MMR vaccine is a live attenuated vaccine, individual babies will show symptoms of fatigue and fever 1-2 weeks after vaccination, which usually last 1-2 days and can subside on their own, and most of them do not need to be treated. After the corresponding fever symptoms appear, babies should rest properly, ensure sufficient sleep, drink more water to promote metabolism, and the body temperature can subside on its own in about 3 days, and they should also pay attention to keeping warm to prevent cold symptoms. If the fever causes discomfort, you can apply physical methods to cool down, such as warm water baths, alcohol baths, etc. If the baby’s body temperature exceeds 38.5℃, antipyretic and analgesic drugs such as ibuprofen and acetaminophen can be given as appropriate to reduce fever. In addition, if the fever exceeds 3 days or the body temperature increases abnormally, you should promptly visit the pediatric internal medicine department. If your baby has a fever after vaccination, you must take better care of him/her, pay attention to always observe his/her condition and give him/her more water. When abnormalities are found, you should immediately go to the pediatric internal medicine department of the hospital.