Antibody persistence against diphtheria, tetanus, pertussis, poliomyelitis and Haemophilus influenzae type b (Hib) in 5–6-year-old children after primary vaccination and first booster with a pentavalent combined acellular pertussis vaccine: immunogenicity and tolerance of a tetravalent combined acellular pertussis vaccine given as a second booster

The main objective of this study was to assess in 5–6-year-old French children ( n=234) the persistence of antibodies induced by a primary series vaccination (at 2–4 months of age) and a first booster (at 12–16 months of age) with a pentavalent two-component acellular pertussis combined vaccine (DTacP-IPV-Hib; Pentavac ®). The second objective was to evaluate in these 5–6-year-old French children the safety and the immunogenicity of a tetravalent acellular pertussis combined vaccine (DTacP-IPV; Tetravac ®) given as second booster. Results: Seroprotective antibody levels against diphtheria, tetanus, types 1–3 poliomyelitis and PRP were maintained 4–5 years after primary-vaccination and first booster with Pentavac ®. As expected, anti-PT antibodies levels were low, suggesting that children were not colonised by Bordetella pertussis. The second booster with Tetravac ® was well tolerated and elicited a strong booster response for all antigens. Conclusion: acellular pertussis combined vaccine, used in primary-vaccination, could be considered as having the same priming effect and the same efficacy as whole cell pertussis vaccine.