West Nile Virus found in Michigan ruffed grouse

The Michigan Department of Natural Resources recently confirmed the presence of West Nile Virus in the state’s ruffed grouse population.

Five birds collected from August through October, including two found dead and three that were shot by hunters, were submitted for testing to the DNR’s Wildlife Disease Laboratory in Lansing, where the confirmation of West Nile Virus was made.

West Nile Virus is primarily transmitted to humans through the bite of infected mosquitoes. Most people infected with the virus do not show symptoms.

There is no evidence of human infection from eating properly cooked game that has been infected with West Nile Virus. As a general precaution, wild game meat should be cooked thoroughly, to an internal temperature of 170-180 degrees. Hunters should wear gloves when handling or cleaning game.

“We’ve had West Nile Virus in Michigan since 2002,” said Thomas Cooley, a DNR wildlife biologist and pathologist at the Wildlife Disease Laboratory. “It’s the first year that we’ve seen it in grouse.”

In addition to five ruffed grouse testing positive for West Nile Virus at the disease lab, five grouse were tested that did not have the virus.

This year, just over 200 animals have been confirmed with West Nile Virus from 60 of Michigan’s 83 counties, including all 15 counties in the Upper Peninsula. The ruffed grouse testing positive for the virus included two from Iron County and one each from Delta, Roscommon and Missaukee counties.

The Michigan Department of Health and Human Services said there have been 39 human cases of West Nile Virus reported in Michigan this year.

“We have received several inquiries from hunters about West Nile Virus and ruffed grouse,” John Pepin, DNR deputy public information officer, said. “We want to provide information on the virus to help everyone better understand its presence in Michigan and its connection to ruffed grouse populations.”

Al Stewart, DNR upland game bird specialist, said the primary question related to West Nile Virus and grouse is: what can we do to reduce the impact of this disease on grouse should we discover that it is a problem for Michigan grouse populations?

“The most important activity that can be done is to maintain and create vigorous young forest habitat (primarily aspen) that is composed of multiple age-classes,” Stewart said. “Michigan has high-value ruffed grouse habitat within areas of the state, especially in the Upper Peninsula. With West Nile Virus on the horizon, it will be even more paramount that we continue to focus on early successional forest management.”

Stewart said the DNR is very focused on maintaining healthy sustainable populations of wildlife.

“We are fortunate to be able to work through a variety of partnerships to achieve this goal,” Stewart said.