EHV-1 and EHV-4 are alphaherpesviruses that generally bring to mind respiratory disease, abortion and neurologic disease. Horses are also hosts of EHV-3, an alphaherpesvirus that causes equine coital exanthema. Kate L. Hepworth-Warren, DVM, DACVIM, reminds us of the often forgotten EHV-2 and EHV-5, gammaherpesviruses are quite prevalent in the equine population, as well. Despite their inclusion on some respiratory panels, the importance of EHV-2 and EHV-5 in horses with respiratory disease is uncertain, although each virus has some link to disease.
Source: DVM 360, April 30, 2020. Link.
Individual and co-infections with EHV-2 and EHV-5 may play roles in respiratory disease, ocular disease and poor performance, but at this time the significance of these viruses remains unknown.” – Kate L. Hepworth, DVM, DACVIM