IMMUNOGENICITY AND SAFETY OF A MONOVALENT, MULTICOMPONENT ACELLULAR PERTUSSIS-VACCINE IN 15-MONTH 6-YEAR-OLD GERMAN CHILDREN

Immunization against pertussis has been re-recommended for healthy chi ldren in Germany in 1991. In addition the former restriction of immuni zing only in the first 2 years of life was abolished. In children born before 1991 immunization rates against pertussis were 15% or less. Wi th the new recommendations physicians are now faced with an increasing demand of parents for catch-up vaccinations in these children. Since they were immunized against diphtheria and tetanus previously monovale nt pertussis vaccines are needed for this indication. Therefore a mono valent, multicomponent acellular pertussis vaccine was studied in 249 German children 15 months to 6 years of age. Three doses were administ ered at 6-10 week intervals. Reactogenicity and antibody responses aga inst the vaccine antigens pertussis toxin (PT), filamentous haemagglut inin (FHA), 69-kd antigen (pertactin) and fimbriae-2 (agglutinogen) we re investigated. Local and systemic reactions were minimal in frequenc y and severity. Antibody responses against all vaccine antigens were p ronounced with 93%-100% of vaccinees demonstrating at least four fold titre rises above pre-immunization after the third dose. These finding s indicate that this monovalent, multicomponent acellular pertussis va ccine with excellent immunogenicity and low reactogenicity is an appro priate candidate for closing immunization gaps in older children in co untries with previously low vaccination rates against pertussis. Based on the results of this study the monovalent acellular pertussis vacci ne was licensed in Germany in January 1994.