Additional EHV-1 Cases Confirmed in California

Additional EHV-1 Cases Confirmed in California

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

Two additional California horses have tested positive for neurologic equine herpesvirus-1 (EHV-1) after an Oldenburg mare was diagnosed with the disease on Aug. 23. The most recent cases were confirmed on Aug. 24, according to a statement from the California Department of Food and Agriculture (CDFA).

The only clinical sign exhibited by the most recently confirmed cases was a fever, the statement noted.

"The affected premises is under quarantine and the 13 other horses currently on the property are being monitored," the release said. "Current epidemiologic investigation findings indicate minimal risk of disease spread from this closed premises."

Further, the CDFA indicated that this case has "no direct link" to the widespread EHV-1 outbreak that took place in the western United States and Canada in May and June of this year.

Although it's not transmissible to humans, EHV-1 is highly contagious among horses and camelids, and it is generally passed from horse to horse via aerosol transmission (when affected animals sneeze/cough) and contact with nasal secretions. The disease can cause a variety of ailments in equines, 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 the hind limbs, and incontinence.

The CDFA relayed Monday (Aug. 29) that no further cases of EHV-1 had been confirmed as of that time.

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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