New cases reported; EHV quarantine to continue
February 16, 2023
Following the diagnosis of a fourth premises with Equine Herpes Virus 1 (EHV-1) in Flathead County, the Department of Livestock has quarantined an equine event/boarding facility and is extending the recommendation for limiting travel and cancelling events in the valley that bring horses from multiple sources together through Feb. 17.
Horses at three private premises and a single equine event/boarding facility have now been diagnosed with EHV-1, with exposed horses on these premises quarantined. In the latest case, the clinical animal was euthanized due to the severity of clinical signs and associated poor prognosis. The animal was boarded at a public facility, prompting the additional actions by the Department.
"We recognize the substantial disruption when an event facility is quarantined, however, previous measures have not stopped additional cases," said Montana State Veterinarian, Dr. Martin Zaluski.
EHV-1 is a potentially serious disease of horses that can cause respiratory or neurologic disease in affected animals. The neurologic form of disease, equine herpes myeloencephalopathy, is often fatal or leads to euthanasia. The most recent positive case brings the case count to 6 (4 confirmed and 2 suspected) on 4 separate premises. Five of the confirmed and suspected cases have been euthanized. Exposed horses from affected premises are subject to quarantine for 21 days beyond the last date of potential exposure.
Horse owners who have attended events in the Flathead Valley in recent weeks should monitor their animals for fever (temperature greater than 101.5 ̊ F) or development of any neurologic signs for two weeks after their last travel. Neurologic signs can include incoordination, difficulty walking, weakness, paralysis, inability to stand, poor tail tone, and difficulty urinating. Horses infected with EHV-1 may also have respiratory signs such as cough, nasal discharge, lethargy, and decreased appetite. Horse owners concerned about the health of their horses should contact their local veterinarian. Suspected cases of EHV-1/EHM should be reported to the Department immediately.
Montana Livestock Crimestoppers: 800-503-6084