THE Irish Equine Centre has confirmed four cases of EHV-1 neurological disease [equine herpes visus] on a thoroughbred stud farm in Leinster and two cases on a mixed farm (sport horses and thorougbreds) in Munster. Voluntary movement restrictions are in place and the horses on both premises are being monitored by PCR and serological testing.

Q: WHAT IS EHV-1 NEUROLOGICAL VIRUS?

EHV stands for equine herpes virus. This is a family of viruses found all over the world. Some types have no serious side effects but EHV-1 can be fatal. There are four EHV-1 manifestations - respiratory diseases, abortion, neonatal death and neurological. The current outbreak is neurological which can appear suddenly.

Q: WHAT ARE THE SYMPTOMS?

Neurologic disease appears suddenly and progresses rapidly, peaking within 48 hours. Clinical signs include:

>Nasal discharge

>Incoordination

>Hind limb weakness

>Loss of tail tone

>Lethargy

>Urine dribbling

>Head tilt

>Leaning against a wall to maintain balance

>Inability to rise

The respiratory version of EHV-1 typically takes a few days to incubate. Typically the infected horse has a two-phase fever, spiking on day one or two and again on day six or seven. There is often a discharge from the nose and eye but not much coughing. The horse's lymph nodes (under the jaw) can be enlarged.

Q: HOW DOES IT SPREAD?

EHV-1 is contagious and is spread by direct horse-to-horse contact, usually through nasal secretions. It can also be spread indirectly through contact with physical objects that are contaminated, such as human hands, clothing, buckets, rags, etc. The air around an infected horse can also be contaminated.

Q: WHAT SHOULD I DO IF I SUSPECT A CASE ON MY PREMISES?

Isolate the horse(s) in question and contact your veterinary surgeon immediately. Where disease is suspected, the attending veterinary surgeon should take the following samples and submit them to a laboratory. Check the horse's temperature regularly and record it.

There are no legal notification requirements for EHV in Ireland although it is advisable to inform the relevant breeders’ association if infection occurs.

Because the disease spreads easily between horses and can have severe consequences, it is very important to alert owners of horses which might be at risk of infection through contact with your horse or premises following an outbreak.

Q: IS THERE A VACCINE?

Yes, vaccines are available though there have been shortages in supply at times in recent years.

For further information, contact the Irish Equine Centre on 045 866266 or see the attached booklet.

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