An Oregon horse has tested positive for the neurological form of the equine herpes virus (EHV-1), according to the state’s agriculture department. The horse from Marion County began showing acute neurological signs on Tuesday.
The infected horse was referred to the Oregon State University’s College of Veterinary Medicine’s Large Animal Hospital. A positive EHV-1 diagnosis was confirmed on Wednesday.
The index stable that holds 20 horses is under a mandatory quarantine. The Oregon Department of Agriculture reports there is no indication that the virus has spread to other horses beyond those being quarantined.
A preliminary epidemiological investigation is underway. To date, the investigation shows horses from the affected property attended a horse event held at the Linn County Fairgrounds, in Albany, on April 16 thru 19. Some of the horses were also at the Trail Clinic at the Oregon Horse Center, in Eugene, on April 23 to April 26.
“The detection of neurologic EHV-1 is taken very seriously, and we are doing our best to notify equine veterinarians and horse owners,” said State Veterinarian Dr. Brad LeaMaster. “We have had occurrences of the disease in Oregon in the past. I appreciate everyone’s cooperation in dealing with the disease investigation and control process.”
EHV-1 may lie dormant for long periods of time and then re-activate during a period of stress, which can result in clinical disease.
Symptoms may include fever, decreased coordination, nasal discharge, urine dribbling, loss of tail tone, hind limb weakness, leaning against a wall or fence to maintain balance, lethargy, and the inability to rise. While there is no cure, the symptoms of the disease may be treatable.
Veterinarians recommend that horse owners practice bio-security to protect their horses from being exposed to the virus since it is highly contagious and spread through direct horse-to-horse contact. It can also be spread through contaminated clothes, equipment, and hands.