The California Department of Food and Agriculture (CDFA) has reported that one additional horse that attended the event in Riverside County and had returned to his home premises in Sonoma County displaying fever only with no neurologic signs was confirmed positive for EHV-1.
The horse is currently isolated and under veterinary treatment at an offsite facility for an unrelated condition.
Three additional horses on the index event premise—one inside and two outside of the index quarantine barn—which were displaying fever only with no neurologic signs were confirmed positive for EHV-1.
To date, there have been three confirmed equine herpesvirus myeloencephalopathy (EHM) cases (EHV-1 infection with neurological signs) and 23 confirmed EHV-1-positive horses that were fever-only cases associated with this incident.
CDFA continues to be on site at the event premises and is actively monitoring the situation.
Information for this report was provided by the Equine Disease Communication Center.
