PIERRE, S.D.- A second case of a highly contagious, but rare horse disease has been confirmed in South Dakota, and officials in the region are urging horse owners to do what they can to help prevent the spread of the potentially fatal disease.
State Veterinarian Dustin Oedekoven said Friday, May 4, that the most recent case of equine herpesvirus myeloencephalopathy was confirmed on Monday and involved a horse that belonged to a member of the South Dakota State University rodeo team in Brookings.
The horse had just been at two rodeos over the weekend in Lincoln and Hastings, Neb., he said.
The other case, also involving a rodeo horse, was reported April 10 near Sioux Falls. Both horses were treated and able to recover.
However, in the North Dakota case reported last month, the horse had to be euthanized and was also tied to rodeos as it belonged to a member of a rodeo team in the southwest part of the state. Oedekoven also said they were previously aware of two cases in Wyoming near Gillette in recent months.
Oedekoven and Minnesota Board of Animal Health equine program manager Courtney Wheeler are urging horse owners to be vigilant, especially if they are traveling to rodeo and other public exhibition events.
In both South Dakota and Minnesota, the two said certificates of veterinary inspection and health are required for horses traveling out of state.
This verifies the horse has been examined by a veterinarian and is free from signs of communicable and contagious diseases.
Oedekoven said there is a vaccine for EHM, which has a neurological and often fatal effect to it, as well as for other forms of the disease. One of the related diseases found in younger animals is a respiratory form of the disease that can often be cured. Another form can affect mares and can cause abortions. Vaccines are also available for those forms of the disease.
EHM, however, is much more rare. For example, Oedekoven said the last case may have been as long ago as 2014. Wheeler said the last case in Minnesota that was reported was in 2015.
Wheeler, who is worried about Minnesota horses since the three cases reported in the Dakotas, said if a Minnesota horse is confirmed to be EHM positive or has been determined to be exposed to the disease, it must be quarantined. The board then works with herd veterinarians and horse owners to carry out testing and observation protocols defined in the control plan before the quarantines can be released.
Horse owners attending events need to adhere to rigorous and routine biosecurity practices to prevent the further spread of EHM and other contagious diseases, Wheeler and Oedekoven said.