Bluetongue Disease a Concern in Northeast

By The Omak-Okanogan County Chronicle

Hunting seasons may not be affected, but white-tail deer in the northeast portion of the state, including Ferry County, may be vulnerable to an outbreak of bluetongue disease.

The state Department of Fish and Wildlife notified the public Friday of the outbreak of the disease, transmitted by biting gnats (also known as midge and officially called Culicoides sonorensis) at water sources where deer congregate during dry conditions.

Although drought conditions exist in neighboring counties, including Okanogan County, several reports were received by DFW of suspected deaths from bluetongue or EHD (epizootic hemorrhagic disease ) in Ferry, Asotin, Columbia, Garfield, Lincoln, Pend Oreille, Spokane, Stevens, Walla Walla and Whitman counties.

"Always possible," regional DFW director Jim Brown said of the disease spreading. "Only time will tell.

"I think it is mostly in the whitetail population right now and Ferry County has a large number of them."

Every year in late summer and early fall, some white-tailed deer are lost to bluetongue and a similar virus known as EHD, state DFW veterinarian Kristin Mansfield said.

She said the department does not know precisely how many deer have been affected, but reports are more widespread and numerous than in the past, probably because of the severe drought across the region.

State DFW wildlife managers said the emergence of the disease will not affect this year's hunting seasons. Archery deer hunting season is under way now, and muzzleloader and modern firearm seasons start next month.

State DFW will continue to monitor effects of the disease until it subsides. Mansfield said outbreaks usually end with the arrival of colder, wetter weather, when deer move away from gnat-infested areas, or by the first hard frost, which kills the disease-carrying gnats.

Deer suffering from hemorrhagic disease may develop high fever and bloody noses and are often found lying down. They are sometimes discovered in or near water and allow people to approach closely.

A swollen and dark tongue usually indicates bluetongue virus disease, but any hemorrhagic disease has the potential to produce blue tongue in deer.

"This disease is a virus and it is transmitted to deer and other ruminants (cattle are mildly affected) by an insect, a biting midge of the genus Culicoides," said Lloyd Fox, big game program coordinator for the Kansas Department of Wildlife, Parks and Tourism.

"Kansas, like the Northwest, is in a hot, summer drought that's produced two cases of the disease.

"Hemorrhagic disease hit whitetails extremely hard in 2012, the latest in a recent string of notable years for outbreaks," Quality Deer Management Association said. "The disease (mostly strains of a virus known as epizootic hemorrhagic disease or EHD, but which also includes the closely related bluetongue virus) is striking areas that were previously unaffected, or rarely affected.

"In these areas it is having its worst impact, because whitetails have less history with the disease and therefore less acquired resistance to the viruses."

"HD is a traditional disease of deer and while there may be high numbers of dead deer in a particular area, the deer herd will generally repopulate the area within a few years," Fox said.

State DFW urges people who observe suspected bluetongue or EHD in white-tailed deer to call state DFW's eastern regional office in Spokane at 509-892-1001 or the department's dead wildlife hotline at 1-800-606-8768.

Bluetongue and EHD are not spread from deer to deer, and are not transmissible to humans, the state said.

Still, state DFW discourages hunters from shooting and consuming animals that are obviously sick. Other wildlife species, including mule deer, are rarely affected.

Symptoms in the early stages include lethargy, disorientation, lameness, or unresponsiveness to the presence of humans. Later signs include excessive salivation or foaming at the mouth and a swollen tongue.

Mansfield said the disease often kills deer so quickly - within a day or two - that their bodies remain in good condition, while others may not die immediately but stop eating and become emaciated. She said the incubation period for these diseases is five to 10 days, so afflicted deer may be observed for a couple of weeks after the first hard frost of fall.