REACTOGENICITY AND IMMUNOGENICITY OF A DOUBLE-STRENGTH ACELLULAR PERTUSSIS-VACCINE

The reactogenicity and immunogenicity of a double-strength acellular pertussis vaccine were evaluated after administration to 16 4-6-year-old children. The vaccine contained toxoided lymphocytosis-promoting factor (6.0-mu-g/dose), filamentous haemagglutinin (70-mu-g/dose), agglutinogens (1.4-mu-g/dose) and the 69 kDa protein (almost-equal-to 8.0-mu-g/dose). The vaccine was extremely well tolerated with few minor side effects following immunization. Significant increases in antibodies to all pertussis vaccine components were noted. In summary, this double-strength acellular pertussis vaccine, containing a very high dose of filamentous haemagglutinin, had minimal reactogenicity and was immunogenic. These findings, as well as other studies with this vaccine, indicate that filamentous haemagglutinin is not a major determinant of vaccine reactogenicity.