Two horses are in stable condition while being treated for neurologic equine herpesvirus-1 (EHV-1) at the University of Minnesota (UM) Large Animal Hospital, according to the treating clinician. Both animals–who reside at the same Wright County, Minn., farm–have tested positive for the virus since being admitted to the clinic this week. A third horse (the index case) from the same premises was euthanized after showing signs of disease.

Treating clinician Anna Firshman, BVSc, PhD, CERP, Dipl. ACVIM, ACVSMR, assistant clinical professor of Large Animal Medicine at the UM Veterinary Medical Center, told TheHorse.com that one horse began showing signs of neurologic disease suddenly on Nov. 10; the animal’s condition deteriorated rapidly, she said, and the decision was made to euthanize him.

Shortly thereafter, a second horse began to show clinical signs associated with EHV-1 and was admitted to the UM Large Animal Hospital on Nov. 11, Firshman said. Diagnostic tests soon confirmed EHV-1. The final horse began showing clinical signs not long after and was admitted to the hospital on Nov. 14, she relayed.

"A rapid genetic test was used to test for EHV-1," she said. "Results are already back and are positive for the virus