A different strain of Equine Herpes Virus (EHV-1) causing Equine Herpes Myeloencephalopathy (EHM) has been confirmed in one horse with mild neurologic symptoms in Inyo County, CA, according to the California Department of Food and Agriculture (CFDA).
This is the neurologic strain, which is biologically distinct from the non-neurologic strain identified in all the LA County confirmed cases. The affected horse, a 20 year-old quarter horse gelding, is part of a wintering pack string of twenty-eight (28) horses and four (4) mules on an isolated, high desert ranch. These horses/mules have been placed under quarantine with no movement allowed in order to limit disease transmission. This disease outbreak is under investigation by CDFA staff onsite.
Los Angeles Equestrian Center (LAEC) outbreak has had a total of thirteen (13) EHV-1 confirmed cases, all of those caused by the non-neuropathogenic strain EHV-1 virus. There has been no new febrile horses since November 23rd and only one positive horse remains in isolation.