Most of the precautions to be taken after the booster shot are similar to those for the previous shots, with a 30-minute stay, avoidance of bathing for 24 hours, attention to diet, rest, and observation for any adverse reactions. A booster shot is a dose of vaccine that is given after a period of time after vaccination has been completed, and which needs to be given again in order to increase the level of antibodies and better maintain the immunity of the antibodies. Common vaccines that require booster shots include hepatitis B vaccine, rabies vaccine, and new coronavirus vaccine. After the booster vaccination is completed, it is necessary to observe for 30 minutes to see if there is any serious adverse reaction, and only leave if there is none; the vaccination site should avoid contact with water for 24 hours, otherwise it may lead to localized infection; after the booster vaccination, the main focus is to eat a light diet, and to avoid drinking alcohol and spicy and stimulating food. After the booster injection, the vaccinated person may have symptoms such as fatigue, fever, headache, etc.; there will also be swelling and pain at the vaccination site. The above reactions can usually be relieved on their own within 2-3 days and do not require treatment, but if the symptoms are more severe or last for a longer period of time, it is necessary to go to the hospital for consultation and treatment.