Tuesday, May 15, 2007

Chronic Wasting Disease

A testing program in West Virginia has detected three white-tailed deer with chronic wasting disease. The three deer were in a containment area for disease monitoring in Hampshire County. Chronic wasting disease was first found in West Virginia in 2005.

CWD is a neurological disease caused by a mutant protein called a prion. It is in the same family as mad cow disease, scrapie, which affects sheep, and Creutzfeldt-Jakob disease, which attacks humans.

The prion riddles the brains of deer and elk with microscopic lesions. When the animals become infected, they stagger, slobber and show little fear of humans. They gradually lose the ability to care for themselves.

The first case was detected in Colorado in 1967 and spread east, reaching Wisconsin in 2002. It baffled biologists when it jumped the Mississippi River and infected deer in Illinois. Then two years ago, CWD was detected first in upstate New York and then West Virginia....

Maryland, which has a population of about 265,000 deer, tests hundreds of bucks and does every hunting season, with biologists and veterinarians taking brain stem samples at taxidermy shops. Officials also have taken steps to eliminate captive deer herds, since penned, domesticated animals are considered one of the primary entry points and spreaders of the disease.
For more on chronic wasting disease, see the fact sheets from the USGS and USDA, as well as its Wikipedia entry.