TOWARDS BETTER PERTUSSIS VACCINES

Several recently completed trials have shown that acellular pertussis vaccines induce substantial protection against pertussis. They are con siderably less reactogenic than whole-cell vaccines and, as they consi st of only one or a few purified proteins, they can be expected to cau se less severe adverse events. The optimal composition of acellular va ccines has not yet been determined. The number of vaccine antigens var ies from one to five. All vaccines contain detoxified pertussis toxin. Other antigens included in several vaccines are filamentous haemagglu tinin, pertactin and fimbriae, but it remains to be proven that these antigens contribute significantly to protection. Postlicensure studies will be of importance in order to study possible rare adverse events after acellular vaccines and to study the induction of herd immunity.