Age susceptibility could be the key to Britain's BSE outbreak

Abstract

Although bovine spongiform encephalopathy (BSE) is known to spread by contaminated meat and bone meal (MBM), it has confused researchers why BSE emerged only in Britain when cows all over the world have been eating MBM since the 1950s. Recent evidence, however, indicates that MBM was fed to young calves during the 1970s in Britain, but not in the rest of Europe or the United States. Epidemiological data had already suggested young calves might have a higher risk of developing BSE, and this finding parallels the susceptibility young humans have to the human BSE variant, Creutzfeldt-Jakob disease. This new information calls into question the ideas that the British BSE outbreak was caused by a genetic mutation or as a result of cows eating MBM from contaminated sheep. LO