News Article

Reported Outbreak of Neurological Equine Herpes Virus

Tuesday, 7 May 2013 - 10:00am

Reported Outbreak of Neurological Equine Herpes Virus (EHV-1) in North Devon
Many of you with horses will be aware that the neurological form of Equine Herpes Virus 1 (EHV 1) have been identified in North Devon.

St Boniface Vets have been in discussion with the Animal Health Trust (AHT) in Newmarket and other leading experts on the subject in order to present you with appropriate information.

The disease
Equine herpes virus is a common virus that occurs in horse populations world-wide. The two most common strains are: EHV 1, which usually causes abortion, respiratory disease and paralysis (the neurological form), and EHV 4 which causes respiratory disease and occasionally abortion. Most horses are exposed to some form of equine herpes virus during their lifetime and do not develop obvious disease or require euthanasia.

Clinical signs
The clinical signs of EHV 1 include: nasal and ocular discharge; swollen lymph nodes (glands); appearing lethargic; appetite loss; raised rectal temperature 102-106F/ 39-41C; ataxia (incoordination) and weakness in legs; increased tendency to lie down; straining to urinate.

How is it spread?
This can be directly from horse to horse, indirectly via handlers or infected tack or utensils or by aerosol to adjacent fields or buildings. Some horses are silent carriers, and intermittently shed the virus. The incubation period of the neurological EHV 1 is typically 5-6 days, but can be up to 10 days. Virus can be shed for up to 21 days after initial infection.

What should I do if I suspect the disease?
Firstly don’t panic! The AHT have advised that as the current outbreak is on stud (as opposed to a competition yard), and the yard has now been fully isolated with no movements on or off the premises, there is a relatively small risk to other yards or horses. Horse owners are advised to be vigilant and aware of clinical signs (off colour, possibly coughing often with nasal discharge, and 'wobbly' if it is the neurological form). If you are concerned the horses is sick then please speak to us for advice on what to do next. Specifically if you think your horse is off colour at all you should not be attending shows/hunting/ fun rides etc.

The AHT do not recommend vaccinating in the face of an outbreak. For vaccination to have any effect it needs to be a yard policy (so the whole population is covered). Once vaccination is started it needs to be continued year on year, (not just for the first 6 months when everyone is panicking)! However if you wish to discuss vaccination please do not hesitate to contact us.

If people are running shows/ going to events where there will be lots of horses, basic bio-security measures should be implemented:

  • A car's width between lorries/trailers being parked
  • NO nose-to-nose contact
  • Take your own water
  • Don't take the horse to a show if at all off colour!
  • The take home message is not to panic, but to remain vigilant and be responsible.

Further information, and concise guidelines aimed at dealing with an outbreak of EHV, can be found online at: http://codes.hblb.org.uk/index.php/page/32