Transmission of human spongiform encephalopathies to experimental animals: comparison of the chimpanzee and squirrel monkey.

The agents of kuru and Creutzfeldt-Jakob disease have been consistently transmitted from patients with those diseases to chimpanzees and squirrel monkeys, as well as to other new-world primates, with average incubation periods of two or three years. No other animals have been found so consistently susceptible to the agents in human tissues. More rapid and convenient assays for the infectious agents would greatly facilitate research on the spongiform encephalopathies of humans.