Suspected EHD cases reported in Illinois deer during 2017
Suspected EHD (Epizootic Hemorrhagic Disease) cases were reported again in Illinois in 2017, but in low to moderate levels.
A total of 66 reports were received from concerned landowners and hunters totaling 169 deer from 32 counties, the Illinois Department of Natural Resources, IDNR, reported.
In comparison, 2012 was the worst year for EHD in Illinois with 2,968 dead deer reported to IDNR from 87 counties.
IDNR shared that there were three reports involving seven deer in Union County.
Statistics also showed one report involving eight deer in Alexander County, three reports involving four deer in Johnson County and two reports involving seven deer in Williamson County.
EHD is a viral disease, spread by biting gnats, which can cause high fever and severe internal bleeding in deer.
While often fatal to deer, EHD is not hazardous to humans or pets.
EHD-like symptoms in cattle have been reported where EHD has been confirmed in deer, IDNR noted. Cattle can be successfully treated with medications.
EHD is often confused with bluetongue, a similar disease that can affect sheep and cattle.
EHD was reported at low levels in the southern third of the state, as well as in west central Illinois extending up the Illinois River valley.
A more intensive outbreak was reported in the west central Illinois county of Pike (80 cases).
EHD does not impact deer populations evenly across the landscape, IDNR reported.
A mixture of deer combined with the presence of the virus and midges (biting gnats) that transmit the disease between deer are necessary for an EHD outbreak to occur.
Heavy deer mortality can be observed on one farm, while the farm down the road will be hardly affected.
EHD affects bucks as well as does, adults as well as fawns and yearlings, though individual deer vary in their susceptibility to the virus.
Some deer become infected and will be dead within 48 hours, while other deer will be minimally affected. Survivors of infection develop immunity to the virus.
Dead deer are often found near water sources such as lakes, ponds or streams, though a deer carcass found away from water is also likely to have succumbed to EHD.
EHD-related mortality occurs every year, but becomes more severe during droughty conditions.
Limited water sources concentrate deer near exposed mud flats resulting from receding water levels.
Midges hatch from these exposed muddy areas, resulting in abundant insect populations.
IDNR reported there is no effective management treatment for the disease. EHD outbreaks end when a heavy frost kills the midges necessary for transmission.