The third dose of vaccine refers to the third vaccine of the new crown vaccine, and it is necessary to decide whether to make an appointment or not according to the local situation. If the vaccine is not in short supply, you don’t need to make an appointment and can go directly to the vaccine, but if the vaccine is in short supply, you need to make an appointment earlier. You can call your local community vaccination department in advance for advice. Vaccination is an effective measure to prevent certain infectious diseases, but we should pay attention to safety, some people can have adverse reactions to vaccination, such as fever, headache, weakness, vomiting and dizziness and other adverse reactions. People with allergies should be cautious about vaccinations. Vaccination is prohibited in the presence of acute illness, acute attacks of chronic diseases, pregnant women and people who are allergic to vaccines. Make an appointment for vaccination or go directly for vaccination, and if you become unwell after vaccination, you should contact your doctor in time and, depending on the situation, treat it according to the norms.