HFMD is generally an acute infectious disease caused by enterovirus infections, the most common of which are enterovirus 71 and coxsackievirus A16. Among them, if HFMD involves the nervous system, encephalitis will occur, in which the main clinical manifestations are the emergence of poor mental health, lethargy, easy to startle, headache, vomiting, delirium, or even coma, limb shaking, myoclonus, nystagmus, ataxia, ocular dyskinesia, and so on. There is also muscle weakness or acute flaccid paralysis, convulsions. During physical examination, there may be positive meningeal irritation sign, weakened or absent tendon reflexes, positive baroreflexes, and so on.