The deaths of eleven wild horses in the last two weeks have been linked to an outbreak of equine distemper, commonly known as "strangles", at the BLM’s Salt Lake Regional Wild Horse & Burro Facility in Herriman, Utah. A necropsy or postmortem exam is being done on individual animals. Bacterial cultures are also being collected to isolate the specific Streptococcus bacteria infecting the horses. Having this information will help determine the best available treatment and allow horses to be treated with the most effective antibiotics.
Equine distemper is a common upper respiratory infection that occurs in horse populations, especially when confined in holding facilities. It is highly contagious, causing a lack of appetite, fever, listlessness and a distinct swelling of the lymph nodes in the throat area. Often signs include pus-filled lymph nodes, nasal discharge, breathing difficulty, and cold-like symptoms. When the immune system is weak, the bacteria can spread throughout the horse’s entire body creating a systemic infection. Once the disease has gone systemic, it is generally fatal.
The primary groups of horses affected by the bacterial infection are younger animals with weakened or immature immune systems. BLM personnel are working closely with the facility contract veterinarian to ensure the best care possible for those animals impacted by the infection. All animals at the facility are under a BLM-imposed quarantine and will not be shipped out until several weeks after any clinical signs are documented. BLM is also working closely with the Utah State Veterinarian and following his recommendations to ensure any further spread or outbreak of the disease is contained on-site.
The BLM has warned the public that due to the severity and contagious nature of the equine distemper occurring at the facility, public access may be limited at times while veterinary care and sanitation measures are being undertaken.