REACTOGENICITY AND IMMUNOGENICITY OF A 3- COMPONENT ACELLULAR PERTUSSIS DTPA VACCINE COMPARED TO THE CONVENTIONAL WHOLE-CELL DTPG VACCINE -RESULT OF A DOUBLE-BLIND RANDOMIZED MULTICENTER STUDY

Target: Evaluation of reactogenicity and immunogenicity of an acellula r, three-component pertussis vaccine (DTPa) in infants compared to the conventional whole-cell vaccine (DTP). Method: Multicentre, randomise d double-blind study in non-immunised infants. In 23 centres a total o f 589 children aged from 10 to 32 weeks were enrolled and vaccinated w ith three doses of the study vaccine. The acellular vaccine contained three defined pertussis antigens pertussis toxin (PT), filamentous hae magglutinin (FHA) and 69 kDa OMP (pertactin). In addition, both types of vaccine contained diphtheria and tetanus toroid in usual concentrat ions. The reactogenicity was recorded by using standardised diary card s. The immunogenicity was determined by measuring the anti-PT, anti-FH A and anti-69 kDa antibodies before and after primary vaccination. Res ults: The frequency of local and systemic adverse reactions was signif icantly lower in the children with acellular vaccine than in the child ren with whole-cell vaccine. This also became evident from the signifi cant lower prescription of drugs, especially of antipyretics and analg etics, during the observation period. At the same time the acellular v accine was clearly more immunogenic than the conventional vaccine. No differences in reactogenicity and immunogenicity could be observed amo ng the three lots of acellular vaccine that were used. Conclusion: The acellular three-component vaccine is very suitable for primary vaccin ation in infants because of the low reactogenicity, the high immunogen icity and the recently shown clinical efficacy.