Epizootic Hemorrhagic Disease, or EHD, is a disease that mainly affects white-tailed deer in the United States. According to a report put together by the College of Veterinary Medicine at The University of Georgia, the disease is caused by viruses in the epizootic hemorrhagic disease and bluetongue virus groups. Because clinical disease produced by EHD and BT viruses is indistinguishable, EHD and even bluetongue are umbrella terms used to describe the current outbreak even though the specific virus to blame is unknown.
EHD is the most common occurring viral disease of white-tailed deer in the United States. While it can affect mule deer, bighorn sheep, elk and pronghorn in South Dakota, it primarily impacts the whitetail herd.
The southeastern portion of the United States has EHD outbreaks every year with relatively few animal losses. In the northern plains, we usually see minor disease losses, but in some years, such as in 2012, losses can be significant.
The disease is transmitted by biting flies. These flies are commonly known as biting midges but are sometimes called sand gnats, sand flies, no-see-ums and punkies.
The disease usually affects deer herds in the Dakotas in late summer or early fall. The seasonal occurrence of EHD coincides with periods of biting midge abundance, which apparently has been higher this year thanks to the dry conditions. The onset of freezing temperatures mortally affects the midge populations and usually brings a sudden end to EHD outbreaks.
How the viruses persist through winter is not active is not clear. However, it is believed that in areas with a mild climate, midges may remain active and locally support year-round virus transmission.
According to the Univ. of Georgia report, clinical signs of infection are highly variable and many infected deer appear normal or show only mild signs of illness. Initially, animals may be depressed and feverish, with a swollen head, neck, tongue or eyelids accented by breathing difficulty. Deer may die within one to three days. More often, deer survive longer and may become lame, lose their appetite or reduce their activity.
The South Dakota Game, Fish and Parks Department has been monitoring die-offs of white-tailed deer across portions of the state and must make adjustments to some West River deer hunting units.
In response to the disease, all unsold licenses will be removed from the following deer hunting units for the West River deer season: Bennett County: 11A-09 and 11B-17; Gregory County: 30A-19 and 30B-19; and Jackson County: 39B-09. In addition, 200 licenses will be removed for Meade County: 49B-09.
“As the department continues to monitor the outbreak of EHD over the next couple of weeks, we will provide additional recommendations to the Game, Fish and Parks Commission at its October meeting to address East River deer units,” said GFP Secretary Jeff Vonk. “Currently, the department plans to recommend that the commission remove all unsold licenses in Bon Homme, Hutchinson, and Yankton counties and make significant reductions to leftover licenses in Brule and Charles Mix counties for the second draw of the East River deer season. Between now and the next commission meeting, we will continue our surveillance efforts with the possibility of additional license reductions.”
Aside from conducting ground surveillance and collecting reports from the public, GFP is also using aerial flights to help determine the severity of deer mortalities.
“Reports of dead deer are coming from across the state, and in some instances landowners are telling traditionally hosted hunters that opportunities will be limited,” Vonk said. “With that in mind, GFP is notifying deer hunters that they can voluntarily return a deer license for any season prior to the start of that respective season and receive a full refund.”
Hunters desiring a refund for a deer license should send their license, including all associated tags, to: SDGFP Licensing Office; 20641 SD Highway 1806; Fort Pierre, SD 57532. SDGFP continues to ask individuals who see sick deer or find dead deer to contact their local conservation officer or call the Pierre office at 605-773-5913.
However, hunters should remember that EHD is common in white-tailed deer and occurs each and every year. It's paramount to understand that EHD is not infectious to humans. While it's a general rule of thumb that deer with generalized disease are not suitable for consumption, the facts remain that humans are not at risk if they handle infected deer, eat venison from infected deer or are bitten by the midge flies.
Use common sense and if a deer looks unhealthy, don't shoot it. Fear of the disease shouldn't have any bearing on how much time you spend chasing whitetails this year.
