The vesicles start as small blisters, but then coalesce and produce bullae that rupture easily, leaving an ulcerated epithelial surface. In swine, lameness is usually the first sign, followed by the appearance of snout vesicles which rupture quickly. In lactating animals, lesions on the teats are common and the virus can be transmitted to calves.
Vesicles also appear on the coronary band, at the heel and in the interdigital space.
Lesions on the tongue heal rapidly through re-epithelialization but lesions on the feet tend to become complicated through secondary infection, delaying the healing process.