The HFMD vaccine, as a common vaccine, is actually not very safe in terms of side effects. After the HFMD vaccine is administered, adverse reactions may occur, such as fever, rash, irritability, and other such conditions. Fever is one of the more common cases, but the degree of fever is generally lower, the duration is also relatively short, the fever caused by vaccination usually does not exceed 38.5 ℃, the duration is generally not more than 24 hours, and most of them will soon be relieved. However, in rare cases, the fever may last up to 48 hours, but although the child has a fever, the child’s mental state and diet are all very good, and only need to give simple symptomatic treatment, the child’s fever symptoms or symptoms of irritability will soon be relieved.