media release

Colorado Department of Agriculture




September 18, 2012

Contact:    Christi Lightcap, (303) 239-4190,


Epizootic Hemorrhagic Disease Diagnosed in Colorado


LAKEWOOD, Colo. – Epizootic Hemorrhagic Disease (EHD) has been diagnosed in yak at two locations in Larimer County and one location in Alamosa County; these three cases have been confirmed by laboratory diagnostic tests at Colorado State University.  

There have been field reports of other yak in various Colorado locations that have shown similar clinical signs but those sick animals have not had laboratory tests performed to confirm the presence of the EHD virus. 


“We have not had confirmed positives of EHD in recent years but this is the time of year, in late summer and early fall, that we would expect to see cases,” said State Veterinarian Dr. Keith Roehr.


EHD is a viral disease that affects deer, cattle and, most recently, yak.  Signs of EHC includeThe signs that may be expressed with EHD are  fever, loss of appetite, weakness, respiratory distress, and swelling of the tongue, and erosive lesions in the mouth.  The disease cannot be transmitted by direct contact and is spread by insects, most commonly midges or gnats.


“Occurrence of the disease will diminish as hard frosts kill the virus and virus carrying insects.  Until then, it is important for producers to practice insect control to help prevent the spread of the disease,” said Roehr.

Occurrence of the disease will diminish as hard frosts kill the virus as well as the virus carrying insects.


Recently, cases in deer and cattle have been diagnosed in Nebraska and South Dakota. The deer population in Nebraska has seen a significant number of cases this year. Further investigation is ongoing to determine if the outbreak in Colorado may be tied to the Nebraska cases. those cases in Nebraska. 


“It is important that livestock producers and veterinarians are aware of the potential of EHD to affect their livestock,” said Dr. Roehr.


The EHD virus does not affect people. While there is no direct treatment for the EHD virus, supportive care is important to enable animals to recover from the disease. Insect control is an important tool to prevent disease.