We occasionally encounter older teens who received 4 doses of inactivated polio vaccine (IPV) before their fourth birthday. Should we recommend a 5th dose of IPV for these children?

CDC published a revised ACIP recommendation for IPV on August 6, 2009, to include a dose given at age 4 through 6 years (and at least 6 months after the preceding dose), regardless of the number of doses given before the fourth birthday. In general, you do not need to administer an additional IPV dose to older teens (or adults) who had already completed a routine 4-dose schedule of polio vaccination before their fourth birthday before the change was published in August 2009; however, if a dose given after the fourth birthday is needed for compliance with state requirements, you may want to check with your state immunization program or immunization registry manager to see what they accept/expect in this case. Contact information for state immunization managers can be found at www.immunize.org/coordinators.