Chronic wasting disease CWD (** BSE or CJD? the effect to the brain is the same) has infected more than 18,000 wild Deer in parts of the US.

LAST YEAR (2002), the Wisconsin Dept of Natural Resources instituted special hunting periods to try and wipe out more than 12,000 deer in its area. This was an attempt to keep CWD from infecting another 1.6 million deer nationwide.
The disease was first reported near Fort Collins Col
back in 1967. By 1970 the Fort Collins facility became a CWD deathtrap, since 90% of the deer that stayed there had to be euthanised.
In 1980 the scourge emerged outside Colorado, and was spreading.
How ? Well nobody really knows. In the wild deer's case, it was obviously NOT being spread by foodstuffs. Could the prion be spread by the Deers urine? During the rutting season bucks lapup the urine of dozens of females does to find out who is coming into heat. Both Deer and Elks greet each otherby licking each others mouths and noses.
By 1985 vetenarians discovered CWD in herds of free ranging deer and elk.
The diseases persistence has permantly contaminated
approx 15,000 squ miles in north-eastern Colorado, south-eastern Wyoming and southwestern Nebraska.
In 2002 some 20 ranches, (of the estimated 8,000 ranches -they farm hundreds of thousands of deer and elk for their meat and antlers), -found they had Deer and Elk falling ill.

Then the US Centers for Disease p[revention and Control decided to see whether CWD posed a threat to humans similar to CJD.
They found at that time, three....a 28 year old cashier who died in 1997: she had eaten Deer and Elk as a child, from her fathers hunts in maine.
The second was a 30 year old salesman from Utah, who had been hunting regularly since 1985, who was diagnosed and died in 1999.
The third was a 27 yr old truck driver from Oklahoma who died in 2000, he had harvested deer at least once a year.
Six other patients (all middle aged) are presently under investigation.

Although many States have uncovered CWD, other States are now looking darn hard, but have not yet found it.
Sadly it seems that the only way to save the deer is to shoot them, thousands of them, and then burn the carcasses.

I have precis the above from a four page article that appeared in the Scientific America (June 2003).
and elsewhere at:-
http://www.sciam.com/article.cfm?articleID=00028CB6-F60A-1EBB-BDC0809EC588EEDF
Also
www.thepathologicalprotein.com
and
US Dept of Agriculture website at:-
www.aphi.usda.gov/lpa/issues/cwd/cwd/html