CJD case rise not a blip, says scientist
An upturn in the number of cases of the human form of mad cow disease is not a blip but a "sustained pattern", says a scientist investigating the illness.
Professor James Ironside says analysis combining onset incidence with the number of deaths from variant CJD shows an increase of between 20% and 30% over the past year.
But the professor, from Britain's National CJD Surveillance Unit in Edinburgh, says it is still impossible to predict the scale of the epidemic.
He told the British Association science festival at Glasgow University: "My statistician colleagues all agree that this is a real observation. Moving from a flat pattern we're now seeing an upward change.
"This is a sustainable pattern. We've had blips before ... this is not a blip."
He added that two crucial questions have to be answered before such a forecast can be made about the scale of the epidemic.
These are the length of the incubation period of the disease and how it is affected by genetic susceptibility.
"It's impossible to say with any certainty what future numbers will be and over what time scale," he said.
"What we can say is that based on what we know we can dismiss the worst case scenarios. I think the scenario in which we see millions of cases is very unlikely."
