Acellular Pertussis Vaccine Booster

The editors of Pediatrics have asked us to comment on the study by Pichichero et al,¹ because our report of booster vaccination with this vaccine, published in Pediatrics in 1989,² raised some questions with regard to the safety of the vaccine. The present study, with a design similar to ours, showed different and far more encouraging results: no serious systemic reactions; the same rate of local reactions as in our study but with no (or few) large local reactions in the group of children who received the acellular vaccine for both primary and booster vaccination; and better immunogenicity of the acellular booster in children who received the acellular vaccine only than in the children who received whole-cell vaccine for their primary series (in contrast to the opposite result in our study).