BETHESDA, Md. (Reuters Health) - Food and Drug Administration (FDA) advisers on Friday said there was no evidence humans could be infected with a brain-wasting disease that has affected deer and elk.
Some free-ranging deer and elk in small areas of Colorado, Wyoming, and Nebraska have developed a fatal illness similar to mad cow disease, called chronic wasting disease. The disease, a spongiform encephalopathy, has also been seen in elk raised on farms across the US.
The concern is that people who process or eat meat from diseased elk or deer might themselves become sick, as has been seen in people who have eaten infected beef in Europe. Elk antlers--in powdered form--are also used in some countries as an aphrodisiac.
But after hearing from elk breeders and processors, wildlife management specialists, the Centers for Disease Control and Prevention (news - web sites), and the US Agriculture Department, the FDA's Transmissible Spongiform Encephalopathies Advisory Committee ruled there was no evidence that chronic wasting disease had jumped from deer and elk into humans.
The disease was first seen in captive deer in 1960, and has been tracked more intensively by agricultural authorities in the wild and on farms since the mid-1990s, said Michael Miller, a wildlife veterinarian with the Colorado Division of Wildlife.
Intensive sampling of wild deer and elk shows the syndrome has not spread beyond the highest prevalence areas in northeastern Colorado, southeastern Wyoming and a tiny corner of southwestern Nebraska, said Miller. The epidemic there seems to sustain itself year after year, he said.
The wasting disease was first seen in farmed elk 11 years ago, Miller said. The American Elk Breeders Association is developing a plan with the US Agriculture Department to contain epidemics and monitor herds for future outbreaks, said Glen Zebarth, a Montana veterinarian and representative of the group. The program, which would cull out and destroy infected animals, would also apply to deer farms.
Eighteen states have already made the program mandatory for farmers.
About 110,000 elk reside on US farms. Most are not slaughtered, so exposure risk through consumption is low, he said, adding that most deer and venison in American restaurants is from New Zealand.
There is a fear that hunters may be risking illness by eating infected deer and elk meat.
Suspecting a link, the CDC since 1997 has investigated three unusual cases of Creutzfeldt-Jakob disease, an illness similar to mad cow disease and chronic wasting disease. The two men and one woman were all young--under 30--which is unusual for CJD. All died shortly after diagnosis.
Ermais Belay, a CDC epidemiologist, said all three had eaten deer and elk, but that the meat did not come from wasting disease endemic areas. After brain tissue sampling and genetic and diagnostic testing of the CJD strains, the CDC concluded that ``there was no strong evidence for a causal link between chronic wasting disease and CJD in these patients,'' said Belay.
The panel agreed.
``I think the prime danger of chronic wasting disease is in a cross contamination,'' that is, to another animal species, said chairman Paul Brown of the National Institute of Neurological Disorders and Stroke.