EHV is a virus found in horses virtually all over the world. Once a horse is infected, the virus remains in the system and can reactivate in the future. Of the four main types, EHV-1 and EHV-4 are the most common in the UK.
The virus usually hits the news when EHV-1 causes paralysis, which can range from mild uncoordination of the hindlimbs, to total paralysis where the horse is unable to stand. This can be very alarming for horse owners, can occur at any time of the year and in horses over the age of five years. When paralysis is seen, the horse will usually have been infected or reactivated the virus between one and two weeks earlier. However, whether paralysed or not, this virus affects the wellbeing of horses and if you spot a runny nose, breathing difficulties, coughing or raised temperature, be suspicious and take action – especially if horses come and go from your yard a lot and could have been in contact with other horses at events, rides or training.The virus usually hits the news when EHV-1 causes paralysis, which can range from mild uncoordination of the hindlimbs, to total paralysis where the horse is unable to stand. This can be very alarming for horse owners, can occur at any time of the year and in horses over the age of five years. When paralysis is seen, the horse will usually have been infected or reactivated the virus between one and two weeks earlier. However, whether paralysed or not, this virus affects the wellbeing of horses and if you spot a runny nose, breathing difficulties, coughing or raised temperature, be suspicious and take action – especially if horses come and go from your yard a lot and could have been in contact with other horses at events, rides or training.
EHV respiratory infections are mostly spread from horse to horse through droplets from coughing and snorting. EHV droplets do not travel long distances (no greater than 50m), so reducing close contact between horses will greatly reduce risk of spread. Infected aborted fetuses and their placentas can be dangerous sources of EHV for other pregnant mares, especially if the abortion occurs within restricted stabling space. The virus can be transmitted by both people and equipment because it can survive for up to a month once it has been shed by a horse.
Call your vet immediately and consult the HBLB Code of Practice if you are dealing with an abortion.
Your vet will advise specifically on how to isolate affected horses and on the hygiene/cleaning procedures to be followed, but in general...
British Equestrian EHV INFORMATION SHEET