At Rancho Sierra Vista Equestrian Center in San Juan Capistrano, California, bad news came on the heels of the new year. "A little cough had been making the rounds of the barn, and we were on alert for that," recalls trainer Cathy Hanson, who stables 30 horses at the 350-horse multidiscipline facility. "But in early January one horse developed neurological signs, and that prompted testing."
The blood test came back positive for a form of equine herpesvirus-1 that can cause potentially fatal neurological disease in horses. "EHV is everywhere, and it's super-contagious," Cathy says. State animal health officials were called in, and on January 10 the facility was quarantined.
An outbreak of contagious disease is a nightmare at any barn, let alone a facility home to so many horses. This was the first such incident for Rancho Sierra Vista, but it was just one of several outbreaks that have put riders on edge around the United States in recent months. The list of disease-causing organisms that spread horse to horse includes viruses like EHV and equine influenza as well as bacteria like Streptococcus equi, which causes strangles. How can you protect your horse?
"We won't be able to prevent all cases of these diseases," says Josie Traub-Dargatz, DVM, MS, DACVIM, an equine disease expert at Colorado State University. But that doesn't mean you're helpless. In this article, Dr. Traub-Dargatz explains how you can assess—and reduce—the risks your horse faces. Those risks are greater if he lives at a big commercial boarding stable or is a regular on the show circuit than if he lives in your backyard and just makes a circuit of the pasture. But he faces some danger of infectious disease anytime he comes in contact with other horses.
Get the Facts First
Word of disease outbreak travels fast these days, via Facebook, Twitter, online forums, text messages, and email. "Social media can get information out extremely quickly," Dr. Traub-Dargatz says, "but the accuracy of the information may be open to question." To assess risk, you need to separate facts from rumors and exaggerations.
Some contagious equine diseases are reported to state animal health officials, and that makes it fairly easy to get reliable information about an outbreak. For example, in California, neurological cases caused by EHV-1 must be reported to the state Department of Food and Agriculture. During the San Juan Capistrano outbreak this allowed everyone to get frequent and accurate updates on the CDFA website, where outbreaks are categorized by county instead of by naming specific facilities. Reporting requirements for equine diseases vary state to state, so check with your state's animal health officials to find out which diseases are reportable where you live.
Reporting requirements helped check a multistate outbreak in 2011, when more than 400 horses were exposed at a cutting-horse event in Utah and went home to barns in 19 states and Canada before the first case was recognized. State and federal officials worked closely to track the horses and get accurate, timely information to the public.
When the disease isn't reportable to state animal health officials, getting information is much more complicated. For instance, California doesn't require reporting for equine flu or common forms of EHV that cause respiratory disease in horses and abortion in pregnant mares. Where should you turn? Your veterinarian is the most likely source of reliable advice, but with no central clearinghouse for information it can be a challenge to get the facts.
The American Association of Equine Practitioners has formed a task force to develop a communications plan for disease outbreaks. (This is part of an effort by the American Horse Council to create a national equine health plan.) "The goal is to make sure owners and managers of events and horse facilities, industry associations, extension agents, horse councils and veterinary practitioners all have accurate information quickly, acknowledging that the source of that information may vary," Dr. Traub-Dargatz says.
The task force will develop a draft plan and send it to the American Horse Council for industry input, so there's an opportunity for horse owners and event organizers to get involved, she adds. "Think about what diseases you need to know about and what your concerns are. You can voice those concerns to breed or discipline associations or to your state horse council, which all communicate with the AHC."