EHV – What You Need to Know

581818_10151814104748858_685132232_nMost people will have heard of the two recent outbreaks of Equine Herpes Virus (EHV) in the South West. The most recent case at the Beaufort Hunt Stables in Badminton is of particular concern due to the proximity of Badminton Horse Trials which is due to take place in 6 weeks. At the moment the horse trials are not at risk of cancellation but the situation remains under review and expert advice is being sought.

EHV 1 and 4 are responsible for two forms of disease in horses. One is abortion of pregnant mares, the other respiratory/neurological disease. The virus has an incubation period of 2-10 days and is spread via horse to horse contact either directly, over short distances by aerosol transmission or via transfer on the hands or clothing of people or tack and equipment. The virus is actually very fragile in the environment and is very susceptible to most common disinfectants. Testing can be carried out via bood samples or nasal swabs and results are usually received within 48hrs.

What to look out for:

One of the three disease forms: abortion, respiratory disease or neurological disease.

Respiratory signs – coughing, nasal discharge, temperature above 38.5C, inappetance, dullness.

Neurological signs – incoordination, staggering, recumbency, difficulty urinating/defaecating, temperature above 38.5F

If you have a horse with any of these signs and are close to the outbreak, or have had hunted with the Beaufort, please telephone  your vet as a matter of urgency. If you have a horse with any of these signs but do not have a direct link to the outbreak please still call your vet for advice – the link to the current outbreak in Badminton from the Heythrop outbreak was not immediately obvious.


Preventative Measures:

Many of these are good common sense disease control measures that should be in place in yards anyway but bear repeating.

Isolate any new horses coming onto the yard for a minimum of 10 days. Make sure separate equipment is used for these horses and members of staff clean and disinfect their hands and ideally change their clothing after tending horses in isolation. Ideally do these horses after the rest of the yard has been finished.

Make sure transport is cleaned and disinfected between horses – farmers have to do this as a matter of course and it is surprising that more horse owners don’t.

Isolate any horses showing any of the above signs.

If you are in the immediate area of the outbreak limit movements on and off the yard and consider staying at home until the outbreak is under control.


Although there is an EHV vaccine vaccination in the face of an outbreak can actually make matters worse. While the vaccine can limit clinical signs and decrease the virus shedding of an infected horse (i.e. how likely it is to transmit it to another horse) it is not a failsafe.

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The Eventing Vet