I am in one of the most remote, recently opened regions of New Guinea, in the center of tribal groups of cannibals, only contacted in the last ten years—still spearing each other as of a few days ago, and cooking and feeding the children the body of a kuru case, the disease I am studying—only a few weeks ago.
But Gajdusek had never seen any actual cannibalism and he had very little real knowledge about kuru. Beyond the stress-related hypothesis, there was some conjecture that the deadly condition might be the result of an environmental toxin. Others believed that kuru was a hereditary disorder. Consequently, Gajdusek got busy. He spent months collecting blood, feces, and urine from the locals. He ran tests on those stricken by the disease and, with the aid of translators, he conducted interviews with victims and their family members.
By mid-1957, Gajdusek was working with Vin Zigas, a medical doctor who had already been gathering information, as well as his own blood samples. That November their initial findings were published in the prestigious New England Journal of Medicine. Kuru, the authors claimed, was a degenerative disease of the central nervous system. They described the clinical course of the disease as well as its curious preference for striking three times as many women as men. The skewed sex ratios were difficult to pick up, however, since more men were being killed for having been kuru sorcerers. For the Fore, ritual murder had become the great equalizer. In what would later become an important observation, Gajdusek also noted that kuru occurred equally in children of both sexes.
The researchers sent off blood and tissue samples for analysis but the results showed no evidence of viral infection, nor did they appear to indicate the presence of a toxin (they had suspected that the Fore were possibly being poisoned by heavy metals in their diet). But a number of the tissue specimens did show something remarkable—although it was as much about what the samples lacked as what they exhibited. After examining the brains of eight kuru victims, scientists at the National Institute of Health (NIH) in Bethesda, Maryland, reportedly found no evidence of inflammation or any immune response. That meant the victim’s body had not been fighting off a pathogenic organism like a virus, bacterium, or fungus. In most cases, at the first signs of a viral, bacterial, or fungal intruder, the body initiates a sustained, multi-pronged defense consisting of non-specific responses like swelling and inflammation, and cell-mediated responses like the production of antibodies—proteinaceous particles that bind to foreign proteins (antigens) found on foreign cells and viruses.47
What the investigators did find was that large regions of the cerebellum (which sits like a small head of cauliflower behind the cerebral hemispheres) were full of holes.
Igor Klatzo, an NIH researcher, had seen a disease like this only once before. “The closest condition I can think of,” he said, “is that described by Jakob and Creutzfeldt.”
Another NIH scientist noticed a similarity between kuru and the transmissible spongiform encephalopathy (TSE) known as scrapie, an unusual infectious agent of sheep. Scrapie, which was present in European sheep by the beginning of the 18th century, was named for one of its symptoms, namely the compulsive scraping of the stricken animal’s fleece against objects like fences or rocks. It had been previously been classified as a “slow virus,” an archaic term for a virus with a long incubation period, in which the first symptoms might not appear for months or even years after exposure. Klatzo and William Hadlow, who had made the kuru/scrapie connection, now suspected that the cause of kuru might also be a slow virus.
At this point, Ronald Berndt tried to reassert himself as the world’s leading authority on the New Guinea highlands and its indigenous inhabitants. Miffed that medical researchers were intruding on what he considered his anthropological turf, he refused to be outdone by upstarts like Gajdusek. Berndt wrote his own article on kuru, reemphasizing the importance of sorcery and resurrecting the original stress-related explanation. Fear alone, Berndt claimed, was probably enough to initiate the irreversible symptoms of kuru.
Fortunately, though, in what many might argue was a strong positive step for kuru research, Berndt and his wife refused to share their “data” and “expertise” with those who were actually doing real research on the disease. Gajdusek, for his part, dismissed Berndt’s baseless assertions, believing instead that the high occurrence of kuru among young children argued against a psychological origin for the disease. He was leaning toward the explanation proposed by genetics professor Henry Bennett, who attempted to explain the discrepancy between male and female adults dying of kuru.