3 California Horses EHM Positive in Inyo County


December 8, 2016

California officials report two more febrile horses in Inyo County have been confirmed positive for the neurotrophic EHV-1 strain. Neither horse is exhibiting neurologic symptoms.

Last week a horse at the same farm tested positive for what officials described as a different strain of EHV-1 that causes EHM, the neuropathic form of the virus.

The California Department of Food and Agriculture (CDFA) says the 20-year-old Quarter Horse gelding presented with mild neurologic symptoms. The gelding is part of a wintering pack string of 28 horses and four mules on an isolated, high desert ranch. The state quarantined the herd.

CDFA has launched an investigation.

The agency states that strain is biologically distinct from the strain identified in the cases in LA County. W. Kent Fowler, DVM, Animal Health Branch Chief for CDFA says, “both strains can cause neurologic symptoms in the horse, although the neuropathic strain is more likely to cause neurologic symptoms.”

Los Angeles Equestrian Center’s EHV outbreak involves 13 cases. The last confirmed case was on November 23.

One horse remains in isolation at the boarding stable and equestrian venue.