title: Type-specific efficacy of acellular pertussis vaccine.
abstract: Two types of acellular pertussis vaccine have been used in Japan since their introduction in 1981. They are different in their antigen content and immunogenicity. To assess the type-specific efficacy of acellular pertussis vaccine commercially available in Japan, 442 households of patients with pertussis were surveyed from 1981 to 1987. The secondary attack rates in children 2 through 8 years of age were 61.3% (46/75) in unimmunized children, 7.5% (4/53) in children fully immunized by the filamentous hemagglutinin predominant type acellular pertussis vaccine, 14.3% (1/7) in children fully immunized by the pertussis toxin-filamentous hemagglutinin type vaccine, and 13.5% (7/52) in children given whole-cell pertussis vaccine. The estimated efficacy was 87.7% for the filamentous hemagglutinin predominant type vaccine and 76.7% for the pertussis toxin-filamentous hemagglutinin type vaccine in children aged 2 through 8 years. Both types of acellular pertussis vaccine were similarly effective, without any statistically significant differences, and their efficacy was not different from that of whole-cell vaccines. This survey also indicated that adults are a major source of infection, with a high secondary attack rate of 7.8%.
mesh_terms: D000328:Adult; D000942:Antigens, Bacterial / Q000276:immunology; D001886:Bordetella pertussis / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007564:Japan; D010567:Pertussis Vaccine / Q000276:immunology; D014917:Whooping Cough / Q000517:prevention & control* / Q000635:transmission
chemical_list: D000942:Antigens, Bacterial; D010567:Pertussis Vaccine