TORONTO (CP) - A neurologist at the University of Toronto says a vaccine for mad cow disease could be a year away.

Neil Cashman, a professor of medicine, says he has discovered a way of identifying an antibody specific to an abnormal protein called the prion - a feat scientists have been trying to accomplish for 15 years. The prion is responsible for the spread of mad cow disease and its human form, Creutzfeldt-Jakob disease.

"We should have an answer on whether this can block prion replication in about a year," Cashman said Sunday.

"At that point, if everything looks good, there will be a move to larger animals including sheep and cattle, and some real heavy work to see if it could be applied to humans."

Cashman's research team, which included colleagues from the United States and the United Kingdom, found that prions propagate through a process akin to crystallization, unlike the growth of viruses and bacteria, which depend on nucleic acid.

He said this allowed for the deliberate manipulation of prions, which in turn could lead to a vaccine and the eventual eradication of mad cow disease.

"It may be possible to block the prions from recruiting . . . and chewing up the brain as they go," he said.

"You could screen the 10 million cattle in Canada for cattle that are incubating mad cow disease, so you would have a way of identifying only those cattle that are going to come down with the disease rather than just recognizing them when they become symptomatic . . . which would improve the safety of the food supply, hopefully the world around, not just Canada."

Calves could be immunized against prions, preventing them from ever coming down with mad cow disease. But the finding would not likely help cattle currently being slaughtered, Cashman said.

About 1,000 cattle have been slaughtered in Canada since a single case of mad cow disease broke out in Alberta last month.

While it's possible for a vaccine to be developed within a year for livestock, a counterpart for Creutzfeldt-Jakob disease is still far off.

"If there's an effective vaccine for mad cow disease it'll be applied immediately. In humans though, it can take five to 10 years to get something approved for use," Cashman said.

The research team's discovery could have applications in the treatment of other degenerative illnesses including Alzheimer's, Parkinson's and Lou Gehrig's diseases, Cashman added.

"That, of course, is a gleam in our eyes at this point."

The findings were reported online in the June 1 edition of scientific journal Nature Medicine.