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.

BROOMFIELD, Colo. –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.

Equine Infectious Anemia (EIA)

On May 4, 2017, 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). There are now two additional cases of EIA at the same location, these horses belong to the same owner. All three horses have been euthanized. The Weld County facility is currently under a quarantine order that restricts movement of horses until further testing is completed by CDA.

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. EIA is not transmissible to people.

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.

Equine Herpesvirus Myeloencephalitis

The Colorado Department of Agriculture is investigating a confirmed case of Equine Herpesvirus Myeloencephalitis, which is a form of Equine Herpes Virus (EHV-1), within the state; a Mesa County premises has been placed under quarantine. The horse is quarantined after showing neurological clinical signs associated with the disease and subsequently testing positive for EHV-1. Currently the horse is under private veterinary care and seems to be making a good recovery. The horse had been to events over the previous two weeks, and all of those events have been notified. Event organizers are communicating with participants to monitor their horses for signs of the disease, especially for fever (temperature over 101.5 degrees F).

EHV-1 is not transmissible to people; it can be a serious disease of horses that can cause respiratory, neurologic disease and death. The most common way for EHV-1 to spread is by direct horse-to-horse contact. The virus can also spread through the air, and indirectly through contaminated equipment, clothing and hands. Proper biosecurity practices are vital to preventing the spread of this virus.

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 it is not a disease that the State Veterinarian’s Office will issue State quarantines for affected facilities or horses. While it is recommended for an infected barn to limit movement, restrictions with equine strangles are managed by the barn and the attending veterinarian.

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 the antibodies that they receive from the mare decline which is usually around four months of age but it can be very 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.