Initially, there may be mild upper sensory symptoms. The child salivates and refuses to eat due to painful oral ulcers. Oral mucosal rash appears relatively early, initially as a corn-like maculopapular rash or blister surrounded by a red halo, mainly on the tongue and both cheeks, and often on the lateral side of the lips and teeth. The rash is not itchy, and the papules turn from red to dark in about 5 days and then fade; the herpes is round or oval and flat, with cloudy liquid inside, with a long diameter in line with the direction of the skin, such as the size of a soybean, generally without pain and itchiness, and leaves no trace after healing. Hand, foot and mouth lesions may not all appear in the same patient.