The possible reactions and treatment methods of vaccination are as follows: a. Local reactions: within 24 hours of the baby’s vaccination, reactions such as redness, swelling, heat and pain appear at the vaccination site; redness and swelling with a diameter of 2.5cm or less is a weak reaction, 2.5-5cm is a medium reaction, and more than 5cm is a strong reaction. Light and medium reactions generally do not need to be dealt with, 1-2 days can subside on their own, strong reactions can be treated with hot compresses. Second, systemic reaction: mainly manifested as fever, 8-24 hours after vaccination, if the body temperature is 37.1-35℃ is a weak reaction, 37.6-38.5℃ is a medium reaction, and more than 38.5℃ is a strong reaction. In addition, there are systemic reactions such as dizziness, nausea and diarrhea, which are normal immune reactions after vaccination and do not require treatment. Strong reactions can be dealt with by physical or medication cooling methods. Abnormal reaction: mainly fainting, mostly occurs in fasting and nervous state, let the baby lie down and keep quiet, feed some warm water or sugar water, usually 3-5 minutes can recover by itself. Fourth, anaphylaxis: once anaphylaxis occurs, the baby should be sent to the hospital immediately to rescue.