This is going to be a long post, I'm sorry. I personally don't know much more than the average person about EHV 1. We've had many problems with EHV here in Maryland recently, at Pimlico (home of the Preakness) and the Bowie Training track. There is also confirmed EHV in a barn on the Eastern Shore. Many barns are doing self imposed quarnantines.
The following information was written by Dr. Laura Reilly. (reillylk@vet.upenn.edu)
Herpes myeloencephalitis is a very confusing disease, but here are a few important facts:
1. The cause is equine herpes virus 1 (EHV1), which can also cause respiratory signs and abortions. It is also known as rhinopneumonitis.
2. The virus is shed in respiratory secretions, and horses get it by inhaling the virus or from contaminated objects such as buckets, tack, etc.
3. On a farm, you may have just one horse or almost all of them affected. There may or may not have been known cases of respiratory disease or abortion beforehand. We don't know why some horses develop the neurological disease and others don't, but stress may play a role.
4. The signs of the neurological form include fever, incoordination, and weakness, usually most obvious in the hind limbs. There may be weakness of the tail and difficulty urinating and defecating. The horse may go down and be unable to get up. In most cases the signs show up about a week after exposure to the virus.
5. There is no specific treatment for EHV. Some horses recover completely, others do not, and if they are down the prognosis is poor.
<>6. The vaccine for Rhino does not seem to prevent the neurological disease, although some vets feel it may reduce the number and severity of cases.
So what should we be doing at our own farms?
I think we need to think carefully about moving horses around right now.
New horses should be investigated as to where they've been the last few weeks, and then isolated for 2 weeks (not a bad idea in any case).
Don't let horses mingle at riding lessons, shows, etc.
Disinfect buckets, etc if they have been used by other horses.
Monitor horses carefully for signs of disease, and call the vet right away if you suspect a problem, so a diagnosis can be quickly made.
Although the vaccine may not prevent the disease, we may want to booster our horses in case it could reduce the severity of illness.
**Note that animals known to be exposed to the virus probably should not be vaccinated- it may make things worse.
Kim Meier-Moranis first hand account of dealing with the outbreak of EHV1 at her farm
<>Information she wants all horseman to know.
This time of year there are lots of vans heading south. Make certain that you know who's been on that commercial van recently, if they have disinfected the van, with what disinfectant and how long ago it was disinfected.
<>A Virus generally cannot live outside of the body for more than 2-3 days.
Don't accept new horses into your barn without checking to make certain that they have come from a facility free of ANY contagious disease for a period of time extending at least 3 weeks. ASK! I STUPIDLY ASSUMED I WOULD BE TOLD IF THE HORSE CAME FROM A PLACE WITH A CONFIRMED FATAL VIRUS!
Common sense rules for bringing in any new equine:
Take the temperature and isolate the new horse for at least 2 weeks.
What to do if your horse has a fever?
Contact your Veterinarian.
<>The first sign of EHV SEEMS to be an elevated temperature, but the rules regarding Rhino are quite varied. I would isolate and catalog temperatures on any horses suspected of having Rhino.
For fevers, I generally give Bute (1gm 2x/day) but you should contact your veterinarian for any temperature of 102+.
How am I treating the horses on my farm during this epidemic? At the first sign of an elevated temperature, we give 12 (800mg?) tabs Acyclovir (sp) 3x/day. I believe this is human herpes medication. Elevated temperatures average IN MY BARN-(always assume this can vary) for 3 days. Any time during or after this phase, watch for neurological signs, such as:
a wobbly behind
unable to back up
tripping behind (unable to cross legs properly) when turned slowly in small circle
Fat hind legs may well be a pre-neuro sign
Dragging hind toes (and front).
<>It MAY be true that if they "go respiratory" (cough/snot) they won't "go neuro. I don't know, but have been praying for snot and cough anyway.
Neuro signs=BAD. At the onset of neurological signs, we begin jugging with DMSO and, gave Dexmethazone and Banamine along with the acyclovir. At the onset of neurological systems you have to plan for the worst case scenario, and it is prudent to move the affected horse(s) into an indoor/ a large shed/broodmare stall/near a big door/garage so if they go down you can get them up and out (this is gross but important-dead or alive.)
I've had 8 horses with elevated temperatures and 3 of these horses developed neurological symptoms. The first horse that was affected on my farm went neuro and was put down 24 hours later. This was my daughters 5 yr old Pony Club horse and a terrible loss for us all. If the horse goes down and can't get up it's nearly over and hardly any make it, or so I've been told. It happens fast, so you have to pay attention.
The second neuro case recovered from the fever and wobbled 24-36 hrs later. She's doing well now. Before she could not put head down to eat (no balance) so we made her a "table", and she had to be catheterized because their bladder can become paralyzed for 2-3 days.
The third neuros early symptoms were confusing, as he began with fat hinds. In hindsight we should have DMSOed right then, but with fat legs we started with Dex and Banamine. 2-3 days later when he began exhibiting definite neurological symptoms we did DMSO. By the way, there is no proof DMSO that works, but many veterinarians will still use this drug.
Where are we now?
On February 2, the second neuro case is being weaned off drugs. She wobbled last Wed. She has access to a small paddock with 1 friend and will it will take weeks/months to (hopefully) return to normal.
<>The case three neuro is better after 2 DMSO jugging days and still in the Indoor. FYI; this is my good eventer Merle, and he was the full brother to my daughters mare that had to be put down.
Bottom line: RESPECT this disease.
The trouble with Pimlico is that they told all track personal, etc, that the EHV1 outbreak was under control, and they allowed horses in and out of the track barns and tracks. They were even planning on racing on the 4th.
IT IS NEVER UNDER CONTROL UNTIL AFTER THREE WEEKS OF NO SYMPTOMS ON THE ENTIRE, REPEAT ENTIRE PROPERTY.
We don't want any more sick horses. Be notified and be careful.
Kim Meier-Morani
laissez faire, laissez aller, laissez passer, et laissez les bon temps roulez toute la nuit!
www.phyxiusphotos.com Christina Dale Equine Photography