More EHD deer
in Clayton County
By Ted Pennekamp
Deer hunters in Clayton County, Iowa found several more deer carcasses suspected to have been infected with Epizootic Hemorrhagic Disease (EHD) this past deer season. Many of the EHD carcasses were found in the Marquette-McGregor area.
Iowa DNR deer, forest and wildlife biologist Tom Litchfield said that the deer carcasses are probably old carcasses because the midges that carry and spread EHD die off once the temperature gets too low, especially below freezing.
Previously, 25 dead whitetail deer were reported in Clayton County. That number has now risen to 44. It stands to reason that a large group of hunters “driving” deer through the woods will come across more carcasses, said Litchfield, who estimated that the number of dead deer reported is probably 10-20 percent of what actually occurred. Many carcasses are never found and many are not reported.
Litchfield said that the 44 reported in Clayton County is the most ever. Due to unusually high temperatures and dry conditions, EHD infected deer were found much farther north in the state of Iowa than in the past.
Litchfield noted that because of the drought of 2012, there were approximately 3,000 EHD-infected dead deer reported statewide in Iowa that year. In 2013, there were 1,053 dead deer reported statewide. These deer have been reported in 54 of the state’s 99 counties. The number of dead deer in each county ranges from a low of 10 to a high of 138.
“2012 was the number one year for EHD-infected deer in Iowa and 2013 is the number two year all time,” said Litchfield, who noted that prior to the last two years, the last significant outbreak of EHD was in 1998 with 457 dead deer reported statewide. “Two years in a row is highly unusual,” he said.
Epizootic Hemorrhagic Disease is caused by a virus spread by biting insects called midges. Warm dry weather favors a buildup of the midge population and increases the likelihood of an outbreak. Once infected, the virus multiplies very quickly within a deer, causing high fever, breakdown of cell walls and dehydration. In later stages of the disease the animals will be lethargic, stumbling, sometimes drooling and unresponsive.
Death is caused by internal hemorrhaging and internal fluid buildup within one to four days after the fever begins.
Wildlife officials had expected that there would be more EHD deaths reported as hunters and landowners got into the field.
Litchfield said that outbreaks of EHD usually occur every 10 or 15 years when the weather conditions are conducive. EHD will infect both sexes and all ages of whitetail deer. A midge is like a gnat. When a midge carrying EHD bites a deer, the deer becomes infected. The disease cannot spread from deer to deer. Humans cannot get EHD from a midge or by any other means. Humans cannot get EHD from handling an EHD-infected deer carcass.
Litchfield said that EHD has been in the United States for many decades, especially in several southern states. The deer in the southern states have been exposed to the disease so much over the years that they have built up a tolerance to it and are now virtually immune.
Litchfield said that hunters or anyone else who finds a dead deer should report it to their local DNR warden. He said that if the carcass looks “new,” it would be especially important to report it because that deer most likely died from something other than EHD.
It is highly unlikely that the perfect conditions will exist in June, July and August of 2014 in order to produce another large outbreak of EHD, especially as far north as Clayton County.