In an effort to prevent confusion, the Colorado Department of Agriculture is providing an update on three separate equine health concerns currently affecting horses in Colorado. There are confirmed cases of Equine Infectious Anemia (EIA), Equine Herpesvirus Myeloencephalitis, and Strangles.
“The Colorado Department of Agriculture is working with the equine industry and veterinarians to contain the spread of these diseases. Owners should always practice proper disease prevention practices for their horses. Proper sanitation and biosecurity is often the first step in protecting your horse,” said State Veterinarian, Dr. Keith Roehr.
Equine Infectious Anemia (EIA). In May, the State Dept. Of Agriculture and Veterinarian’s Office, was notified by the US Dept. of Agriculture’s National Veterinary Services Laboratory (NVSL) that a Weld County horse tested positive for EIA. There are now two additional cases at the same location and the horses belong to the same owner. The horses have been euthanized. The facility is currently under a quarantine order.
Equine Infectious Anemia is a viral disease spread by bloodsucking insects, inappropriate use of needles, or other equipment. Infected horses may not appear to have any clinical signs of the disease, but it can cause high fever, weakness, weight loss, anemia, weak pulse and even death. There is no cure for the disease, so infected animals have to be quarantined for life or euthanized. EIA is not transmissible to people.
Equine Herpesvirus Myeloencephalitis. The State Department of Agriculture is investigating a confirmed case, which is a form of Equine Herpes Virus (EHV-1), in a Mesa County premises now under quarantine. Currently the horse is under private veterinary care and seems to be recovering. EHV-1 can be a serious disease of horses that can cause respiratory, neurologic disease and death. The most common way for it to spread is by direct horse-to-horse contact, but can also spread through the air, and indirectly through contaminated equipment, clothing and hands.
Clinical signs include fever, decreased coordination, nasal discharge, urine dribbling, loss of tail tone, hind limb weakness, leaning against a wall or fence to maintain balance, lethargy, and the inability to rise. While there is no cure, the clinical signs of the disease may be treatable.
Strangles. Recently, the State Veterinarian’s office has received a high volume of calls with questions regarding equine strangles. In Colorado, equine strangles is not a reportable disease, and therefore the State Veterinarian’s Office does not issue quarantines for.
Strangles is a contagious disease of horses of all ages but it is more commonly seen in young horses, usually less than two years of age. Foals are usually not susceptible until usually around four months of age but it is variable. Commonly, once a horse has gone through the infection, they become immune to developing clinical signs again or the disease is not as severe the next time it develops in their system.
Using common sources of water, feed bunks, and housing allows transmission of the bacteria from horse to horse. Horses that are spread out in pastures or large exercise areas in which they can move and graze will not share the infection as readily.
In instances where accredited veterinarians have questions, we are happy to assist in developing plans for biosecurity and herd management to attempt to minimize the impact of an outbreak.