FEBRUARY 23 UPDATE: Four additional horses on the event premises, one within the index quarantine barn and three housed outside of the index quarantine barn, displaying fever only with no neurologic signs, were confirmed positive for EHV-1. The positive horses have been placed in isolation and all horses in the exposure cohorts are isolated and under quarantine. To date, there have been three confirmed EHM cases (EHV-1 infection with neurological signs) and nine confirmed EHV-1 fever-only cases for this incident. CDFA continues to be on site at the premises and is actively monitoring the situation.
The California Department of Food and Agriculture (CDFA) confirmed three cases of EHV-1 (equine herpesvirus type 1) at a show grounds in Riverside County, with one horse showing neurologic signs. Forty-five other horses were exposed.
A 12-year-old Zangersheide gelding displaying neurological signs on February 10 was confirmed positive for neurologic equine herpesvirus (also known as equine herpesvirus myeloencephalopathy or EHM) secondary to equine herpesvirus type 1 (EHV-1 non-neuropathogenic strain) on February 11. The gelding was attending an equestrian event in Riverside County and has been isolated at the event premises.
Two additional horses displaying fever only that were housed in the same barn on the premises have also been confirmed positive for EHV-1 and isolated.
The three affected horses and an additional 45 horses housed in the exposed barn on the premises have been quarantined.
CDFA staff was on site at the event premises on February 11 to conduct a site assessment and assist in implementation of enhanced biosecurity measures, including twice daily temperature monitoring and prompt isolation of any horses displaying fever or neurological signs. CDFA will continue to actively monitor the situation.
For more information about EHV-1 read this EHV-1 Fact Sheet.
Information for this report was provided by the Equine Disease Communication Center.
For additional information visit the CDFA website.