Elderly people who develop serious illnesses after vaccination should immediately seek medical examination, and medication and other treatments should be administered under the supervision of a doctor. Generally, serious illnesses after vaccination include anaphylaxis, allergic laryngeal edema and so on. 1. Anaphylactic shock: patients will quickly develop dizziness, chest tightness, cold and clammy skin, and then blood pressure drop, breathing difficulties, consciousness disorder, and if not treated in time, cardiac arrest will soon occur, which is life-threatening. Doctors will give adrenaline, dexamethasone, iproniazine and other drugs according to the patient’s condition, and at the same time give intravenous fluids, oxygen, cardiac monitoring and other emergency measures. 2. Allergic laryngeal edema: the patient’s skin will have hives, itching, foreign body sensation in the throat, inspiratory laryngeal ringing, followed by inspiratory dyspnea, cyanosis, and even asphyxia. Treatment can be given epinephrine injection, cardiac monitoring, oxygen inhalation, etc., and an artificial airway can be established in severe cases. Therefore, the elderly should inform the doctor of their health condition before vaccination, and the doctor will evaluate and judge. If vaccination is possible, they should be kept under observation for 30 minutes after vaccination, during which time they should call the doctor immediately if they have any uncomfortable symptoms and be treated accordingly. If symptoms occur at home after the observation, the doctor should be consulted promptly.