Equine coital exanthema (EHV-3)

Veterinary advice should be sought before applying any treatment or vaccine.

Equine Coital Exanthema (EHV-3)

Equine Herpesvirus 3, EHV-3, Equine Herpes Virus 3, Equid Herpesvirus 3

Equine coital exanthema (ECE) is a highly-contagious, venereally transmitted disease of breeding horses caused by the equine herpes virus 3 (EHV-3). ECE is found in breeding mares and stallions worldwide. ECE is characterized by the development of lesions on the external genitalia of horses. Lesions might also occur on teats of mares and muzzles of nursing foals.

Clinical signs
During the early stages of the disease, circular lesions appear on the horse's genitals. Vesicles are initially present which rupture and result in small, crater-like lesions, often with a pustular center.

ECE is transmitted through direct skin-to-skin contact during breeding activities between horses, during artificial insemination, from the hands of people interacting with horses, or from the lips and nose of horses interacting with one another. There is also a risk of the virus spreading by either fresh or frozen semen as well as by artificial insemination and embryo transfer.

Incubation period
ECE has an incubation period between 7 to 10 days.


Oral mucosal ulcerations on tongue and lips
Circular lesions on genitals
Redness and swelling
Loss of libido
Refuse to mount
Frequent urination
Vulvar discharge
Arching of the back


  • History
  • Clinical signs
  • Physical exam
  • EHV-3 VN test
  • EHV-3 virus isolation



Topical antibiotic cream


Scientific Research

General Overviews

Causative agent