On April 29, 2018, the California Department of Food and Agriculture (CDFA) confirmed a new case of equine herpesvirus myeloencephalopathy (EHM). A 9-year-old mare from the quarantined barn at the Orange County facility was displaying neurological signs and has tested positive for equine herpesvirus Type 1 (EHV-1). Based on clinical signs and the detection of the EHV-1 virus, the horse has been classified as a case of EHM.
This mare has been placed in onsite isolation stabling.
To date, there have been seven confirmed febrile cases of EHV-1 (horses with fever, but no neurologic signs) and three confirmed cases of EHM. CDFA continues onsite monitoring of the situation.