Bovine spongiform encephalopathy (BSE): a stimulus to wider research.

The severity of the epidemic of bovine spongiform encephalopathy which is currently afflicting cattle in the British Isles has stimulated a considerable research effort, much of which is directed toward understanding the aetiology and pathogenesis of the bovine disease. However, a significant thrust has also been orchestrated to address more fundamental issues such as the nature of the uncharacterized causal agents of the wider range of unusual animal and human diseases which share similar characteristics. The background to some of these research programmes is discussed, together with current aims and progress.