Equine Herpesvirus (EHV)
EHV is a common virus in the horse population and has several genetic strains.
Common strains, EHV-1 and EHV-4, cause a mild respiratory disease.
In most cases, horses recover from the virus within a few weeks.
Vaccinations are available to prevent the respiratory disease and abortion caused by EHV-1 and EHV-4.
Equine Herpesvirus Myeloencephalopathy (EHM)
EHM is a neurologic disease that can develop, in rare cases, in a horse infected by EHC.
EHM is usually caused by the EHV-1 virus. In extremely rare cases, EHV-4 can develop into EHM.
There is no cure or vaccination for EHM and prognosis for horses who test positive for EHV and develop neurologic signs of EHM can be poor.