Horses in Santa Fe County are among those potentially exposed to a serious outbreak of equine herpes myeloencephalopathy, a neurologic disease that has already caused multiple horse deaths in other states, New Mexico livestock officials said Friday.
The New Mexico Livestock Board Office of the State Veterinarian identified Santa Fe County as one of seven counties in the state with horses that may have been exposed to the virus at recent rodeo events in Texas and Oklahoma.
The Texas Animal Health Commission and Oklahoma Department of Agriculture, Food, and Forestry confirmed cases of EHM, which is caused by equine herpes virus-1, on Tuesday. Affected horses attended the WPRA World Finals and Elite Barrel Race event in Waco, Texas, from Nov. 5-9, and the Barrel Futurities of America event in Guthrie, Oklahoma, on Nov. 17-18.
Other New Mexico counties with potential exposure include Dona Ana, Eddy, De Baca, Roosevelt, Otero and Chaves.
State veterinary officials are recommending that equine events be canceled or postponed until the extent of the outbreak is determined. Corrales canceled its popular Christmas horse parade Friday because of the outbreak.
“Presentation of EHV-1 in these horses has been acute with rapid progression and high clinical severity,” the livestock board stated. “A concerning number of mortalities in horses suspected of having EHM have been reported in other states.”
Horse owners whose animals attended the events are urged to isolate those horses for at least two weeks and monitor their temperatures twice daily for at least 14 days after the last known exposure. Fever greater than 101.5 degrees Fahrenheit is often the first indicator of infection.
Clinical signs of EHM include lethargy, nasal discharge, swelling of the legs, lack of coordination, hindquarter weakness and leaning against surfaces to maintain balance. Pregnant mares may abort.
Veterinarians should be contacted immediately if a fever above 102.5 degrees or other symptoms develop.
To prevent spread, officials recommend washing hands before and after working with horses, disinfecting clothing and footwear, and avoiding visits to other barns or facilities with horses.