Asynchronous Onset of Clinical Disease in BSE-Infected Macaques

To estimate the effect of the variability of prion disease onset on primary bovine spongiform encephalopathy transmission to humans, we studied 6 cynomolgus macaques. The preclinical incubation period was significantly prolonged in 2 animals, implying that onset of variant Creutzfeldt-Jacob disease in humans could be more diverse than previously expected.