First of all, there's no need to panic. Be smart? Yes. Be aware? Yes. Panic? An emphatic "no."

Pockets of the horse industry have wrestled with a neurologic equine herpesvirus-1 (EHV-1) outbreak before, and they have recovered and gone back to business as usual. The current state of quarantined barns and hospitals and smattering of canceled shows is inconvenient, expensive, and frustrating, but these preventive measures are necessary and will be worth the trouble in the long run. We don't want to see more horses in additional states affected.

This outbreak can cause our hearts to palpitate because neurologic illness in a horse is ugly, and how these viruses work and are spread can be confusing and seemingly unpredictable. However, there is good news: There are some very smart/savvy veterinarians treating neurologic horses and catching cases early. Also, if owners with horses that attended the Ogden show monitor these animals (and any in-contact horses) vigilantly for fever and other signs of illness; if they work closely with their veterinarians; and if they stay put on their farms, the situation will become a nonissue.

This particular neurologic EHV-1 outbreak is interesting to me because it's much more high-profile than the others I've followed in the 12 years I've been at The Horse. I find myself asking why.

  • Is it that the first-confirmed cases all have a particular show in common, so the situation is "relatable" for owners ("That could have very easily been me.")?
  • Is it the widespread use of social media, with a steady stream of posts on Facebook and Twitter (some accurate, some not)?
  • Is it because there are confirmed cases in multiple states (we're not just talking about a few adjacent counties)?

Regardless of what it is about this outbreak that has people on edge, simply brushing up on your EHV-1 knowledge is important, if it does nothing more than calm your nerves and give you a reference point for disease caused by the virus, should you ever encounter it. Our news editor, Erica, has spent many hours on the phone this week with veterinarians and state departments of agriculture collecting facts to educate readers. If you haven't already seen them, check out these two stories for a recap on EHV-1 and how it manifests (The Top 5 Things You Need to Know about Neurologic EHV-1, and Equine Herpesvirus-1: Minimizing Costs, Dispelling Myths). And here's an article we ran a few years back on the different types of EHV and what veterinarians have learned about them. 

In reflecting on the past week of industry reaction, here are some things that I feel should be pondered:

  • An outbreak of neurologic EHV-1 doesn't mean that someone has been irresponsible. When case reports are popping up here and there, it's in our caring and passionate nature as horse owners to want to place blame and point out an error or lapse as a cause. Several veterinarians said that the source of the illness might be a subclinical shedder, meaning a horse that didn't even show clinical signs of a disease--and still might appear completely healthy--might have simply cleared his nasal passages while being led down a barn aisle at the Ogden show. Similarly, owners whose horses were exposed (without the owners' knowledge) to a shedder may have brought their normal-acting horses home with no awareness that these animals may have been exposed. Any speculation about irresponsible management is unnecessary and unfortunate.
  • Preventive measures go a long way in reducing spread and expense. A veterinarian whose hospital was quarantined in a past neurologic EHV-1 outbreak mentioned this week that the ordeal cost his clinic more than a million dollars. Being responsible is, in fact, expensive, and by keeping your resident horses home; by watching any that may have been transported to your farm recently (and you're not sure their point of origin) and separating them from your resident herd; and by taking temperatures daily of horses that attended the Ogden show or have been exposed to those travelers, you can prevent further spread. As a bit of a biosecurity geek, I have compiled information on preventing disease spread in the past.
  • Historically, there's been no centralized location for collating EHV-1 neurologic cases, although the USDA has begun to keep a list of cases. Until that list went live, Dr. Scott Weese, a veterinarian at the University of Guelph's Ontario Veterinary College, was keeping track. By the way, he and his colleagues update a fascinating infectious disease blog that I encourage you to visit. Since EHV-1 neurologic disease is not a reportable disease in every state or province, gathering such information can be difficult. Watch the USDA site for domestic updates and the EquID blog for Canada numbers. The AAEP has some great information on their resource page. And Erica will do her best to get the most up-to-date, accurate information that she can find for her story updates.
  • Keeping that in mind, work closely with your veterinarian to assess your horse's risk in light of reports. A "confirmed" or "suspect" case can mean several things. As a veterinarian friend pointed out to me yesterday, case counts have the potential to be confusing and/or misleading, because a confirmed case might mean a laboratory-confirmed diagnosis on a horse that exhibited neurologic signs. Or, as another example, it might mean a horse in proximity to other cases tested positive for EHV-1 without showing any neurologic signs. (We've tried to designate in our updates if the horses were neuro cases.) And, as at least one veterinary source has pointed out this week, EHV-1 is a very common virus to find in horses, and the majority of horses are exposed early in life and become latently infected (they don't show signs of illness) for their lifetimes. My friend posed the question of whether any of the reported positives could be latent infections that simply happened to be tested because of their proximity to the current outbreak ... and maybe they just got over an EHV-1 respiratory infection ... or recently had an EHV-1 abortion unrelated to the current outbreak ... or maybe they have other causes of neurologic signs. Confusing, yes? There's also the issue of where these cases are--is it even a county near you? This is why working with your veterinarian is so very important. He or she has the experience and insight to advise you on what precautions need to be taken, given the case information available.
  • By reporting on this continually, we're giving horse owners coordinates on what's happening. My goal is to help eliminate the hysteria. The daily updates have been worth it to me if just one person realizes it might be a good idea to keep an eye on a recent equine addition to his or her farm, separating him from their resident herd if they're not sure where the horse has been. Better safe, as they say. It's also worth it if one person who's panicking reads our reports and realizes, "Oh, my horses never leave the farm, and nobody has been out to an affected premises has visited my horses. We're fine." My hope is to educate. In that light, we're having a live webinar on Tuesday at 8:00 p.m. Eastern that I hope you'll attend.

I heard that a conference call Thursday for veterinarians about the current EHV-1 situation garnered more than 250 attendees. Veterinarians are educating themselves on how cases in the current outbreak are presenting, and they're brushing up on case treatment methods, and that's great to hear. We've got a caring, well-informed population of equine veterinarians, and that inspires me daily.

So, considering there's a veterinarian population wielding the latest EHV-1 knowledge, a horse-owning population armed with accurate information and being vigilant about transport and watching for fevers, and the inevitable quieting of this outbreak as biosecurity measures are taken, this thing could be done soon. There's really no reason to panic.

Your turn: Why do you think this EHV-1 outbreak has been talked about more than other outbreaks in recent years? Have you been touched by this outbreak?