Antistofresponserne til booster- doserne hos småbørn efter en serie bestående af to eller tre doser var imidlertid sammenlignelige for alle 7 vaccineserotyper, og dette indikerede, at begge spædbørnsregimener fremkaldte en tilstrækkelig priming.
However, antibody responses to booster doses in toddlers following two-dose or three-dose infant series were comparable for all 7 vaccine serotypes and indicated that both infant regimens had elicited adequate priming.