New EHV-1 Case in Wisconsin

New EHV-1 Case in Wisconsin

Myeloencephalopathy is characterized by fever, ataxia (incoordination), weakness or paralysis of limbs, and incontinence.

Photo: Stephanie L. Church, Editor-in-Chief

The Wisconsin Department of Agriculture, Trade, and Consumer Protection has confirmed that a St. Croix County horse tested positive for equine herpesvirus-1 (EHV-1) yesterday (April 8).

A statement on the department's website indicated that the horse tested positive for the non-neuropathic strain of the virus on virus isolation and blood, and the horse's condition is improving.

"This is only the second horse in Wisconsin to have tested positive for the virus," the statement read. "A third horse was euthanized and later tested negative for the virus."

In an April 8 Facebook post, Anoka Equine Veterinary Services, in Elk River, Minn., said they are awaiting test results on an Isanti County, Minn., horse who "was neurologic and unable to urinate. This horse is at a large facility and that facility has been closed, no new horses have entered the property. This means (the virus) was (likely) brought in by a human in some way … on equipment, shoes, hands, tack, etc. This is an entirely new case and does have a high probability of having positive results. Test results are expected back this coming Friday or Monday."

The Wisconsin state veterinarian recommends that owners keep horses with a fever and clinical signs of contagious respiratory infection at home and not take them to shows, competitions, clinics, or public trail rides, the Wisconsin statement noted.

"Horse owners should also be aware that transportation of horses to competitions, shows, and clinics may increase the risk of exposure to infectious organisms," the statement continued. "Although humans can’t be infected by EHV-1, they can aid in spreading it to their horses. Therefore, owners of affected horses should wash and disinfect their hands and change their clothes before coming into contact with healthy horses to prevent the potential spread of these infectious organisms."

Health Alert: Equine Herpesvirus

EHV-1 is highly contagious among horses and can cause a variety of ailments, including rhinopneumonitis (a respiratory disease usually found in young horses), abortion in broodmares, and myeloencephalopathy (EHM, the neurologic form). Myeloencephalopathy is characterized by fever, ataxia (incoordination), weakness or paralysis of limbs, and incontinence. will provide updates as additional information becomes available.

About the Author

Erica Larson, News Editor

Erica Larson, news editor, holds a degree in journalism with an external specialty in equine science from Michigan State University in East Lansing. A Massachusetts native, she grew up in the saddle and has dabbled in a variety of disciplines including foxhunting, saddle seat, and mounted games. Currently, Erica competes in eventing with her OTTB, Dorado.

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