A UK scientist, who advises the government on BSE (Bovine Spongiform Encephalopathy), says that the incubation period of variant CJD in humans may be as long as 30 years.

Professor John Collinge, a member of the Spongiform Encephalopathy Advisory Committee (SEAC), said there could be a scenario where eventually thousands of people could die from the human form of mad cow disease. His colleague Roy Anderson revealed that as many as 130,000 people in Britain could die from vCJD.

It is thought that vCJD is contracted through eating meat contaminated with BSE.

Collinge' comments come only days after the publication of the official report into cluster of vCJD in the Leicestershire village of Queniborough. The report in that inquiry estimated that the incubation period of vCJD was likely to be between 10 and 16 years.

Speaking on the BBC's Today programme on Thursday, Professor Collinge said: "For me the main finding from this report is that the significant exposure appears to pre-date 1985. The cases we are seeing at the moment are by definition those with the shortest incubation periods. The average incubation period could well be in the region of 30 years."