HEBDEN BRIDGE, U.K.--A recent sharp rise in the number of deaths from variant Creutzfeldt-Jakob disease (vCJD) in Great Britain has caused concern that a long-feared epidemic of the deadly brain disease is impending. But the numbers may be a statistical fluke, scientists write in tomorrow's issue of The Lancet.
Researchers agree that vCJD, to which some 39 Britons have succumbed since 1995, can be caused by eating meat from cows with Bovine Spongiform Encephalopathy (BSE), better known as mad cow disease. Millions of British people may have been exposed to meat from infected cows during a BSE outbreak that peaked in the late 1980s; but nobody knows how many are likely to become vCJD victims, or how long the disease will take to develop in the average patient.
So far, the numbers have been reassuring: In each of the first three quarters of 1998, only two deaths were reported. But in the final quarter of '98, the number suddenly jumped to nine. That may be a coincidence, a team of scientists led by Robert Wills from the CJD Surveillance Unit in Edinburgh write in their analysis. But it could also signal the beginning of a larger rise, adds one of the authors, Simon Cousens from the London School of Hygiene and Tropical Medicine. "I don't want to prejudge the issue," says Cousens, "but I wouldn't be surprised if it was the start of an upward curve." It's not likely that the apparent rise is due to increased vigilance among doctors, the team writes, because vCJD has been a high-profile disease for years.
Scientists and the public alike are now anxiously awaiting more recent data. So far, there has been only one confirmed vCJD death in the first quarter of 1999, but that means little, because it usually takes months for confirmed cases to trickle in. It will be 6 to 9 months before there is more certainty, says Cousens. "Certainly I am concerned by the numbers," says John Collinge, head of the department of neurogenetics at Imperial College School of Medicine in London.