Equine herpesvirus detected in horse in Olmsted County
The 20-year-old Warmblood mare had onset of clinical signs on March 21 that included hind limb ataxia, flaccid tail and urinary bladder atony. She was confirmed positive for equine herpesvirus (EHV-1) on March 25.
ROCHESTER, Minn. — The state of Minnesota has confirmed a case of neurologic equine herpesvirus at a boarding facility in Olmsted County. There is an official quarantine at the facility where 25 other horses were exposed. Neurologic herpesvirus is also known as equine herpesvirus myeloencephalopathy (EHM).
The 20-year-old Warmblood mare had onset of clinical signs on March 21 that included hind limb ataxia, flaccid tail and urinary bladder atony. She was confirmed positive for equine herpesvirus (EHV-1) on March 25. The vaccinated mare was euthanized. Officials enacted a quarantine for 25 more horses that were potentially exposed.
On March 25, the Minnesota Board of Animal Health released the following notification:
In accordance with the Board’s Equine Herpesvirus Myeloencephalopathy (EHM) Control Plan, “Following the declaration of quarantine of an EHM positive horse, the Board shall in a timely manner post on its web site the name and location of the facility where the EHM positive horse is identified and any other locations where the EHM positive horse was kept in the 72 hours prior to the onset of neurological symptoms.”
The facility address is:
Priestfield West Stables
6708 20th St SW
Byron, MN, 55920
According to the Minnesota Board of Animal Health, Equine herpesvirus (EHV) is a contagious virus that can cause four clinical presentations including: neurological disease, respiratory disease, neonatal death and abortion. Equine herpesvirus myeloencephalopathy (EHM) is the neurologic disease that develops as a result of EHV infection. The virus has been associated with neurologic cases in llamas and alpacas, but has no effect on people or other types of livestock.
The virus is usually spread in nasal secretions between horses that are in close contact with each other or that share water or feed pails. The virus does not typically survive very long in the environment or on people or equipment. It is killed readily by most disinfectants, ultraviolet light and by drying. Infected horses are generally treated with supportive care. Anti-inflammatory drugs and antiviral medications are often used for those that develop the neurologic form of the disease.
EHM positive horses and EHM exposed horses must be quarantined as outlined in the Board of Animal Health EHM control plan. Board staff members will then work with herd veterinarians and horse owners to carry out the testing and observation protocols defined in the control plan before the quarantines can be released.