Mad Cow Disease May Have 30 Year Incubation Period
January 02, 2008
The findings of the inquiry into a cluster of variant Creutzfeldt-Jakob disease (vCJD) cases -- the human version of mad cow disease -- suggest the fatal disease has an average incubation period of 30 years and may claim thousands or tens of thousands more victims.
The inquiry report into five deaths in the English village of Queniborough, Leicestershire, blamed specific butchering methods for contamination of meat with bovine brain and estimated an incubation period of the disease between 10 and 16 years.
But Professor John Collinge, a member of the Spongiform Encephalopathy Advisory Committee (SEAC), which advises the government on mad cow disease or bovine spongiform encephalopathy (BSE), told BBC Radio: "For me the main finding from this report is that the significant exposure appears to pre-date 1985.
"That sent a little chill down my spine, certainly. It fits with our estimates that we have been making of the likely incubation periods of BSE in humans."
Professor Collinge, a specialist in prion protein diseases at St. Mary's Hospital, London, pointed out: "The cases we are seeing at the moment are by definition those with the shortest incubation periods." Prions are the infectious proteins thought to cause both BSE and vCJD.
Therefore, the average incubation period could "well be in the region of 30 years".
He added: "Unfortunately what follows from that, since the exposure of the population after 1985 was very much larger than that that preceded it, (is that) many more cases must be in the pipeline. "We may see thousands, or tens of thousands."
London, England March 22, 2001 Reuters Wire Service