A Papovavirus infection of oligodendroglial cells. Because these cells produce myelin, this disease presents with demyelination. There are multiple poorly demarcated areas of demyelination present within the cerebral, cerebellar, and spinal white matter. The spongiform vacuoles are in the processes of neurons and glia. There are no inflammatory cells.
Most cases are sporadic.
Kuru is limited to the Fore tribe of New Guinea, where it is transmitted by cannibalism. It progresses to complete motor incompacity. Scrapie is a slow virus disease of goats and sheep. Fatal familial insomnia.