Preparing ahead of time and acting promptly when an outbreak occurs can help limit the spread of infectious disease in horses

You might notice lethargy or an untouched bucket of grain. Your horse hangs his head in the corner of the stall instead of nuzzling you for treats. Once you confirm a temperature of 101.5 F or higher, without an otherwise obvious cause, it’s time to take precautions to keep a potentially infectious disease from spreading.

“Similar to humans, horses get a variety of bacterial and viral infectious diseases that are easily spread among individuals,” says Sally DeNotta, DVM, PhD, Dipl. ACVIM, a clinical associate professor at the University of Florida College of Veterinary Medicine, in Gainesville.

These diseases have long affected equine populations and will continue to occur. “You can only be smart about how you manage it and avoid exposure,” DeNotta says.

Infectious Diseases Horse Owners Should Know 

Common equine infectious diseases that prompt quarantine include strangles, a bacterial infection associated with Streptococcus equi; equine herpesvirus (EHV), which can cause respiratory disease, abortion, or neurologic signs; influenza; and gastrointestinal infections caused by pathogens such as Salmonella and equine coronavirus.

Katie Flynn, BVMS, an international authority on biosecurity and U.S. Equestrian Federation senior veterinarian for equine health and biosecurity, says horse owners or managers who discover a fever should immediately contact a veterinarian to examine the horse and determine the infectious disease risk.

“The most ideal situation is immediately isolating any horse with a fever,” Flynn says, explaining that with strangles or EHV, the fever often appears before the horse sheds the bacterium or virus. “So, if you isolate the horse immediately, you’re removing the horse before it can expose other horses.”

Also clean and disinfect tack, buckets, brushes, stall cleaning tools, and other equipment the horse might have come into contact with, as well as surfaces such as stall walls and floors. But note that no disinfectant is effective without prior thorough removal of organic material.

Not all horses with fevers harbor an infectious disease. “We have (wound) abscess, colic, cellulitis cases,” Flynn says. If there’s one of those you can point to, then that’s not an infectious situation, but she recommends to always err on the side of caution