Wasting disease may be here to stay: experts
Experts say it may not be possible to eliminate chronic wasting disease in deer and elk in Canada.
The fatal infectious disease is so well established in Saskatchewan and Alberta that the federal government and some provinces are rethinking how to deal with what is commonly known as CWD.
In 2005, Ottawa announced a national strategy to control chronic wasting disease in the hope of finding ways to eradicate it. Now the emphasis is shifting to preventing CWD from spreading, especially in the wild.
“We have to realize that we may not be able to eradicate this disease currently from Canada, given that we don’t have any effective tools, so we may be looking at switching from eradication to control,” said Penny Greenwood, national manager of domestic disease control for the Canadian Food Inspection Agency.
The agency says it is working with the provinces and the game-ranching industry to come up with a better plan, perhaps by next spring.
“We feel that the current program that we have had in place for chronic wasting disease ... is not effective in achieving its goals,” Greenwood said.
CWD is caused by abnormal proteins called prions and is similar to mad cow disease. There is no vaccine against it. Symptoms can take months or years to develop. They include weight loss, tremors, lack of coordination, paralysis and death.
Some scientists believe infected animals can pass the disease to other animals through saliva, blood, urine or droppings, or indirectly through prions in the environment. The prions can remain active in dirt for years.
There is no evidence the disease can affect people, but the food inspection agency recommends against eating meat from infected animals.
The latest report from the CFIA shows the disease is active in herds of deer on Saskatchewan game farms.
Scientists say the more pressing challenge is the growing number of infected wild deer and elk in Saskatchewan and Alberta. The disease has also been found in a moose. Researchers believe in one area of Saskatchewan, up to 50 per cent of the deer have chronic wasting disease.
“This is a disease that is now established in wildlife, and when you have a disease that is established in a wildlife reservoir, it is always extremely difficult to eliminate it,” Greenwood said.
B.C. and Manitoba have had no confirmed cases, but have put up billboards warning hunters not to bring deer or elk from other jurisdictions.
Scientists say a big challenge in tracking the spread of CWD is a lack of research into the disease and surveillance programs to track its spread. The federal government ended a program on March 31 that was established in 2005 called PrioNet Canada that was conducting research into CWD and mad cow disease.
Surveillance in the wild is difficult because there is no way to test live animals for the disease. Provincial governments rely on testing the heads of animals turned in by hunters. But in Saskatchewan and Alberta, the provinces where the disease is wellestablished, it is not mandatory for hunters to do that.