State wildlife and health officials are reminding deer hunters to take proper precautions when handling deer carcasses following the discovery of anthrax in dozens of cattle and two deer in northwestern Minnesota.
As of Aug. 31, approximately 70 dead cows had tested positive for anthrax at 18 sites among Marshall, Roseau and Kittson counties. Also, a dead deer found in Kittson County and another in Roseau County both tested positive for anthrax. Though deer likely have contracted anthrax before, these are the first confirmed Minnesota cases of deer contracting the disease in recent history.
Minnesota's archery deer season opens Sept. 15. Although the chances of a hunter contracting anthrax from venison are slim, state wildlife officials believe that it's possible for a deer hunter to encounter a diseased deer. State health officials emphasized that routine precautions for the safe handling of deer meat should greatly reduce any small risk that exists.
One of the oldest diseases known to humans, anthrax is caused by a type of bacteria known as Bacillus anthracis. When exposed to air, anthrax bacteria produce spores that can survive for many years in soil and then grow rapidly in warm, wet conditions. Animals become infected when bacteria or spores enter the body. Outbreaks occur usually in late summer during rainy weather.
Any warm-blooded animal can contract the disease, but it is most common in cattle and sheep. Outbreaks among cattle occur occasionally in Minnesota.
The risk of anthrax infection in humans is remote. No human cases have been reported in Minnesota for at least 20 years. When people do become infected, it is almost always because bacteria or spores have entered the body through a cut or an open sore. Most anthrax infections in humans are easily treated with antibiotics.
Because they may be handling the carcasses of infected animals, deer hunters may face a slightly higher-than-normal risk of infection - although the risk is still extremely low, say state health officials. In Minnesota, infected deer are most likely to be found in Marshall, Roseau and Kittson counties.
It is highly unlikely that hunters will actually encounter a diseased deer, said Joe Marcino, Minnesota Department of Natural Resources (DNR) pathologist, because any deer that do become infected will get sick and die within 24 hours. Marcino added that the bacteria don't grow in cool weather, so the likelihood of deer contracting the disease will greatly decline as the deer hunting season progresses.
"Once the temperatures drop below 59 degrees, there's no growth of Bacillus anthracis," he said.
Hunters and others spending time in the outdoors in the affected counties can reduce risk by taking the following precautions:
Minnesota health and wildlife officials continue to monitor the anthrax outbreak, and will advise hunters of any new developments that may affect their health and safety.