred a second wave of death by suspicion. This was the honest, internal logic of the culture, and it was wrong about the cause while being painfully right that the disease was passed from person to person.

What was really killing them

Kuru is a prion disease. Prions are not bacteria or viruses but ordinary proteins folded into a wrong shape, and the misfolded form induces healthy proteins to misfold in turn, riddling the brain until it fails. There is no fever, no germ to find, only a slow, fatal unraveling of the nervous system. The route of transmission was funerary. In Fore mortuary custom the bodies of the dead were consumed by their relatives as an act of love and mourning, and the women and children who prepared and ate the brain and nervous tissue received the heaviest dose of infectious material. That is why the disease clustered in exactly those people.

The American physician Carleton Gajdusek established that kuru was transmissible, work that earned a share of the 1976 Nobel Prize in Physiology or Medicine and helped open the whole field of prion science. Once the mortuary practice was discouraged and largely stopped through the late 1950s and 1960s, new infections fell away, though the long incubation meant late cases surfaced for decades afterward.

Where the tidy story frays

The science is complete enough to be genuinely humbling: a folded protein, a shared meal, a decades-long fuse. What it does not soften is the human residue in the record, the named villages, the mothers gone within a year of the first stumble, the certainty of families that they were watching a curse work rather than a molecule. The Fore were mistaken about sorcery and correct that the danger passed through the closest bonds they had. Both things were true at once.

Readers have filed their own accounts of sicknesses blamed on curses and afflictions no one could name, and each is voted True, Fake or Not sure. Read them and enter your own judgment.