Foot-and-mouth disease (FMD), also called hoof-and-mouth disease, is a highly contagious and economically devastating viral disease of cattle, swine, and other cloven-hoofed (split-toed) ruminants, including sheep, goats, and deer. The disease is highly contagious, for nearly 100% of exposed animals become infected, and it spreads rapidly through susceptible populations. Although there is no cure for FMD, it is seldom fatal, but it can kill very young animals.

The initial symptoms of the disease include fever and blister-like lesions (vesicles). The vesicles rupture into erosions on the tongue, in the mouth, on the teats, and between the hooves. Vesicles that rupture discharge clear or cloudy fluid and leave raw, eroded areas with ragged fragments of loose tissue. Erosions in the mouth result in excessive production of sticky, foamy, stringy saliva, which is a characteristic of FMD. Another characteristic symptom is lameness with reluctance to...