Hemorrhagic Disease Outbreak Hits Montana Deer And Antelope

Hunting season is underway, and if you’re out and about along the Yellowstone, Big Horn, or Clarks Fork River corridors this fall, you might spot a deer that looks like it’s been possessed by a low-budget zombie virus.

Unfortunately, the ugly-sounding wildlife diseases that made headlines in southeast Montana last year are back.

Montana Fish, Wildlife & Parks Region 5 reports dead and dying deer and antelope throughout south-central Montana in 2026, particularly along rivers. Testing of several carcasses confirmed hemorrhagic diseases, including epizootic hemorrhagic disease (EHD) and blue tongue (BT).

Neither disease is new, but both sound like something out of a Stephen King novel.

Tiny Bugs, Big Problems for Montana Wildlife

EHD and blue tongue are similar viral diseases spread by tiny biting flies called midges, sometimes known as “no-see-ums.” These pesky little bugs are especially active during warmer weather.

When infected midges bite deer or antelope, the animals can develop fever and severe dehydration. Affected wildlife may appear weak, lethargic, or disoriented, and some develop swollen heads or tongues that turn bluish in color.

Death can occur quickly, and sick or dead animals are often found near rivers and other water sources as they struggle with dehydration.

Is It Safe to Eat Deer Meat?

Here’s some reassuring news for hunters: FWP says these hemorrhagic diseases pose no risk to humans.

Meat from animals that appear healthy at the time of harvest is safe to eat when properly cooked. However, hunters should avoid harvesting or consuming animals that appear sick.

When Will the Outbreak End?

There is some good news. EHD and blue tongue outbreaks typically subside when hard frosts and colder weather reduce midge activity. FWP expects disease-related wildlife deaths to begin tapering off in the coming weeks as temperatures drop.

Agency staff continue monitoring the situation. If you find dead deer or antelope along waterways in Yellowstone or Big Horn counties, FWP says there is no need to report additional suspected cases.

Suspected cases in other Montana counties can be reported to Montana Fish, Wildlife & Parks at 406-247-2940. Learn more about the diseases HERE.