The Washington state veterinarian confirmed on Nov. 15 that two horses in Spokane County tested positive for equine influenza, and 40 other horses were exposed. The positive horses, a 7-year-old Thoroughbred gelding and a 5-year-old Warmblood mare that were both reported as undervaccinated, presented to veterinarians on Nov. 10 with clinical signs that included coughing, fever, and nasal discharge. They are reportedly recovering.

“The reporting vet tested two of her client animals but said she noticed other horses that were coughing, but were not her clients’,” said WSDA Regional Field Veterinarian Ben Smith, DVM. As a result, the reporting veterinarian advised the farm owner to enact a self-quarantine.

About Equine Influenza

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

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