Inactivated poliovirus vaccine alone or sequential inactivated and oral poliovirus vaccine in two-, four- and six-month-old infants with combination Haemophilus influenzae type B/hepatitis B vaccine

Background. Advisory committees have recommended the increased use of inactivated poliovirus vaccine (IPV) for children. Objectives. The purpose of this study was to assess the safety and immunogenicity of three schedules using IPV administered with diphtheria and tetanus toxoids and whole cell pertussis vaccines in a dual-chambered syringe. Children also received a combination of Hacmophilus influenzae type b (Hib) and hepatitis B vaccines (COMVAX(TM)). Methods. All infants (n = 295) received IPV and COMVAX(TM) at 2 and 4 months of age and IPV, oral poliovirus vaccine (OPV) or both vaccines at 6 months and OPV at 15 months of age. Results. After two doses of IPV 96 to 100% of infants had antibodies to poliomyelitis viruses types 1, 2 and 3, and after a third dose of vaccine (IPV or OPV) all but one child had antibodies to all three poliovirus types. After two doses of COMVAX(TM) 89 and 96% of children had protective levels of antibody to Hib and hepatitis B, respectively. Conclusions. IPV is highly immunogenic in a two-dose schedule. Administration of a thirddose of IPV or a dose of OPV at 6 months of age is highly effective. Simultaneous administration of a combination H. influenzae type b/hepatitis B vaccine did not interfere with the response to IPV.