From Endurance to Dressage
EHV-1/EHV-4, EHM, and Your Horse
The social media sites and blogging sites were blazing hot on Sunday with talk about the EHV-1. The possibility of a fatal disease striking your horse prompts many people to take evasive action. I don't tend to get too excited about internet rumors and reports of horrible news until I get a first hand account of what is happening. And even then I don't panic. I also like to hear it being said from an expert. I scoured the internet for non-inciting news yesterday and landed on several blogs and sites that gave honest information that didn't seem to exaggerate the seriousness of the "outbreak." If you're interested in reading some of these posts, scroll down to the bottom of this post.
Many of you may not know the difference between Equine Herpesvirus-1 and Equine Herpesvirus Myeloencephalopathy. First of all, there are actually nine equine herpesviruses, but only three of them, EHV-1 (the one we're worried about), EHV-3 (which causes a venereal disease), and EHV-4 (which causes a non-fatal upper respiratory tract infection) pose a serious risk to domesticated horses.
The vaccine that we give for EHV-1/EHV-4 (Rhinopneumonitis) does not protect against EHM. There is no vaccination for EHM. Once affected with EHM, the standard form of care is simply supportive. Treatment may include intravenous fluid and anti-inflammatory drugs.
By about age two, many horses become infected with EHV-1 by contact with their dam. The virus is usually inactive, but may become reactivated by stress or contact with an affected horse. EHM is caused when the EHV-1 undergoes a mutation of the genome. [a very, very simplistic explanation!]
So what can we do about EHM? Interestingly, the literature I read strongly urges horse owners to NOT remove any horses from a site where a suspected case of EHM has been present until cleared by a veterinarian. Oops. That's what just happened. So what do we do now? Don't share tack, brushes, feed buckets, or any other communal items. Wash your hands and change clothes if you even suspect a horse might be ill. The disease is spread by horse to horse contact. DON'T allow horses to touch noses.
All the websites and blogs are reporting essentially the same thing. A case or two of the nuerologic version of Equine Herpesvirus-1 have been confirmed with a few other horses being treated as though they are positive. Most experts are recommending a quarantine period for animals suspected of being infected. The next few days should reveal a more complete picture.
For More Information:
5/18/2011 03:59:54 am
Dear Ms. Sweaney
5/18/2011 12:28:18 pm
5/22/2011 05:17:46 am
When you talk about a mutated EHV-1 virus (in this case, EHM), you're talking about a new virus. Just like human flu viruses, the old vaccines don't cover the new mutation. So how can the standard rhino viurses protect againt the mutation?
5/22/2011 06:21:05 am
GB - Thank you for sharing! The purpose of this blog, as I've stated before, is to share information about equine health, dressage, and endurance riding, particularly as it relates to equine health!
5/22/2011 12:12:36 pm
It is incorrect to say this is passed by horse-horse contact, and mention touching noses. While this may be true, the correct thing to say is that this is both droplet- and aerosol- transmitted, so horses need to be a lot farther away than nose-nose. Recommendations I've read mention at least 30 feet distance.
5/22/2011 12:18:35 pm
Also, this is not about a "case or two". There are almost 40 confirmed cases reported officially now, and a total of about 1000 horses have been considered "exposed". A total of 174 facilities in the US and Canada are considered exposed and under quarantine, either voluntary or madatory. This is all on USDA's Animal and Plant Health website.
5/22/2011 11:11:47 pm
Gwen - thanks for writing and sharing!
Comments are closed.
About the Writer and Rider
I am a lifelong rider.
I began endurance riding in 1996 where I ultimately completed five, one-day 100 mile races, the 200-mile Death Valley Encounter, and numerous other 50, 65, and 75 mile races. I began showing dressage in 2010.
Welcome to my dressage journey.
About Speedy G
Speedy went from endurance horse to dressage horse. After helping me earn a USDF Bronze medal in the summer of 2020, he is now semi-retired. Speedy is a 2004, 15'1 hand, purebred Arabian gelding. His Arabian Horse Registry name is G Ima Starr FA.
Izzy was started as a four-year old and then spent the next 18 months in pasture growing up. I bought him as a six-year old, and together, we are showing at the lower levels. He is a 2008, 16'3 hand warmblood gelding. His Rheinland Pfalz-saar International (RPSI) name is Imperioso.
National Rider Awards
State Rider Awards
State Horse Awards
CDS Sapphire Rider Award
Third Level: 63.514%
Third Level: 62.105%
2023 Show Season
(r) Ride-a-Test Clinic
2023 Show Schedule
2023 Completed …
2023 Qualifying Scores
Regional Adult Amateur Competition (RAAC)
Qualifying Training Level
3 Scores/2 Judges/60%: