MISSOULA, Mont. — Wildlife authorities in eastern Montana and northern Idaho are alerting the public after recent cases of epizootic hemorrhagic disease (EHD) and blue tongue virus (BTV) in deer and antelope.
Eastern Montana:
Wildlife managers in Region 7 report suspected cases of EHD and BTV in deer and antelope along the Yellowstone River and in nearby prairies. Lab testing has not yet confirmed the cases.
Both viruses are spread by tiny flies called midges and tend to show up during warm, dry conditions. Officials say infected animals often appear weak, disoriented, and are frequently found near water. Symptoms can include swelling of the head and mouth, drooling, and in some cases, a blue tongue. Deer and antelope typically die within 8 to 36 hours of showing symptoms.
EHD and BTV are not a risk to humans, but FWP advises hunters not to eat meat from sick animals. Deer densities may be lower than normal in areas hit hardest by the disease.
Anyone who finds sick or dead deer or antelope in the region is asked to report it to wildlife manager Brett Dorak at brett.dorak@mt.gov or (406) 234-0921.
Northern Idaho
In Idaho, lab tests confirmed EHD in deer from the Clearwater Region and both EHD and BTV in deer from the Panhandle Region.
EHD and BTV outbreaks happen periodically in the Clearwater and Panhandle regions, often during summers like this one. Because deer in northern areas have little natural immunity, outbreaks can hit hard and cause localized die-offs.
So far, fewer than 200 reports have come in from the Panhandle and fewer than 600 from the Clearwater. Fish and Game says the outbreaks will likely continue until cooler, wetter weather or a hard frost kills off the midges.
FAQ from Idaho Fish and Game:
Q: What’s the difference between hemorrhagic disease and CWD?
A: Both diseases are distinctly different from and unrelated to chronic wasting disease. Chronic wasting disease is a fatal and contagious disease that affects the nervous systems of deer, elk, moose and reindeer. Its effect on populations is long-term and chronic. Conversely, hemorrhagic disease outbreaks can be explosive and severe, but they are often localized and short-lived.
Q: What are clinical signs of EHD and BTV in deer?
A: Signs may include:
Labored or difficulty breathingSwelling of the head, neck, or tongueFluid in the lungs and internal hemorrhagesAbnormal hoof growth or hoof sloughing (in chronic cases)Weakness, loss of appetite, bloody diarrhea, and excessive salivationFever— which is why deer are often found lying in or near water to cool down
Q: Can EHD and BTV be spread to humans or pets?
A: Humans and domestic pets such as dogs and cats cannot be infected with EHD or BTV. White-tailed deer are particularly susceptible, but it can affect mule deer and elk. However, elk are less likely to develop severe forms of these diseases. Cattle and sheep can be exposed to both viruses, but they rarely exhibit clinical signs to EHD but are more susceptible to BTV.
Q: Is the meat of an EHD- or BTV-infected deer safe to eat?
A: Fish and Game veterinary staff do not recommend eating meat from deer found dead from EHD or BTV due to the possibility of secondary bacterial infections. Deer that recover from and survive an EHD or BTV infection are safe to eat.
How you can help
Please report sick or dead deer online via the Wildlife Health Reporting page. Public reports are vital in tracking the impact of hemorrhagic diseases on deer populations.
For more information, contact the Idaho Fish and Game Panhandle (208) 769-1414 or Clearwater (208) 799-5010 regional offices.