Press Release

Epizootic hemorrhagic disease detected in Southwest Idaho

Editor's Note: This press release was updated on Sept. 17 after Fish and Game received confirmation that the sample taken from a white-tailed deer in the Garden Valley area was positive for EHD.

A sample collected from dead mule deer in Southwest Idaho has tested positive for epizootic hemorrhagic disease. The deer was recently discovered in the Treasure Valley within the Garden City limits, and Fish and Game wildlife staff confirmed that the deer was positive for EHD on Sept. 13.

Elsewhere in the Southwest Region, there have been five reports of dead white-tailed deer in the Garden Valley area since Sept. 8, and Fish and Game staff on Sept. 16 received confirmation that a sample taken from one of those deer carcasses was also positive for EHD.

The reported cases have been localized and have not affected large numbers of deer. Biologists in the Southwest Region will continue to monitor the situation closely, and are asking anyone who sees a sick or dead deer to contact the Southwest Regional office at 208-465-8465, or report sick or dead deer on our Wildlife Health reporting page. These reports play an important role in helping document the extent of the effects of EHD on deer populations.

What is EHD?

Hemorrhagic disease has been documented in most of Idaho and outbreaks occur sporadically, typically during hot, dry summers like this one. Hemhorrhagic disease primarily affects white-tailed deer, but the disease can also affect mule deer, pronghorn and bighorn sheep.

The disease is spread by the bites of a small gnat, which reproduce in warm, stagnant pools of water.  This summer’s hot, dry conditions proved to be ideal for the gnats to experience a population boom, creating the perfect storm of an abundance of gnats at water sources where deer congregated to stay hydrated.

Other EHD news in the state

Fish and Game biologists in the Clearwater Region have been closely monitoring large numbers of white-tailed deer deaths from hemorrhagic disease near Kamiah since early-August. You can learn more about that situation in the Aug. 31 update, which contains helpful FAQs on hemorrhagic disease.

Fish and Game announced last week that multiple samples collected from dead deer in the Panhandle have tested positive for epizootic hemorrhagic disease, and that they are continuing to monitor the situation. Read the press release.

For more information on epizootic hemorrhagic disease, click here, and check out the video below.


Q: What are clinical signs of EHD in deer?

A: Clinical signs include sluggishness, difficulty breathing and swelling of the head, neck and tongue. Ulcers or erosions of the tongue or gums may be present. Internal lesions include swelling and fluid accumulation in the lungs, ulcers in the abdomen and hemorrhages on the heart and intestines. Animals with chronic EHD can have abnormal hoof growth, hoof sloughing and sometimes are emaciated. Infected deer can also lose their appetite, become weak, can have bloody diarrhea, and show excessive salivation. They develop a rapid pulse and respiration rate along with fever, which is why they are frequently found lying in bodies of water to reduce their body temperature.

Q: Can EHD be spread to humans or pets?

A: Humans and domestic pets such as dogs and cats cannot be infected with EHD disease. White-tailed deer are particularly susceptible, but it can affect mule deer. Cattle and sheep can be exposed to the virus, but they rarely exhibit clinical signs to the varieties of EHD that typically affect wildlife.

Q: Is the meat of an EHD infected deer safe to eat?

A: Our veterinary staff recommends never eating an animal with a fever and a widespread systemic infection. Deer that survive an EHD infection are safe to eat. These animals may exhibit a dark, gritty liver. Our veterinary staff always recommends thoroughly cooking all game meat.

For more FAQs, click here.

white tailed deer carcass from epizootic hemorrhagic disease June 2017
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white tailed deer carcass from epizootic hemorrhagic disease June 2017