Horse Illustrated Magazine

In August, 40 cases of Equine Infectious Anemia (EIA) were found at an Arkansas ranch. The remaining horses at the ranch are in quarantine.

EIA, also known as swamp fever, is a highly contagious disease that affects the immune system. It is most often spread by biting insects. Although not all infected horses will die of the disease, they will always be carriers and there is no cure and currently no approved vaccine in the United States. The test for EIA, commonly called a Coggins test for the vet who developed it, is required in many states. Because of the contagious nature of EIA, horses that test positive must be quarantined for life or euthanized.

In Arkansas, horses are required to have a Coggins test pulled every 12 months. The owner of the affected ranch hadn’t had the full herd tested in approximately five years. The horses had retired from competing and new horses rarely came to the farm, making for a fairly insular environment. However, because most of the horses had not been tested in years, it’s possible that the disease was incubating in unaffected carriers in the herd, according to Arkansas State Veterinarian George Pat Badley, DVM.

The most recent equine addition to the farm had arrived approximately six months ago. Veterinarians tested horses at the farm where that horse had previously lived and found no positive cases. Currently, they believe this outbreak is isolated.

All horse owners are encouraged to have their horses tested regularly. As part of standard biosecurity, farm owners should require any horse arriving on the property to show a recent, negative Coggins test.

Click here to read information about the outbreak from the Arkansas Livestock and Poultry Commission.