Bluetongue swells in local animal populations


Deer roam in the woods, and yards, of Whidbey Island in Washington.

The Washington Animal Disease Diagnostic Laboratory (WADDL) at Washington State has confirmed 48 accounts of bluetongue virus in domestic and wild animals were sent into the lab this year, the senior communications manager for the College of Veterinary Medicine said.

Charlie Powell said that of these animals, most have come from this region of Washington and Idaho, but a few have been sent into the lab from other states.

Bluetongue virus is carried by a species of biting gnat that is common in the Northwest said Steven Parish, professor of large animal internal medicine at the Veterinary Teaching Hospital. Early symptoms seen in animals affected by the virus may include fever, altered mood and a drop in energy. This virus primarily affects the lining of the blood vessels and causes internal bleeding, problems with circulation and possibly death, Parish said.

“The name comes from the cyanosis that occurs in the tongue of many animals affected by the disease,” Parish said.

The first local case of bluetongue sent in to the WADDL this year was in a whitetail deer from Latah County, which was discovered on Aug. 24, Powell said. The virus seems to be more prevalent in whitetail deer than mule deer, but this could likely just be because there are more whitetails in this area.

Bluetongue affects many wild and domestic animals such as deer, elk, cattle, sheep and goats, but it does not affect humans, Powell said. Sheep seem to be more vulnerable to the virus than cattle, but researchers aren’t sure why, although it could be due to both genetic and environmental factors.

Although this could be categorized as an outbreak, bluetongue virus happens annually, Powell said, and the public should not be overly worried.

“We’re certainly not seeing anything on an epidemic scale,” he said.

The reason there are more cases this year could be from the hot and dry summer that the region experienced, said Jennifer Bruns, Idaho Fish and Game regional conservation educator. The gnats that carry blue tongue virus live around water, so when the environment is dry and animals congregate around the water, one can expect to see an increase in the virus.

The virus should start to recede in coming months as the temperature drops, Bruns said.

“After we have a hard frost and the gnats die, the problem will start to go away,” she said.

Despite the increase in bluetongue cases, the virus has not had a significant effect on deer populations, and hunting seasons will not be changed, Bruns said. The Idaho Department of Fish and Game advises hunters not to shoot animals that appear sick, however, the meat of an animal with blue tongue virus is safe to consume.

*This article has been updated for clarity