Research finds potential for epidemic

What is the likelihood of an epidemic of new variant Creutz-feldt- Jakob Disease (nvCJD)?

Experimental evidence of a direct link between nvCJD and bovine spongiform encephalo-pathy (BSE) in cattle reported yesterday, confirms the potential for an epidemic only. We are no nearer knowing whether or not we face one.

When will we know?

In six, 12 or 18 months' time, according to Professor John Pattison, chairman of the Government's Spongiform Encephalopathy Advisory Com- mittee. But it all depends on the average incubation period of nvCJD, and that is unknown.

Reported cases of nvCJD may be those in whom the disease has the shortest incubation period. The average incubation might be 20 years or more. We just have to wait and see and for the "best-case" scenario - the least number of cases - we have to wait longer.

Should people stop eating beef following the new findings?

It is a matter of personal - and informed - choice. The Government and the beef industry insist British beef is safer than it has ever been. More importantly, Professor Pattison, an independent and widely-respected scientist who has regarded openness with the press and public as a priority in this crisis , says he would eat beef today "without reservation".

What are the implications of a test for nvCJD?

The new research paves the way for a test for nvCJD, using the distinctive "molecular marker" in the prion protein characteristic of spongiform dis- eases. It will also allow swifter and more accurate diagnosis of nvCJD, which can now only be confirmed by examination of the brain after death. A test using lymph or tonsil tissue is predicted within 4 to 6 months, and a blood test possibly in 12 months' time.

A test will also allow scientists to look at archive brain tissue from CJD victims who died long before BSE, which was first reported in 1986, emerged. This would confirm that nvCJD really is a new, and distinctive form of the disease.