The end of the BSE saga: do we still need surveillance for human prion diseases?

The epidemics of classical bovine spongiform encephalopathy (BSE) and variant Creutzfeldt-Jakob disease (vCJD) related to BSE-infected food are coming to an end. The decline in concern about these diseases may invite complacency and questions whether surveillance for human prion diseases is still necessary. This article reviews the main points of surveillance and why it is still needed: animal sources for human prion infection other than BSE cannot be excluded; the potentially increasing circulation of prions between humans by blood, blood products and medical procedures; the prevalence of vCJD prion carriers in the UK; and the scientific study of prion diseases as paradigm for other neurodegenerative diseases with "prion-like" spread of pathological proteins. We conclude that continuation of detailed surveillance of human prion disorders would be prudent in view of all these points that deserve clarification.