Localized redness and swelling can occur after Pentavalent vaccine injection, which may be a normal reaction to the vaccination, or it may be caused by infection or cellulitis. You can use iodophor disinfection, application of drugs and other treatments 1. Normal reaction after vaccination: Pentavalent vaccine is an inactivated vaccine, which will cause local reaction after contact. Usually it will disappear after 2~3 days. If there is redness and swelling, local care is needed, and iodophor can be used to disinfect to avoid infection. 2. Infection: after vaccination, there will be local itching, scratching the local area with hands will lead to local bacterial infection, resulting in skin ulceration. At this time, we should pay attention to the hygiene of hands and local cleanliness, can use mupirocin for anti-infection. When the infection is serious caused by the local cellulitis, this time the redness and swelling is obvious and the pain is serious, you can use topical medication under the guidance of the doctor available 25% ~ 50% magnesium sulfate, antibiotics (such as amoxicillin, etc.), and if necessary, surgical treatment. If the baby has the above situation, persistent unrelieved, to consult the doctor in time, give timely diagnosis and treatment.