What is equine herpes virus?

Equine herpes virus (EHV) is found in horse populations worldwide. EHV-1 causes mild respiratory disease but is better known for more serious complications including abortion and neurological diseases. EHV-4 causes respiratory disease and may cause abortion in some mares.

At what age are horses at risk?

Respiratory disease caused by EHV-1 and EHV-4 is most commonly reported in young horses. Once infected, horses can carry the viruses even after they have recovered. Over the horse's lifetime, the virus can reactivate and cause a relapse of symptoms as well as become a source of infection for new outbreaks.

Some signs to look for:

  • Pale yellow nasal discharge
  • Enlarged lymph nodes
  • Occasional episodes of coughing
Vet giving tetanus vaccine shot