This week, the Colorado Department of Agriculture, State Veterinarian’s Office, was notified by the US Department of Agriculture’s National Veterinary Services Laboratory (NVSL) that a Weld County horse tested positive for Equine Infectious Anemia (EIA). The Weld County facility is currently under a quarantine order that restricts movement of horses until further testing is completed by the Colorado Department of Agriculture (CDA).

“Because the disease is not curable, the affected horse has been euthanized. The remaining horses on the facility will be observed and retested in 60 days.  The disease is most commonly spread by biting flies and it is very early in Colorado’s fly season; therefore, the risk of disease transmission to other horses at this time is relatively low,” said State Veterinarian, Dr. Keith Roehr.

FAQs about Equine Infectious Anemia

What is Equine Infectious Anemia?

Equine Infectious Anemia is a viral disease spread by bloodsucking insects, inappropriate use of needles, or other equipment used between susceptible equine animals such as horses, mules and donkeys. Horses may not appear to have any symptoms of the disease, although it also can cause high fever, weakness, weight loss, an enlarged spleen, anemia, weak pulse and even death.

How is it spread?

It is spread most commonly through blood by biting flies such as horse flies and deer flies.

What happens to an infected horse?

There is no cure for the disease, so infected animals have to be quarantined for life or euthanized.

Is there a danger to people?

No. The disease can only be spread to horses, mules and donkeys.

Is the disease common?

No. There has only been a small number of cases in the United States, although the disease exists in other parts of the world. A map of cases from the year 2015 is available at https://www.aphis.usda.gov/aphis/ourfocus/animalhealth/animal-disease-information/horse-disease-information/equine-infectious-anemia/ct_eia_distribution_maps.

How is the disease controlled?

Equine Infectious Anemia is a disease for which horses must be tested annually before they can be transported across state lines. The test for EIA is commonly called a Coggins Test. 

More facts on EIA: http://www.cfsph.iastate.edu/Factsheets/pdfs/equine_infectious_anemia.pdf