The California Department of Food and Agriculture confirmed that a third horse on a premises in San Bernardino County has been euthanized due to equine herpesvirus myeloencephalopathy (EHM).
On October 29, a 13-year-old Quarter Horse mare was euthanized due to neurologic equine herpesvirus (EHV-1). The diagnosis of EHM was confirmed on November 5. Then on or about November 15, a 22-year-old Paint gelding was euthanized due to severe neurologic problems confirmed to be caused by neurologic herpesvirus.
One additional exposed horse on this premises, a 24-year-old Quarter Horse mare, is exhibiting neurological signs has been confirmed positive for EHV-1. Two additional febrile horses, a 22-year-old Paint mare and an 11-year-old Paint mare, also have been confirmed positive for EHV-1. There are another 13 horses on the premises that have been exposed but are not showing any fever or clinical signs.
The California Department of Food and Agriculture is onsite to observe biosecurity protocols and isolation of positive horses.