New EHV-1 Cases Confirmed in Minnesota

New EHV-1 Cases Confirmed in Minnesota

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

Photo: Anne M. Eberhardt/The Horse

A horse exhibiting neurologic signs at a Wright County, Minn., farm has tested positive for equine herpesvirus-1 (EHV-1), and several other horses residing at that farm were found to be shedding the virus, according to a statement from Anoka Equine Veterinary Services, in Elk River, Minn.

The horse's neurologic signs were first detected on March 29, and the clinic received the positive test result today (April 3), Anoka Equine announced on their Facebook page.

"All horses on this farm were tested to screen them for EHV-1," the April 3 statement read. "Of those tested, additional horses came back positive for shedding the virus, but they are not showing neurologic signs at this time." Horses in this situation are often referred to as "subclinical shedders," or horses that appear healthy on the outside but are experiencing active infection, with the potential of shedding—and spreading—the virus.

The clinic said those horses will be retested in three weeks to determine their shedding status.

"This facility is taking this very seriously; they are in tight lockdown," the statement read. "They have a very good quarantine protocol in place."

In an April 3 statement, the Minnesota Board of Animal Health said a total of "seven Minnesota horses with neurologic signs have tested positive for EHV-1 infection (non-neuropathogenic strain)." They also urged owners to "continue consulting their veterinarians on ways to protect their animals."

Health Alert: Equine Herpesvirus

Highly contagious among horses, EHV-1 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), limb weakness or paralysis, and incontinence. will continue to 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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