entries and travel plans. Keep exposed horses on your property—and don't let new horses come in—during the outbreak.
- Monitor healthy horses. Take temperatures twice daily, watch for other signs of disease and quickly isolate new cases.
- When the sick horse recovers, wait for a green light from your vet before you return him to the group. He may seem OK, but he could still be spreading infection.
- Thoroughly clean and disinfect the stall and all equipment after isolation ends. (You can find disinfection guidelines online at the Iowa State University Center for Food Security & Public Health website, www.cfsph.iastate.edu/Disinfection.)
Some steps aren't feasible for every barn. For example, a large facility with ample space and staff might have a designated competition area separate from resident horses. That would be impossible at most smaller barns.
If you board your horse, you may have little control over many of these procedures but every stable should have a biosecurity plan, Dr. Traub-Dargatz says, and boarders as well as management can help shape it. "A boarding facility might want to hold a 'town hall' meeting where owners, trainers, managers and veterinarians discuss what the concerns are and what the plan might be," she suggests.
Where several veterinarians treat horses at the same facility, management should choose one to advise on biosecurity, Dr. Traub-Dargatz suggests. "Developing a biosecurity plan may seem simple at first, but you really need to think through the details and make sure everything is in place and that there is agreement on the plan," she notes. She recommends doing a walkthrough of your facility with someone who understands infectious disease. "This is where the details come into focus. For example, are you telling people to wash their hands, but there's no soap and water? They're not going to do it."
Once the plan is in place, be fair and consistent in applying it. "Make sure everyone knows what decisions have been made and why," she says. "If people understand the protocols and reasons for them, they're more likely to comply."
Quick action limited EHV-1 infection to a few sections of Rancho Sierra Vista Equestrian Center and kept it from spreading to neighboring facilities that were home to another 650 horses. Cathy Hanson reports that management "jumped on the situation." Some shared facilities were ruled off limits, wash stalls and equipment were disinfected after each use and hand sanitizers and footbaths were at the ready. Quarantine information was also posted on the center's website.
"The disease itself doesn't last long, and most horses don't get very sick, but with so many horses here we knew it could take months to run its course through the facility," Cathy says. To shorten that time and to stop the spread, the center arranged to test all 350 horses for EHV-1 and use portable stalls to create an isolation area for the horses who tested positive.
In the end 16 horses tested positive, but only the first horse developed neurological signs, and that horse recovered. At the Empire Polo Club, too, which also provided regular updates about the situation on its website, the first case was the only one. Quarantine was lifted at both facilities February 14.
At press time in mid-March, CDFA reported that two horses who attended the same California event had tested positive for the non-neuropathogenic strain of EHV-1.
This article originally appeared in the May 2012 issue of Practical Horseman magazine.