Fatal deer illness may threaten humans

• The continuing spread of a fatal wildlife disease in Alberta and Saskatchewan has a federal agency recommending a deer cull across a wide swath of the Prairies. And soon-to-bepublished research on chronic wasting disease has raised new fears about whether the illness could infect humans.

“I would say this question was answered with `yes,' ” said Hermann Schaetzl, a veterinary scientist at the University of Calgary.

Schaetzl's work was discussed in a recent report from the Canadian Agri-food Policy Institute, which advises the federal government on agriculture policy. Earlier this month, the institute concluded that in addition to human health concerns, the disease's spread over the last decade threatens Western Canada's agriculture, wildlife and food security.

“It's continuing to increase in its spread and the speed of its spread,” said Ted Bilyea, the institute's strategy officer.

Chronic wasting disease affects animals such as deer, caribou, moose and elk, attacking nervous systems with universally fatal results.

Like mad cow disease or Creutzfeldt-jakob disease in humans, it is caused by prions — misshapen proteins that can persist in the environment for up to a decade, able to transfer their shape to healthy proteins.

The report also discussed an experiment conducted on macaque monkeys, considered

IT'S EASY TO GO DOWN A DOOMSDAY SCENARIO BUT I DON'T THINK WE'RE THERE YET

the closest animal analogue to humans.

In 2006, German scientists began feeding macaques with meat from animals infected with the disease. Because it can take years for the disease to show, the monkeys weren't euthanized and tested until two years ago.

The first tests were ambiguous. But Schaetzl, who helped conduct confirmatory tests, said it became clear the monkeys had developed low-level infections.

“The more we did, the more we could confirm the macaques were infected.”

Although Schaetzl's work is still being peer-reviewed, it has been presented in conferences and is widely discussed among disease experts.

“I was shocked when we first learned of the results,” said Neil Cashman, a leading prion expert at the University of British Columbia.

Because the disease is so new and takes so long to develop, Cashman said there could already be people suffering from a human form of chronic wasting disease.

To keep tainted meat out of the food supply, Saskatchewan and Alberta require deer and elk farmers to test every animal that dies on their farms, including slaughtered animals.

There have been no cases of cattle catching the disease from wild animals.

“It's easy to go down a doomsday scenario but I don't think we're there yet,” said Dr. Keith Lehman, Alberta's provincial veterinarian. “I think it's low-risk.”

He points out macaques are still a different species.