Is encephalitis caused by hand, foot and mouth disease serious?

It's serious. Hand, foot and mouth disease is caused by a variety of enteroviruses, the most common is coxsackie virus A16 and enterovirus 71, hand, foot and mouth disease mainly occurs in children under the age of five. General cases of good prognosis; a few severe cases of rapid disease progression, in the onset of 1-5 days or so show meningitis, encephalitis, brain stem encephalitis is the most dangerous, encephalomyelitis, pulmonary edema, circulatory disorders, etc. Very few cases in critical condition, can cause death, survival cases may be left with sequelae. When the central nervous system is involved, it may be manifested as poor spirit, somnolence, headache, vomiting, delirium and even coma; limb shaking, myoclonus, nystagmus, ataxia, eye movement disorder, acute flaccid paralysis, convulsion, etc. Physical examination shows meningeal irritation sign, tendon reflex weakening or disappearance, and positive Pap sign. Children with central nervous system are more common within two years old.