An outbreak of Epizootic Hemorrhagic Disease (EHD) is impacting deer primarily in south central Iowa with the largest concentration of infected animals being reported in Warren County.
EHD is caused by a virus spread by female midges that feed on deer. It causes high fever in deer and the cell membranes in their heart, lungs and diaphragm to weaken and burst. Infected deer are attracted to water to combat the fever and dehydration due to the hemorrhaging and usually die within a few days.
In dry years it can be worse as deer are more concentrated around water and since the disease is spread by a biting midge more deer can become infected. EHD remains active until rain disperses the deer, wind disburses the midges or a heavy frost kills them.
EHD is not related in any way to chronic wasting disease.
Losses due to EHD occur annually, usually at low levels and in localized areas. Current loss estimate is more than 400. The number is likely to increase as bow hunters head to the timber to begin placing their tree stands.