The California Department of Food and Agriculture (CDFA) has confirmed that an additional exposed horse on the San Bernardino County premises with previous Neurologic Herpesvirus cases has been confirmed positive for neurologic herpesvirus. That brings the total to four neurologic horses—three of which have been euthanized—and five other horses which became febrile. All of the latter five were confirmed positive for EHV-1.
The most recent neurologic case was an 11-year-old Paint stallion that became febrile and showed neurologic signs.
The remaining horses on the property are alive and recovering, if they had been ill. CDFA is continuing to monitor the situation.
The outbreak started on October 29, when a 13-year-old Quarter Horse mare was euthanized due to neurologic equine herpesvirus (EHV-1). The diagnosis of equine herpesvirus myeloencephalopathy (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, that was exhibiting neurological signs was also confirmed positive for EHV-1.
Information for this report was provided by the Equine Disease Communication Center.