New Mexico EHV-1: Additional Cases Confirmed

New Mexico EHV-1: Additional Cases Confirmed

In many horses, fever is the only sign of EHV-1 infection, which can go undetected.

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

The New Mexico Livestock Board (NMLB) reported Jan. 26 that additional horses residing at a racetrack in New Mexico have tested positive for equine herpesvirus-1 (EHV-1), bringing the total case count to 18.

“These horses are from 13 different barns within Sunland Park racetrack; at present, horses in surrounding areas have tested negative,” the report stated. “Of these 18, one horse has been euthanized for neurologic symptoms.”

No movement of horses is being allowed in or out of Sunland Park. Officials with the NMLB, New Mexico Racing Commission, and Sunland Park will continue to work together to resolve the issue, the statement said.

Herpesvirus is highly contagious among horses and can cause a variety of ailments in equids, including rhinopneumonitis (a respiratory disease usually found in young horses), abortion in broodmares, and myeloencephalopathy (the neurologic form). In many horses, fever is the only sign of EHV-1 infection, which can go undetected.

In addition to fever, other common signs of EHV-1 infection in young horses include cough, decreased appetite, depression, and a nasal discharge. Pregnant mares typically show no signs of infection before they abort, and abortions usually occur late in gestation (around eight months), but can be earlier. Abortions can occur anywhere from two weeks to several months following infection with EHV-1.

Horses with the neurologic form usually have a fever at the onset of the disease and might show signs of a respiratory infection. A few days later, neurologic signs such as ataxia (incoordination), weakness or paralysis of the fore- and hind limbs, urine retention and dribbling, loss of tail tone, and recumbency (inability to rise) develop.

Editor's Note: This article was update to include the most recently released case totals.

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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