Transmissible spongiform encephalopathies

Abstract

Abstract Unique among the neurodegenerative diseases, the spongiform encephalopathies are transmissi- ble, either experimentally or as a result of cannibalistic, iatrogenic, or zoonotic infections in humans. First described in the 1920s by Creutzfeldt and Jakob, whose names memorialize its most common form, human spongiform encephalopathy is now recognized to include four other distinctive syndromes: kuru, Gerstmann-Sträussler-Scheinker disease, fatal familial insomnia, and the recently described ‘new variant’ of Creutzfeldt–Jakob disease (vCJD). Scrapie, an endemic disease of sheep and goats, is reliably recorded to have existed in Europe since the mid-1700s (Brown and Bradley 1998), and has since spread to many other parts of the world; in more recent times, a spongiform encephalopathy (chronic wasting disease) has been recognized to be endemic in some species of deer and elk living in the western United States.