HIB vaccine can prevent Haemophilus influenzae type B infection, which can cause meningitis, pneumonia, sepsis, and arthritis in infants and children. Therefore, HIB vaccination is more helpful in preventing diseases in infants and young children. When infants are vaccinated with HIB vaccine, they are divided into the following cases: 1. starting before 6 months of age: HIB vaccine can be given as early as 2 months of age, with a total of three doses for the first vaccination, at an interval of 1-2 months, and a booster shot at 1.5 years of age; 2. starting at 6-12 months of age: two doses are needed for the first vaccination, at an interval of 1-2 months, and a booster shot at 1.5 years of age; 3. not vaccinated over 1 year of age: only HIB vaccine is a relatively safe vaccine, and adverse reactions are rare. A few infants and children may experience slight redness, swelling, pain, or mild fever, loss of appetite, restlessness, vomiting, diarrhea and abnormal crying in the injection area within 48 hours after vaccination, which generally do not require special treatment. If the above situation is serious or lasts for more than 24 hours, or if allergic reactions such as rash or wheezing occur, the patient should be sent to the hospital immediately for treatment.