The dangers of the New Crown Vaccine Booster Shot generally refer to adverse reactions, usually weakness, headache, diarrhea, and redness, swelling, and hardness at the injection site. The New Crown Vaccine booster is usually recommended to be given about 6 months after the 2nd New Crown Vaccine dose to allow for a higher persistence rate of antibody production and better protection. Some people may experience fever, transient weakness, headache, diarrhea, and redness, swelling, and nodules at the injection site. Occasionally, adverse reactions such as rashes at the injection site or itching at non-vaccinated sites, or pain in muscles and joints may occur. The above hazards are less likely to occur in patients who are observed on the spot for 30 minutes after receiving the booster shot of the new crown vaccine. Even if fever and other symptoms occur, they can be relieved more quickly by resting more and drinking more water. If fever or other discomfort persists, prompt medical attention is recommended.