11/23/2025
Equine Disease Communication Center
As we continue to monitor the current outbreak of the neurologic form of equine herpesvirus infection (equine herpesvirus myeloencephalopathy, EHM), let's take this opportunity to discuss once more the importance of biosecurity measures to stop disease spread. We recommend the following biosecurity precautions for horse owners, particularly if their horses have recently traveled to horse shows or were exposed to horses that have traveled:
1) Monitor horses for clinical signs (including fever, discharge from the nostrils, toe-dragging or a lack of balance) and take the temperature twice daily. Temperature greater than 101.5 F is considered a fever.
2) Immediately isolate any horse(s) showing clinical signs. Equine herpesvirus is an aerosolized virus and is spread through shared airspace, direct contact, and contaminated caretakers or equipment. A good isolation area is a separate barn or shelter that does not share airspace with healthy horses.
3) Implement movement restrictions until the situation is evaluated.
4) Contact your veterinarian to evaluate your horse and to propose a comprehensive biosecurity protocol.
5) Increase biosecurity measures that include extensive cleaning and disinfection of surfaces and equipment that come in contact with affected horses: wash or sanitize your hands between interacting with horses; take time while filling water buckets and feed tubs, do not cross contaminate; minimize the use of shared equipment and tack.
6) Make sure your horse is up to date on vaccinations.
7) Establish communication with all parties involved (owners, boarders, trainers, etc.).
More resources and information regarding biosecurity are available on the Equine Disease Communication Center's website at https://equinediseasecc.org/biosecurity
To learn more Equine Herpesvirus (EHV), visit: https://www.equinediseasecc.org/equine-herpesvirus
For outbreak updates, check the post here: https://equinediseasecc.org/news/article/Equine-Herpesvirus-Myeloencephalopathy-(EHM)-Outbreak
