Published January 27, 2013, 05:00 AM

TALKIN WITH DOKKEN: Epizootic hemorrhagic disease in deer

Brad Dokken answers the question: "What is Epizzotic hemorrhagic disease and how is it spread?

By: Brad Dokken, Grand Forks Herald

Q. A friend from southern Colorado shot a mule deer in November that was still in velvet. When he spoke with a conservation officer from the Division of Wildlife, he was told the deer had epizootic hemorrhagic disease and that the disease was becoming more common. What is this disease, how is it spread and have there been any cases reported here in North Dakota?

A. EHD is a naturally occurring virus that is spread by a biting midge. It is almost always fatal to infected whitetails, while mule deer usually don’t die from the disease.

And yes, there have been EHD outbreaks in North Dakota, most recently in the fall of 2011 in the southwest part of the state. The Game and Fish Department at the time called the losses “moderate to significant” and went so far as to offer refunds on whitetail tags in 10 southwest hunting units.

Based on reporting I did at the time, more than 13,000 hunters were eligible for refunds in the EHD-affected area but only about 800 actually turned in their tags to get their money back.

Traditionally, EHD outbreaks are most severe when high whitetail numbers combine with hot, humid weather late in the summer and early in the fall, creating ideal breeding conditions for the disease-transmitting midge.

EHD causes dehydration and a high body temperature, causing deer to seek water before they die. That explains why so many of the deer that died in 2011 were found along streams and creeks in the southwest part of the state.

According to a story I found in the Herald archives from 2003, other symptoms of EHD can include respiratory distress; swelling of the head, neck and tongue; lesions on the tongue and roof of the mouth; indifference to humans; and hemorrhaging from body orifices in later stations.

While fatal to whitetails, EHD is not dangerous to humans, and the first hard freeze typically kills the midge that carries and transfers the virus, in turning slowing or halting the spread of the disease. I don’t recall hearing of any significant EHD-related deaths this past fall in North Dakota.