If your horse travels or is exposed to unfamiliar horses on a regular basis, talk to your veterinarian about regular immunization against equine influenza. While it’s true that influenza viruses do evolve to bypass the horse’s immune defense, you can provide some short-lived protection through vaccination.
But vaccinate before your horse gets sick. Signs that your horse may be suffering the flu are similar to those we get when we come down with a common cold: dry cough, runny nose, fever, depression and loss of appetite. Like the common cold in humans, treatment for equine influenza includes lots of rest; most horses recover in about 10 days, but some require several weeks for recovery.