BSE=CJD?

Although BSE has become very common in British cattle, and although it is known that prion diseases, including human prion diseases, can be transmitted orally, until recently the bulk of opinion has been that human infection is unlikely to occur.

This view was founded entirely on the judgement that human and bovine prion protein were so genetically distinct as to make it unlikely that they could interact with each other.

Until recently there has been no evidence against this view, because there was no definite increase in incidence of human prion diseases in Britain, and no cases were definitely linked to BSE exposure.

All this has changed recently following the identification of 10 cases of CJD in the previous 24 months with the following unusual features:

Age at onset less than 42 years

Presentation with psychiatric symptoms followed by neurological deficits

Prolonged course

Pronounced amyloid deposition

(NB Latest findings reported in Nature, Autumn 1996. These were not included in this presentation, but they provide considerable further support for the theory that BSE is responsible for the new variant CJD cases.)