A 13-year-old Quarter Horse mare in San Bernardino County was euthanized due to neurologic equine herpesvirus (EHV-1) on October 29, according to information from the California Department of Food and Agriculture. The diagnosis was confirmed on November 5. This mare does not have any epidemiological links to other EHV-1 cases in California, and there has been no recent horse movement off the property.
Twenty horses on that property have been exposed and are under quarantine with enhanced biosecurity measures. Those measures include twice-daily temperature monitoring.
For more information about neurologic herpesvirus (or equine herpesvirus myeloencephalopathy, or EHM, read this AAEP Fact Sheet.
Information for this report was provided by the Equine Disease Communication Center.