THE EFFICACY OF A WHOLE-CELL PERTUSSIS-VACCINE AND FIMBRIAE AGAINST BORDETELLA-PERTUSSIS AND BORDETELLA-PARAPERTUSSIS INFECTIONS IN A RESPIRATORY MOUSE MODEL

Due to local and systemic side-effects, the currently used, highly eff ective, whole-cell pertussis vaccines (WCVs) will be replaced by acell ular vaccines (ACVs) in some countries. These ACVs contain detoxified pertussis toxin, either alone or in combination with the filamentous h aemagglutinin, pertactin and fimbriae. Ongoing clinical trials show th at ACVs are clearly less reactogenic than WCVs, and that ACVs comprise d of three to five proteins are highly efficacious in inducing protect ion against Bordetella pertussis infections. An important unresolved q uestion is, what the effect will be of the switch from WCVs to ACVs on the incidence of Bordetella parapertussis infections, the second caus ative agent of pertussis. A comparison of the efficacy of WCVs and ACV s against B. parapertussis infection in a murine respiratory model, al though less efficiently than against B. pertussis infection. It was sh own previously that the ACV components pertussis toxin, FHA and pertac tin did not protect against B. parapertussis infection in a murine res piratory model. We have investigated the efficacy of two other ACV com ponents, B. pertussis serotype-2 and -3 fimbriae against B. parapertus sis infection in the murine model. The B. pertussis fimbriae protected mice against B. parapertussis infection although less efficiently tha n against B. pertussis infection. This result indicates that B. pertus sis and B. parapertussis fimbriae are antigenically distinct. B. pertu ssis fimbriae were found to be as efficacious as the WCV against B. pe rtussis infection. Our results are discussed in the light of the switc h from WCVs to ACVs. (C) 1998 Elsevier Science Ltd. All rights reserve d.