Abstract
Current guidelines recommend up to two doses of the pneumococcal conjugate heptavalent vaccine (PCV-7) in children up to 5 years old followed by and a dose of the polysaccharide vaccine (PPV-23) for patients over 2 years old to broaden serotype immunity. We assessed the serotype responses to two doses of PCV-7 and a dose of PPV-23 in a cohort of children in the 2-16-year age range in order to determine whether PPV-23 induced effective immunity to non-PCV-7 serotypes. Pneumococcal antibody concentrations to the seven serotypes covered by PCV-7 and five additional serotypes covered by PPV-23 but not PCV-7 were measured in 60 children aged 2-16 years. None of the children had a primary antibody immunodeficiency. Vaccinated children had 7-30-fold higher antibody concentrations than unvaccinated children to all serotypes contained in the PCV-7 (P < 0.001). In contrast, serotypes covered by the PPV-23 but not PCV-7 were only one- to two-fold higher and there was no significant increase in the number of children who had protective concentrations of antibody (≥0.35 mcg/ml) against these serotypes. In this cohort of children, PPV-23 vaccine did not broaden the protection in vitro against potentially pathogenic strains of Streptococcus pneumoniae. We call into question the recommendation to use the PPV-23 in children.
Original language | English |
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Pages (from-to) | 6321-6325 |
Number of pages | 5 |
Journal | Vaccine |
Volume | 25 |
Issue number | 34 |
DOIs | |
Publication status | Published - 21 Aug 2007 |
Bibliographical note
Funding Information:Conflict of interest statement : Dr. Balmer has received assistance to attend scientific meetings from Wyeth Vaccines, Baxter Bioscience and Chiron Vaccines. Industry honoraria received for lecturing are paid directly into Central Manchester and Manchester Children's University Hospitals NHS Trust endowment fund. Dr. Borrow has received assistance to attend scientific meetings from Wyeth Vaccines and Baxter Bioscience and has served as a consultant for GlaxoSmithKline, Fujisawa GmbH, Sanofi Pasteur and Baxter Bioscience. Industry honoraria received for consulting, lecturing and writing are paid directly into Central Manchester and Manchester Children's University Hospitals NHS Trust endowment fund. Dr. Borrow has performed contract research on behalf of the Health Protection Agency (funded by Wyeth Vaccines, Chiron Vaccines, Baxter Bioscience, GlaxoSmithKline, Sanofi Pasteur, Fujisawa GmbH, Alexion Pharmaceuticals Inc., Microscience Ltd. and Xenova Research Ltd. Dr. Arkwright declares no conflicts of interest.
Keywords
- Children
- Pneumococcal antibodies
- Serotypes
- Streptococcus pneumoniae
- Vaccine