The HFMD vaccine expiration date cannot be generalized and may be more than 2 years. HFMD is mainly caused by enterovirus 71 and coxsackievirus A16, but can also be caused by a variety of other enteroviruses. Currently, there is only a vaccine for enterovirus 71 in China, and there is no exact data on its expiration date. Some studies have shown that after 2 years of vaccination, there is still a high concentration of antibodies in the body, so it is estimated that it can be valid for 2-3 years. Although HFMD vaccination can effectively reduce the incidence of HFMD, the vaccine is only effective in preventing HFMD caused by enterovirus 71, so the vaccination is not permanent and there is still a possibility of getting sick. HFMD mainly occurs in children under 5 years of age, and the vaccination period is between 6 months and 36 months of age, and two doses are required, with an interval of 1 month between doses.