EHV-1: The Information You Need, and Where to Find It

With a new EHV-1 outbreak being reported in the Upper Midwest, Lindsey Kahn reminds us that when it comes to preventing the spread of disease, knowledge is power.

From Lindsey:

A recent outbreak of Equine Herpesvirus-1 (EHV-1) in eastern Minnesota has caused many upper Midwestern shows and events to be canceled for biosecurity reasons. The first cases were detected in horses that attended a barrel event in early March, with three EHV-1 positive horses euthanized thus far and three horses currently recovering. Stillwater Equine Veterinary Clinic is issuing up-to-date information regarding any current and new cases, and is providing helpful links to EHV-1 resources for owners’ peace of mind and to educate the public about this contagious virus. Fortunately, as of March 25th, there have been no new cases to report.

According to the Center for Equine Health at UC Davis, EHV-1 is a DNA virus that comes in two forms. One form causes respiratory and neurological symptoms in horses, such as nasal discharge, cough, weakness and uncoordination, and more serious neurological dysfunctions like a “coma-like state.” The other form causes abortion in pregnant mares.

According to Kate Samuels’ “EN Today: EHV-1 Precautions” on Eventing Nation,

• EHV-1 is spread by direct horse-to-horse contact, by contaminated hands, equipment and tack, and for a short time, through aerosolization of the virus within the environment of the stall and stable. If you’re in a barn with multiple horses, be smart and don’t share any tack or grooming supplies with your neighbors. If possible, prevent your horse from interacting with others.

• The virus can also be spread by coughing or sneezing over a distance of up to 35 feet. If you see a horse sneezing or coughing, take some precautions and disinfect yourself thoroughly.

• Good news: the virus is easily killed with disinfectant. If you feel the need, wear rubber gloves/booties around the barn and disinfect your stalls and trailers to help insure that the virus is kept at bay. Wash your hands in between handling different horses, and if you have to be in contact with a sick horse, change your clothing.

• If you think your horse is at risk, monitor their temperature, and record it 2x a day. The first sign of the virus is in increased temperature. Anything over 101 degrees, and you should notify your vet.

• If your horse develops fever, respiratory signs (including nasal discharge or cough) and neurological signs (incoordination, weakness, difficulty standing, lethargy, difficulty controlling urination or defecation), immediately notify your veterinarian and do not move other horses in the immediate area. At this point, supportive treatment is the only option and is tailored to the individual patient.Vets will usually use anti-inflammatory drugs, fluids and in extreme cases putting horses in slings to keep them upright. Horses that are able to stay standing have a good prognosis, but once they go down it is not a good sign.

The University of Minnesota Equine Center is webcasting an informational session on EHV-1 tonight, Wednesday March 26th at 7 PM CST. The presentation will not be recorded, so check out this link to view the informational session live: [U of M EHV-1 Webcast]

Here are some other informative links regarding the symptoms, management, prevention, and treatment of horses with EHV-1:

UC Davis Center for Equine Health – Equine Herpesvirus

University of Minnesota Equine Extension

University of Kentucky Gluck Equine Research Center

Please take the time to educate yourselves and your friends and to practice responsible horse management, no matter which health risk is circulating at the time. Understanding EHV-1, minimizing the risks of spreading it, and engaging in proper hygiene and biosecurity measures will help limit the spread of the disease.