I. General symptoms 1. Acute onset, incubation period 3-5 days, with prodromal symptoms such as low fever, general malaise, abdominal pain. The oral mucosa appears scattered painful corn to green bean size blisters, hands and feet appear maculopapular rash, herpes, initially maculopapular rash, later transformed into herpes, round or oval, about 3-7mm such as the size of a grain of rice, smaller than the chickenpox rash, hard texture, surrounded by a red halo, less fluid in the herpes, in the grayish white membrane can be seen under the dotted or flaky erosion surface. The rash does not leave scarring or hyperpigmentation after fading, but secondary infections often aggravate the skin damage. 2, outside the hands, feet and mouth, also seen on the buttocks and near the anus, occasionally seen on the trunk and extremities, drying up after a few days, fading, the rash is not itchy, no pain. 3. Individual children may develop generalized papules and blisters, accompanied by aseptic meningitis, encephalitis, myocarditis and so on. It may be accompanied by cough, runny nose, loss of appetite, nausea, vomiting, headache and other symptoms. 4. Some cases only show rash or herpetic pharyngitis. The whole course of the disease is about 5-10 days, and most of them can heal spontaneously with good prognosis and no sequelae. A few cases, especially those younger than 3 years old, may show encephalitis, encephalomyelitis, meningitis, pulmonary edema, circulatory failure, etc. Respiratory system manifestations are: shallow and difficult breathing, change of respiratory rhythm, cyanosis of lips, white, pink or bloody foamy sputum, sputum sound or wet rales can be heard in the lungs; 2, neurological manifestations are: poor mental health, drowsiness, headache, vomiting, easily startled, shaking limbs, weakness or paralysis; physical examination shows meningeal irritation, weakening or disappearance of tendon reflex; critical cases may show frequent convulsions, coma The circulatory system may show pallor, increased or slow heart rate, shallow, weak or even absent pulse, cold extremities, cyanosis of fingers and toes, and increased or decreased blood pressure.