Who is to blame for mad deer?

• Author: McCombie, Brian

The helicopter rises up over the ridge line, the noise of the rotors scattering the targets below. But the snipers in the doorway already have their scoped, high-powered rifles locked in, and the bullets fly until the targets pitch forward, kicking and writhing in their death throes.

The latest battlefield description from Afghanistan? No. It's the next battlefield from the rolling, wooded hills near Madison, Wisconsin. The snipers are employees of the Wisconsin Department of Natural Resources. The targets? White-tailed deer, potential carriers of a deadly disease that may also infect people. It's called Chronic Wasting Disease (CWD), and it's steadily spreading across North America.

"CWD clearly originated in northeastern Colorado and now has ended up spreading far and wide into many states and two Canadian provinces," writes John Stauber, a Madison, Wisconsin, activist and co-author of Mad Cow U.S.A. (Common Courage, 1997), which examines England's Mad Cow nightmare and whether it could happen here.

The disease, he claims, is traveling faster and more effectively than nature could ever accomplish. He suspects this is due to the interstate transportation of game farm animals. And he blames the expansion of the disease on the game farm industry and state agricultural agencies that act more as game farm patrons than as regulators.

The outbreak is causing near hysteria in rural Wisconsin. The state plans to kill as many as 50,000 deer in the south-central part of the state, and deer hunters everywhere are left to wonder whether their venison is safe to eat. Research and anecdotal evidence suggests it is not. And that's scary news for the fourteen million deer hunters around the country.

Both Mad Cow and Chronic Wasting Disease are kinds of Transmissible Spongiform Encephalopathy (TSE). These diseases aren't viral or bacterial, yet somehow they transform or "fold" proteins in brain cells called prions. When enough infected prions deposit themselves in the brain, microscopic ruptures form in the brain cells. Prior to death, behavioral changes become apparent.

As the disease progresses, infected cattle become very agitated, kicking violently with no provocation. They also have trouble eating and swallowing, and usually lose weight. Similarly, deer with Chronic Wasting Disease stop eating. Their resulting emaciated state gives the disease its name. They also shy away from fellow animals, begin to slobber uncontrollably, and walk in circles.

As with all TSEs, Chronic Wasting Disease has no cure and is always fatal. The only way to test for it in elk and cattle is to kill them and examine brain samples under a microscope. A live test for deer was recently developed using a tonsil biopsy, but it's not yet clear how accurate this is.

The human version of TSE is called Creutzfeldt-Jakob Disease (pronounced Croytz-feld Yawkob). People with Creutzfeldt-Jakob Disease experience symptoms similar to Alzheimer's, including memory loss and depression, followed by rapidly progressive dementia and death usually within a year. While Creutzfeldt-Jakob Disease is rare (humans literally have a one-in-a-million chance of getting it), over the last few years three young deer hunters (from Utah, Oklahoma, and Maine) died of the illness.

Those deaths sparked an investigation by the Centers for Disease Control and Prevention, largely because the three hunters were younger than thirty, which is extremely rare for Creutzfeldt-Jakob Disease (sixty-eight is the median age for deaths resulting from the illness). While it found no connection to Chronic Wasting Disease-infected venison, the Centers for Disease Control and Prevention also had no way to test deer these hunters had...