If you have received the AC vaccine, you can also receive the quadrivalent vaccine. The AC vaccine belongs to a class of vaccines required by the state and is usually provided free of charge by the state. The AC vaccine is effective in preventing epidemic meningitis caused by type A and type C bacteria, provided that the child is in good health and receives the vaccine in a timely manner. The Quadrivalent Meningitis Vaccine (QMV) contains A, C, Y and W135 types of meningitis and is able to prevent a wider range of epidemic meningitis caused by the four types of bacteria mentioned above. Quadrivalent meningitis vaccine is a Class II vaccine and requires self-payment. At present, more than 85% of epidemic meningitis caused by type A and type C bacteria in clinical practice, i.e. the AC influenza vaccine can play an effective preventive role. However, if you want more comprehensive prevention, you can also be vaccinated when conditions permit. If you feel unwell after vaccination, you should go to the hospital in time and get treatment under the guidance of the doctor, and you can decide whether to get vaccinated by consulting the professional doctors of the local medical institutions.