Two major diseases are found in whitetail deer across the States. The first is Epizootic Hemorrghagic Disease or EHD. According to the Iowa DNR, this disease is "spread by a biting midge that causes high fever in infected deer and also causes the cell walls in their heart, lungs and diaphragm to weaken and burst." The most recent outbreak here in Iowa occurred in 2012 and 2013 across Southern and Eastern Iowa. Every year there are cases of EHD across the country, but some years are considered outbreak years. Sometimes it can take months for a virus to be transferred from a host to a deer. A female midge transfers the disease to a number of mammals when biting them to acquire blood for food. First they must bite an animal that carries the virus, then bite another animal. Cattle, elk, pronghorn, mule deer and many other large mammals can carry the disease but it never has the same impact as it does on whitetail deer. In 2013 over 1000 deer were reported dead in Iowa due to EHD.
Chronic Wasting Disease or CWD is a completely different disease that has only recently been found here in Iowa for the first time. In December of 2013 a deer that had been harvested in a state forest in Northeastern Iowa (where my Dad and I trout fish annually) was reported as having CWD. The Iowa DNR has this to say about CWD and its symptoms on their website:
"Chronic Wasting Disease (CWD) is a neurological disease affecting primarily deer and elk. An abnormal protein, called a prion, attacks the brains of infected animals causing them to lose weight, display abnormal behavior and lose bodily functions. Signs of CWD in deer include excessive salivation, thirst and urination, loss of appetite, weight loss, listlessness and drooping ears and head. It is always fatal to the infected animal".
The DNR in Iowa alone has tested over 60,000 deer since 2002 in an effort to catch the spread of CWD before it has time to grow. According to the Center for Disease Control their is no known harm done to humans through eating venison from infected deer, yet they caution hunters to wear gloves when dressing the deer out and recommend not to eat the spinal chord, eyeballs, or brain of infected deer.
Whether the disease is relatively old or new, the DNR is forced to keep a very close eye on the health of wildlife populations within our state. Taking protective measures before large breakouts occur can ensure the health of overall population of animals like deer for decades to come.
http://www.iowadnr.gov/Hunting/DeerHunting/CWDEHDInformation.aspx
http://gf.nd.gov/magazines/october-2013/bite-kills-ehd
How do they go about testing the deer?
ReplyDeleteFor CWD samples are sent to labs to be inspected. Often times deer that have died of EHD have very obvious symptoms across their body.
ReplyDeleteThere currently is no live testing method for CWD. Therefore, in areas where CWD is present, DNR takes brain samples from deer harvested during hunting seasons. Only two confirmed cases have been reported in the wild herd. However, multiple confirmed cases have come from deer farms within the state. Quarantine efforts, depopulation of positive deer farms, and wild herd testing are being implemented to keep the disease at bay.
ReplyDeleteEHD - Drought years often bring exposed mud flats where this tiny insect hatches and infects drinking deer.