Daniel Carleton Gajdusek
Gajdusek thought that kuru was spread by the ritualistic eating of the brains of dead family members. He proved this idea by infecting primates with the disease and showing that it had an very long incubation period of several years. When the cannibalism was stopped, kuru stopped spreading in just one generation. This was the first time it was shown that a non-inflammatory degenerative disease could be spread in humans.