Your Guide to Equine Health Care

Update on Equine Influenza Outbreak in Mustang Herd

One more horse has died in an ongoing EI outbreak in Colorado.

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Update on Equine Influenza Outbreak in Mustang Herd
One more horse has died in an ongoing equine influenza outbreak in Colorado. | Wikimedia Commons

The Bureau of Land Management (BLM) provided an update on May 28 to the ongoing equine influenza outbreak in Fremont County, Colorado. To date, 144 Mustangs at the Cañon City Wild Horse and Burro Facility have died from the disease.

The outbreak began on April 23, when nine horses in four pens were found dead. The horses had been gathered from The West Douglas Herd Area in July and August 2021. Two dozen more horses promptly started showing clinical signs and died or were euthanized. A wildfire occurring shortly before the horses were gathered might be a contributing factor, because smoke can stress horses’ respiratory systems.

The BLM continues to investigate the outbreak and monitor the situation.

EDCC Health Watch is an Equine Network marketing program that utilizes information from the Equine Disease Communication Center (EDCC) to create and disseminate verified equine disease reports. The EDCC is an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.

About Equine Influenza

Equine influenza is a highly contagious respiratory disease that infects horses, ponies, and other equids, such as donkeys, mules, and zebras. The virus that causes it is spread via saliva and respiratory secretions from infected horses. Horses are commonly exposed via horse-to-horse contact; aerosol transmission from coughing and sneezing; and contact with humans’ contaminated hands, shoes, or clothes or contaminated tack, buckets, or other equipment.

Clinical signs of equine influenza infection can include a high fever (up to 106°F); a dry, hacking cough; depression; weakness; anorexia; serous (watery) nasal discharge; and slightly enlarged lymph nodes. Consider monitoring your horse’s health at shows by taking his temperature daily, which can help you pick up on signs of infection early and take appropriate measures to reduce disease spread.

Vaccination is an important and inexpensive way to protect your horse. US Equestrian requires proof that horses have had an equine influenza vaccination within the six months prior to attending organization-sanctioned competitions or events. Your veterinarian can help you determine what other vaccines your horse might benefit from.

In addition to vaccinating, following strict biosecurity protocols can help reduce your horse’s chance of infection and disease. Such measures include quarantining new equine arrivals at barns, disinfecting buckets and equipment, and preventing nose-to-nose contact between horses.

Brought to you by Boehringer Ingelheim, The Art of the Horse


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