A disease more common in Southern states might now be impacting deer in the Sauk Valley.
Conservation authorities say that two white-tailed deer recently found dead in the Oregon area likely succumbed to epizootic hemorrhagic disease (EHD).
“The circumstances strongly suggest EHD,” said Doug Dufford, Wildlife Disease and Invasive Species Program manager for the Illinois Department of Natural Resources.
Conservation Police Officer Steve Beltran said the first deer, a buck, was discovered Sept. 8 by a fisherman on an island in the Rock River near the boat launch at Castle Rock State Park south of Oregon.
The second, a doe, was found Sept. 15 along a road northeast of Oregon.
Dufford said the first had been dead too long for testing to be conclusive, but tissue samples from the second have been sent to a lab. Results are not yet available.
He said dying near water is typical of deer suffering from EHD because the disease causes them to have a fever. The animals go to the water to drink and to cool off.
Dufford said EHD often is confused with blue tongue disease because the symptoms are nearly identical. Both are spread by the bite of a midge, a small two-winged fly.
The EHD virus causes deer to hemorrhage internally, Dufford said.
It does not usually occur this far north.
“We’ve only recently seen it in the northern part of the state,” Dufford said. “It’s more common in the Southern states. It’s not a big deal there because the deer have developed immunity to it.”
Dry conditions the past two summers may be a major reason why EHD has appeared in this part of the state, he said.
“EHD is transmitted by midges, and they typically hatch in mud flats along lakes and rivers,” Dufford said. “With the water receding, more are hatching. When you have high water there are fewer hatches.”
The drought conditions also mean watering holes are drying up and more deer are concentrated in the areas when the midges are hatching, he said.
Humans are not susceptible to EHD. The threat to livestock is not fully known.
Not all deer die of the disease. Some develop resistance to it and survive.
“The others die within a day or two of getting it,” Dufford said.
EHD cannot be spread from one deer to another, he said. It requires the midge as an intermediate host.
Because of that, the first hard frost of the season will kill the midges and put an end to the problem, for this year, he said.
The outbreak does not pose a threat to the deer population, Dufford said.
“It’s not something people need to be panicky over.”
However, he advised the public to let officials know when they see sick or dead deer that appear otherwise healthy, especially if the animals are observed near water.
Call Dufford at 815-535-2875, or the Illinois State Police at 815-632-4010 and ask for a conservation officer.