Bent Out Of Shape: Could A Mysterious Animal Epidemic Become The Next Mad Cow?

By Rae Ellen Bichell
 
Chronic wasting disease is crippling deer populations in the Mountain West, around the country and in bordering Canadian provinces. It's not a bacterium or a virus or even a fungus, but caused by something called a prion, a type of protein that all mammals have in their bodies. From the Mountain West News Bureau and published in collaboration with High Country News, this four-part special report examines the disease's origins and impact, and a global effort to stop it from spreading.
Part 1: A Mysterious Animal Epidemic
...The mountain lions know that something is wrong. A number of years ago, Swanson and her colleagues studied which deer mountain lions prefer to attack.
"The mountain lions were definitely preferentially selecting deer that had chronic wasting disease over those that were negative," she says. "And for most of the ones that they had killed, we had not detected any chronic wasting disease symptoms yet. So certainly the lions were able to key in on far more subtle cues than we were."
Unlike us, the lions know that while a deer might look sleek and alert, it's actually a ticking time bomb. That's one of the weird things about this disease. It isn't like the usual viral or bacterial illness. The infection can sit in a herd, crawling from animal to animal, for years before people notice anything is wrong.
"Through time (it) degrades, essentially, their brain tissue," says Swanson.
Then, things can go downhill fast. Swanson says it could be a matter of weeks before buck 46 or doe 22 starts to droop and drool, as an infection gnaws holes into its brain.
"That seems to happen pretty rapidly," she says. "To our eyes they look fairly healthy and within a number of weeks they reach that point and then they're gone."
Scientists have called chronic wasting disease a nightmare and a state of emergency. Lawmakers are calling it a crisis. Lately, the media’s been calling it "zombie deer disease." There are at least three bills being considered at the national level right now to combat the disease...

READ PARTS 1-4