John Collinge of University College in London said that bovine spongiform encephalopathy and variant Cruzfeldt-Jakob disease, the human version of the disease, appear to have a long incubation period that could stretch to decades in some people, The Telegraph reported. He said BSE has not been seen in anyone younger than 12 even though a lot of children ate contaminated baby food as infants.

"I am afraid there are a lot more cases in the pipeline," he said.

BSE and related diseases are caused by prions, misshapen proteins.

Collinge has developed a new theory on how the disease becomes lethal. Researchers in the past believed the problem was the large clumps of misshapen cells that form in the brain, but Collinge thinks the lethal work may be done by smaller groups of protein.