On April 26, 2018, the California Department of Food and Agriculture confirmed equine herpesvirus type 1 (EHV-1) in two horses that had fevers and are from the previously quarantined barn at the Orange County Facility.
The first positive horse displayed a fever on April 23 and was placed in onsite isolation stabling. The second positive horse that initially tested negative over the weekend was moved off site for isolation and quarantine.
Enhanced biosecurity measures and twice daily temperature recording for all exposed horses in the quarantine barn continues.
To date, there have been seven confirmed febrile cases of EHV-1 and the one index case of equine herpesvirus myeloencephalopathy (EHM, or neurologic herpesvirus). Release of positive horses from quarantine isolation requires two negative tests seven days apart.
CDFA staff continues onsite monitoring of the situation.
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