In late summer and early fall, residents in Gilmer, Logan, Hampshire and Hardy counties started noticing dead deer.
The West Virginia Division of Natural Resources (WVDNR) received numerous calls and samples have been sent off to be tested. The culprit for the deceased deer is likely due to hemorrhagic disease.
So what exactly is Hemorrhagic Disease?
It is caused by either one of two closely related viruses. The epizootic hemorrhagic disease (EHD) virus and the bluetongue (BT) virus causes disease symptoms that are indistinguishable without lab testing so the general term hemorrhagic disease is used until test results verify which specific virus caused mortality. Both viruses are transmitted by tiny biting flies or midges. These biting midges are also known as sand gnats, flies and no-see-ums. Outbreaks usually occur in mid-August through October and then subside after freezing weather moves in and the biting flies die.
Hemorrhagic Disease is not transmitted from deer to deer. Only when the deer is bitten by the fly will it contract the disease. The EHD and BT viruses are more prevalent during drought years when deer are concentrated to limited water sources and numerous animals are more likely to be bitten.
Most of the deer found dead are usually near water sources. This is due to high fever caused by the disease and the deer trying to seek water to cool their bodies. EHD and BT also cause excessive hemorrhaging and even deterioration of blood vessels in the vital organs of infected animals. Other symptoms are swollen head, neck, tongue, or eyelids, and difficulty breathing.
Hemorrhagic Disease can cause death in 1 to 3 days but not all deer die from the disease. Some will survive for weeks and even months depending on how healthy a deer’s immune system is and how long it’s been infected. The infected deer will appear sluggish and even emaciated during this period.
There are some that survive and will actually become immune to the disease. Deer having survived will have evidence on their hooves. During the onset of the disease the hooves actually peel and split and the evidence is still visible during fall and winter when hunting season is in.
Lesions and ulcers found on the dental pad in the front of the mouth or on the tongue are visible signs that a deer has succumbed to hemorrhagic disease. There are outbreaks that occur almost every year somewhere in the southeastern US. Mortality rates are usually well below 25% of the infected population but in a few instances up to 50% or more have been documented in the southern states. To date there has not been a deer population completely wiped out by EHD or BT. It should also be noted that in areas with repeated hemorrhagic disease outbreaks deer population growth was not a limiting factor.
In West Virginia the first documented case of Hemorrhagic Disease occurred in 1981 in Ritchie County. That same year cases were found in Doddridge, Gilmer, Roane, and Tyler Counties. The next documented case happened in 1988 when at least 70 deer died in six counties (Barbour, Harrison, Roane, Upshur, Wood, and Wirt).
One of the largest outbreaks of EHD in West Virginia was responsible for mortality of several deer in the same areas of Hardy and Hampshire Counties in the summer and early fall of 1993. There were 228 dead deer found in the two counties in the Baker, Rio, Delray, Yellow Spring, Wardensville, and Lost River areas during that outbreak.
The 2016 outbreak were concentrated in isolated areas of the 4 counties affected. Only 2 deer were found dead and tested positive for EHD in Gilmer County but there may have been more that weren’t found. At least 40 dead deer were found in Logan County. The biggest outbreak occurred in the eastern panhandle of Hampshire and Hardy counties.
Several dead deer were reported by concerned citizens and the blue tongue virus is believed to have been the culprit in this outbreak. Hunters may notice fewer deer in these areas but hunting regulations should remain the same overall countywide. This same area of the eastern panhandle is the only place CWD has been found in the state as well and is by far more of a concern than last year’s hemorrhagic disease outbreak.