Polio vaccination schedules in the United States: The rationale for change

Guidelines for polio immunization have undergone some major changes in the past few years after remaining almost unaltered for about three decades. The most recent of these changes occurred in 1999, when the Advisory Committee on Immunization Practices (ACIP), the American Academy of Pediatrics (AAP), and the American Academy of Family Physicians (AAFP) recommended the inactivated poliovirus vaccine (IPV) for the first two doses of poliovirus vaccine for routine childhood immunization. The oral poliovirus vaccine (OPV) no longer is recommended for the first two doses and is acceptable only when parents refuse the extra injections needed to administer IPV, when travel is imminent to countries where polio is endemic, or during an outbreak of wild-type poliovirus infection. The shift away from OPV and an increasing preference for IPV was brought about by the progress that has occurred in global eradication of poliomyelitis and by the need for a further reduction in the incidence of vaccine-associated paralytic poliomyeletis (VAPP) that has been associated with OPV. This review will discuss the history of poliomyelitis in the United States, the development of OPV and IPV, the epidemiology of VAPP, the risks and benefits of all the proposed vaccination options, and practical approaches to implementing the new guidelines.