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This information is provided by Provet for educational purposes only.

You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.

Equine viral arteritis is a serious disease of horses and ponies 

The virus mainly affects non-thoroughbred horses and it has a worldwide distribution. Signs of infection vary, but may include :

  • No signs at all - in other words some infected horses have sub-clinical disease. This can be a particular problem in stud stallions because the virus can be transmitted in their semen
  • Abortion
  • Generalised depression
  • High body temperature (fever)
  • Fluid collection (oedema) causing swelling in limbs, or along the ventral surface of the body due to poor circulation.

This virus is transmitted in two main ways :

  • Aerosol spread
  • In infected semen

There is a blood test that can be used to detect horses with serological evidence of infection (antibodies against the virus) - in the UK this is available from the Animal Health Trust in Newmarket.

It is such an important disease that in the UK the following regulations apply :

  • Horses being imported from a country with known or suspected Equine Viral Arteritis must be isolated for 21 days and blood tests performed on arrival and after 14 days in isolation.
  • Veterinarians must notify suspect cases (under the Equine Viral Arteritis Order 1995 and Equine Viral Arteritis Order (Northern Ireland) 1996) and infected stallions are subject to specific movement restrictions.
  • Horses should be tested for equine viral arteritis before mating

Vaccines are available against equine viral arteritis in countries in which the disease is present. In other countries (such as the UK) vaccination may only be allowed under special circumstances. Many countries will refuse to admit a horse with a positive serological test unless it can be proved by a Veterinary Certificate that the horse acquired the circulating antibodies through vaccination.


Updated October 2013