Bovine spongiform encephalopathy (BSE) - Mad cow disease

The background to the epidemic of bovine spongiform encephalopathy (BSE) among cattle in the United Kingdom is described as the possible origin of the disease and its relationship to scrapie in sheep. Although the epidemic in cattle is virtually over there is evidence of the transmission of the infectious agent to humans to produce a new variant of Creutzfeldt-Jakob disease. The current status of our understanding of the molecular biology of the infectious agent is described as is the evidence in support of the protein-only, prion, hypothesis. Study of the glycoforms of the prions supports the view that BSE has been transmitted to humans.