Mad All Over

Dr. Thomas Pringle, a biochemical geneticist who consults for the Sperling Foundation, believes the disease emerged in Fort Collins thirty years ago, when deer were penned with scrapie-infected sheep. Scrapie is a wasting disease that has affected sheep for at least two centuries; many people believe England's BSE epidemic started after cows there were fed the remains of sick sheep. Since scrapie had existed for so long without harming humans--as far as anyone knew--the British government assumed that BSE was equally harmless. It was a disastrous assumption. "I place the blame squarely on DOW for ever allowing scrapie sheep to be closely quartered with wild game," Pringle says, "for waiting fifteen years to autopsy facility animals suspected of having scrapie, for releasing exposed animals back to the wild, for shipping sick animals to game farms and zoos long after they knew their incompetently managed facilities were contaminated, and for years of inaction and denial over the extent of the epidemic."

Pringle postulates a hypothetical worst-case scenario: "CWD spreads all up and down the Rocky Mountains, affecting many species of ruminants and carnivores. Over time, it then spreads to the rest of the West and to the rest of the country (and continent). It becomes established in domestic ungulates, first on common pastures on public land allotments, then more generally. Feeding, injection and in vitro studies suggest transmissibility to humans, and a new strain of CJD emerges among hunters in Colorado. Ranching interests then push for the systematic slaughter of all large wildlife in North America."

Pringle acknowledges that this X Files-worthy scenario compounds five hypothetical events: "that CWD will spread to other species in the wild in other locales; that it will be experimentally transmittable to sheep and cattle; that significant transmission to livestock occurs under field conditions; that livestock become infectious under short time scales; and that significant oral transmission will consequently occur in humans. I would guess the first is likely but the time scale uncertain," he says, "the second is nearly certain; the third is plausible at some level; the fourth is somewhat doubtful; and the fifth is a real unknown."

"We take a proactive approach," says the DOW's Malmsbury. "We tell people, don't take sick animals, and there are parts of the animal you should not eat--brain tissue, nervous tissue. But meat from wild animals is a health food compared to meat we get from grocery stores. It's literally prescribed by doctors on the Western Slope because it's low in fat and has no preservatives.

"We're not a meat-inspection program," Malmsbury continues. "We're a research program. If we find CWD, we do notify people, but there's no way we can go out and certify every person's animal for every disease, and we cannot notify immediately. There's no evidence to suggest that eating the meat of wild animals is going to be a hazard to human health, and no reason for people not to hunt."

Chris Melani, the Longmont man who shot a deer and ate its meat before finding out that it had CWD, is less confident. "As far as they know, it's not transmittable to cattle and humans," he says, "but you could turn that around and say as far as they know, it is." He adds, "I shot a one-year-old deer, and they say it doesn't affect young deer. When I shot it, it seemed perfectly healthy. Maybe a little stupid, but what do you expect from a little deer?"

For his part, Pringle expects trouble. "It is fair to say that a large-scale experiment is now under way on how efficiently CWD transmits to humans," he says.

"This wasting disease is higher among deer and elk in Colorado than BSE ever was among cows in England," says Jean Halloran, director of the Consumer Policy Institute of the Consumers Union. "It's huge. And I don't see a concerted effort to assess whether this might be a problem for human health."

In 1997, the U.S. Food and Drug Administration came out with regulations forbidding the use of most mammal protein in feed for cows, sheep and goats. But blood, gelatin, milk, and pig and horse protein, as well as food scraped off diners' plates in certain restaurants and institutions, were exempted from the ban, according to Rhodes's book. Animal feed can also include euthanized cats and dogs, mink carcasses and poultry manure. Pet animals can get transmissible spongiform encephalopathies, and so can mink. Deer remains--roadkill and hunters' waste products, including brains and spinal cords--go into pig feed. Although pigs don't seem to get these diseases, they're usually slaughtered before a disease could manifest itself. In turn, pig carcasses are rendered for cattle feed.

"We should have a complete mammal-to-mammal ban," says Halloran. "I'm especially concerned about a new product for feeding calves. Freeze-dried blood. It's not even rendered. I've given up red meat since I've been on this project.

"If you have a taste for red meat," she adds, "my recommendation is to eat it in big chunks. That's better than something like frankfurters. Muscle meat has a very low level of infectivity compared to other parts of animal. It's the nameless organs that you want to avoid."