Amid widespread reports of dead deer being found around the state, DNR deer management biologist Chad Stewart said recently that laboratory tests have identified a deadly virus as the culprit in four counties.
EHD, or epizootic hemorrhagic disease, was confirmed in samples collected from dead deer in LaGrange, Miami, Morgan and Sullivan counties. In addition, the State Board of Animal Health has identified EHD at captive cervid facilities in Putnam, Adams, Marshall and Vanderburgh counties and in cattle in Ripley County.
"Our list is over 40 counties now where it has been reported or suspected in deer," Stewart said.
Although citizen reports to the DNR of dead deer were consistent with EHD episodes of past years, Stewart was cautious until lab tests were complete in order to rule out the possibility of bluetongue, a disease similar to EHD that affects mainly sheep but also cattle, goats, deer and other ruminants.
The final lab report was received this week from the Southeastern Cooperative Wildlife Disease Study at the University of Georgia. Other samples were tested at Purdue University.
The tests confirmed two strains of the virus: EHD V-2 and EHD V-6.
"Basically, 10 years ago we didn't have the EHD V-6 strain in Indiana," Stewart said. "It's just recently been documented, so it's still relatively new on the landscape. It may be an explanation for some of these harder hit pockets."
In addition to the counties where EHD is confirmed, Stewart said the virus is suspected in reports of dead deer in Adams, Bartholomew, Brown, Cass, Carroll, Clay, Crawford, Daviess, Dearborn, Decatur, Delaware, Dubois, Elkhart, Fayette, Franklin, Gibson, Hendricks, Henry, Jay, Jefferson, Jennings, Johnson, Knox, Lawrence, Marion, Monroe, Ohio, Owen, Parke, Perry, Pike, Porter, Posey, Putnam, Randolph, Ripley, Shelby, Spencer, Steuben, Switzerland, Tippecanoe, Union, Vermillion and Warrick counties.
"If it's not as bad this year as it was in 2007, it's getting close," Stewart said, noting an outbreak five years ago in which EHD was reported in 59 Indiana counties and confirmed by lab tests in 17. "We did a lot more testing and confirming in 2007. This year we're lying back because the tests are so expensive and we know what it is."
EHD is a non-contagious virus that likely affects white-tailed deer every year. Severity and distribution of the disease is highly variable and unpredictable. It typically occurs during late summer and early fall. There is evidence that outbreaks may be worse during drought years.
EHD is not transmitted from deer to deer but instead by flies commonly known as biting midges. Deer infected with EHD may appear depressed or feverish. They often seek comfort in or around water. Other signs may include blue-tinted tongue or eyes, ulcers on the tongue, sloughed hooves, or an eroded dental pad.
Hemorrhagic disease is often fatal to deer, but some will survive the illness. Not every deer will contract hemorrhagic disease, which can be present or absent in any area. Death losses during an outbreak can range from negligible to greater than 50 percent. Severe outbreaks rarely occur in subsequent years due to immunity gathered from previous infections.
The onset of freezing temperatures often brings a sudden halt to EHD outbreaks.
EHD is confirmed or suspected this year in at least 10 other states: Illinois, Iowa, Michigan, Missouri, New Jersey, North Carolina, Ohio, Pennsylvania, South Dakota and Wisconsin.
Humans are not at risk for contracting hemorrhagic disease.