Kuru fieldwork in 1981 … and beyond

In 1981, I was fortunate to be able to conduct epidemiological fieldwork on kuru and the experience forever changed me. At the time, the prevalence and incidence had both declined markedly. Yet, clusters of cases still occurred in various villages and questions arose of whether these were the results of the last feast held in each of these areas. I trekked throughout the kuru region, examining current cases and collecting genealogies on 65 recent patients. As described more fully in a paper in Neuroepidemiology (Klitzman et al. 1984) and in a book about my fieldwork in Papua New Guinea, The trembling mountain: a personal account of kuru, cannibals, and mad cow disease (Klitzman 1998), I identified and described three clusters of patients, with patients in each developing kuru virtually simultaneously after having been infected at the same one or two feasts that occurred close together in time. The three pairs had incubation periods of 21, 24 and 28 years, and members of each pair did not vary by more than a year. This research suggested that the disease could therefore follow a uniform course of incubation in two or more people, even when the incubation period is over two decades. It was thus possible to determine when exposure occurred, and hence calculate precisely natural incubation periods for prions in humans—which had not been done before. Yet I found, too, that some participants at each of these feasts had much shorter incubation periods. Hence, age and viral strains did not determine incubation period. Perhaps the initial dose of the agent or the genetics of the infected individual did. We then drew blood from the elderly survivors of multiple feasts, who, in some cases, had had their daughters and other family members succumb to the disease. I also found that at each of these feasts almost 50 people were present. Thus, people had attended many feasts, and in their lifetimes had many opportunities to become infected. I learned, too, about not only the epidemiology but also the anthropology of kuru—about beliefs that sorcery caused and could cure the illness. A countersorcerer, for instance, told me he had cured dozens of cases. His treatment consisted of first uttering an incantation, and then dispensing herbal medicines, and prescribing several behavioural changes: for one week, patients were not allowed to drink water, eat salt or touch members of the opposite sex.