Polio vaccine generally refers to the polio vaccine, which prevents poliovirus infection and thus prevents poliomyelitis. The number of polio vaccinations depends on the type of vaccine, and the main types of polio vaccines include injectable polio vaccine and oral polio vaccine, with different vaccination schedules for different types of polio vaccines. 1. Injectable polio vaccine: Injectable polio vaccine, i.e., inactivated polio vaccine, is a type II vaccine and requires self-payment. There are five doses in total. The first dose of inactivated polio vaccine is usually given at 2 months of age, the second dose at 4 months of age, the third dose at 6 months of age, the fourth dose at 15-18 months of age, and a booster dose at 4-6 years of age. Children with low immunity are usually recommended to receive the inactivated polio vaccine by injection, which usually does not cause serious adverse reactions in children because the virus is inactivated. 2. Oral polio vaccine: The oral polio vaccine, known as live attenuated polio vaccine, is a white solid sugar pill that is administered orally and is usually given four times. The routine vaccination schedule is the first vaccination at 2 months of age, the second at 3 months of age, the third at 4 months of age, and the fourth at 4 weeks of age. The live attenuated polio vaccine should not be eaten within half an hour before and after the vaccination. Oral administration of live attenuated polio vaccine is usually not recommended for vaccinated children with low immunity, who often have colds, fevers, pneumonia or diarrhea, or who have prolonged perianal abscesses; such live attenuated vaccines may pose a risk for children with low immunity. There is also a five-dose vaccine available on the market, and children can also choose to receive the five-dose vaccine because it contains polio vaccine, diphtheria vaccine, pertussis vaccine, diphtheria vaccine, tetanus vaccine, and Haemophilus influenzae type B conjugate vaccine. Whether injected or given orally, children should be kept under observation for half an hour after polio vaccine administration to observe for adverse reactions. Common adverse reactions after polio vaccination include mild fever, nausea, vomiting, diarrhea, rash, etc. They generally do not require special treatment and may gradually resolve or disappear after a few days, with symptomatic treatment if necessary. Children are not recommended to take a bath within 24 hours after vaccination, and it is recommended to follow the medical advice and vaccination schedule.