ABSTRACT. A change in the recommendations for routine immunization of children is indicated because of the reduced risk of exposure to wild-type polio viruses and the continued occurrence of vaccine-associated paralytic poliomyelitis after oral polio vaccine (OPV). All children should receive four doses of vaccine before the child enters school. Regimens of sequential inactivated polio vaccine (IPV) and OPV, IPV only, or OPV only are acceptable. Each regimen has advantages and disadvantages. In special circumstances, one of the regimens is preferred or recommended. Because logistical problems with the current childhood immunization schedule may make these new recommendations difficult to implement immediately, their adoption likely will be gradual. Nevertheless, assuming continued progress toward global eradication and the development of new combination products, the routine use of an IPV-only regimen is likely to become desirable and feasible in future years.
VACCINE EFFECTIVENESSSince the introduction of poliovirus vaccines in the 1950s and early 1960s, their effectiveness in the prevention of poliomyelitis has been amply demonstrated. The last reported case in the United States of indigenously acquired poliomyelitis caused by wild poliovirus was in 1979.1 No cases have occurred in the western hemisphere since August 1991.2 These and other findings from national surveillance in countries of the Americas led to the certification in 1994 by an international commission that wild-type poliovirus transmission has been interrupted in this hemisphere, thus achieving a goal established by the Pan American Health Organization in 1985.3 Concurrently, the global poliomyelitis eradication initiative of the World Health Organization (WHO) has resulted in a more than 80% reduction in the incidence of reported poliomyelitis cases worldwide since 1988 and demonstrated that the goal of global eradication is achievable. 4,5 These successes are attributable primarily to the widespread use of oral polio vaccine (OPV), which is the vaccine recommended by the WHO. Continued progress in poliomyelitis elimination clearly necessitates the use of OPV in those countries in which wild poliovirus remains or recently has been endemic. In the United States, the Advisory Committee on Immunization Practices (ACIP) of the Centers for Disease Control and Prevention (CDC) has strongly reaffirmed its support of the eradication program and the use of OPV for this purpose.
6In the United States, the evolving national and international epidemiology of poliomyelitis in the past two decades has prompted reexamination of current vaccination recommendations for the routine use of OPV. Earlier reevaluation by the Institute of Medicine in 1977 and again in 1988 had reaffirmed the use of OPV for national poliomyelitis control at those times. 7,8 Since 1979, however, nearly all cases of paralytic poliomyelitis in the United States have been vaccine associated.Between 1980 and 1994, a total of 125 cases of vaccine-associated paralytic poliomyelitis (VAPP) we...