At the beginning of this month, Stanley Prusiner of the University of California, San Francisco, was awarded the Nobel Prize in Physiology or Medicine for his work on the infectious agent that causes spongiform encephalopathies _ the prion. His ‘protein-only’ theory now has many advocates, and the advances that have been made, the questions that remain and the ways in which these could be addressed are discussed in this feature.
- Adriano Aguzzi
- Charles Weissmann
