There are generally no after-effects of the third dose of the New Crown vaccine. After-effects are the effects that occur when the drug concentration is metabolized in the body and reaches a concentration below the effective concentration, which in most cases refers to negative effects. The third injection of the new crown vaccine has been popularized and promoted in China, and no adverse after-effects have been found. After receiving the third dose of New Crown Vaccine, there is a possibility of localized pain, swelling, itching, etc. There is also a possibility of mild systemic adverse reactions, such as vomiting, low fever, malaise, dizziness, etc. Most of these discomforts can disappear on their own and do not require treatment. After vaccination, take rest, eat a light diet and avoid overwork. Do not touch water or the vaccination site for a short period of time, and closely observe the change of body temperature and any discomfort.