Disease Alerts

Updates on current disease outbreaks are listed here as they occur and will include the date listed, disease name, location and current status. Specific premises will not be named but the general location by town, county and state will be listed. When locations, events or horses are at risk they will be listed. Updates will be posted as they are received.



Equine Herpesvirus- Neurologic
Riverside County, CA
Outbreak Identifier: 5455
Alert ID: 2848
December 23, 2022
Confirmed Case(s) - Official Quarantine

California Department of Food and Agriculture

Number Confirmed: 1
Number Exposed: 4
Facility Type: Private Facility
Age: 14; Gender: Mare; Breed: Quarter Horse (QH); Onset of Clinical Signs: 12/17/2022
Clinical Signs: Mild neurologic; Horse Status: Affected And Alive; Vaccination Status: Vaccinated
Comments: A 14-year-old Quarter Horse mare in Riverside county displaying mild neurological signs was confirmed positive for Equine Herpesvirus Myeloencephalopathy (EHM) secondary to Equine Herpesvirus-1 (EHV-1, non-neuropathogenic strain) on December 22nd. The mare is alive and under veterinary care. The mare and four (4) exposed horses on the home premises were quarantined. There has been no recent history of travel on or off this premises. For more information, go to https://www.equinediseasecc.org/equine-herpesvirus.