Background. The recently-recommended change to a sequential schedule of inactivated polio vaccine (IPV) followed by oral poliovirus vaccine (OPV) requires an additional injection. Surveys of parental attitudes have identified reticence toward an extra injection, but little information is available on actual parental choice in this situation. Objective. Determine the proportion of children receiving IPV, OPV and other concurrent immunizations. Setting. Six public health clinics. Interventions. Beginning July 1996, providers informed parents of the three polio vaccination options, recommending the IPV/OPV sequential schedule. Results. Of 1588 infants < 4 months of age presenting for their first polio immunization, 1167 (73%) received IPV and 421 (27%) OPV. The children receiving IPV1 were less likely to be white (29% vs 37%, p<.001) and more likely to be enrolled in WIC (84% vs 76%, p<.001). Children receiving IPV1 were as well vaccinated as those receiving OPV for DTP(99.6 vs 100%), Hib (99.7 vs 100%), and were more likely to be up-to-date for their second dose of Hepatitis B (81.5 vs 67.9%, p<.001). In the six months prior to initiation of the sequential schedule, 577 (99%) of infants < 4 months of age received OPV1 and 6 (1%) received IPV1. During the same period the following year, 69 (12.5%) of infants < 4 months of age received OPV1 and 483 (87.5%) received IPV1. In this group, children receiving IPV were more likely to return for their second dose than those receiving OPV (77 vs 65%, p=.03). Acceptance of IPV increased even further in the following six month period, with 95% of infants < 4 months of age receiving IPV1 and 5% receiving OPV1. Conclusions. The need for additional injections to initiate the sequential or all IPV poliovirus vaccination options has not impeded parental acceptance of recommended vaccines. In the context of parental choice and a provider recommendation, most parents chose IPV. In addition, children receiving IPV remain up-to-date for polio and other vaccines.
