From whole cell to acellular pertussis vaccines

Abstract

It is likely that within the next few years information derived from ongoing pertussis vaccine efficacy trials will result in the introduction of an acellular pertussis vaccine (ACV) that is equally effective in preventing disease as the current whole-cell vaccines (WCVs). The impetus to develop new pertussis vaccines was to diminish the side-effects caused by the WCVs. Results obtained so far clearly indicate that the ACVs are successful in this respect. Apart from the occurrence of side effects, another important shortcoming of the WCVs is their low level of protection against infection. Experience with Japanese ACVs indicate that in this respect ACVs will probably not show a significant improvement. Finally, a point of concern is the effectiveness of ACVs against Bordetella parapertussis. There is evidence that ACVs may protect less well against B. parapertussis than the WCVs. Thus, introduction of ACVs may lead to an increase in the incidence of B. parapertussis infections.