Article Text

Download PDFPDF
New combination vaccines still need a boost
  1. A J Pollard
  1. Correspondence to:
    Dr A J Pollard
    Department of Paediatrics, University of Oxford, Level 4, John Radcliffe Hospital, Oxford OX3 9DU, UK;andrew.pollard{at}

Statistics from

Perspective on the paper by Kitchin et al (see page 11)

Pertussis vaccination is part of the backbone of global immunisation policy because of the high rates of disease in unimmunised populations and a mortality in early infancy of about 1 in 500. Most of the world’s children are immunised with whole-cell pertussis vaccines, which were used in the UK from the 1950s and have been highly effective in reducing pertussis-related morbidity and mortality. Whole-cell pertussis vaccines contain >3000 pertussis proteins as a suspension of killed organisms, can cause severe local reactions, and are associated with inconsolable crying and hospitalisations related to febrile seizures or hypotonic hyporesponsive episodes (HHE) after immunisation in infants. By contrast, acellular pertussis vaccines, containing ⩽5 purified proteins (components) from Bordetella pertussis, are far less reactogenic than whole-cell pertussis vaccines. The decision to replace whole-cell pertussis vaccine in the UK schedule with Pediacel (DTaP–IPV–Hib; Sanofi Pasteur, Lyon, France) in 2004 was good news for infants, as it has an improved reactogenicity profile when compared with whole-cell pertussis vaccines,1 and can be expected to lead to a marked reduction in these unpleasant severe adverse events. A similar acellular pertussis vaccine, Pentacel (DTaP–IPV–Hib), also manufactured by Sanofi Pasteur, was shown to reduce HHE-related hospitalisations by 67% and febrile seizures by 79% after introduction in Canada in the late 1990s.2

The efficacy of new pertussis-containing vaccines is difficult to evaluate in immunised populations, and protection cannot be adequately assessed using immunogenicity measures alone, as serological correlates of protection are not clear.3 In addition to Pediacel, which contains five purified pertussis proteins, there are several other acellular pertussis vaccines available, with varying numbers of components and doses of proteins in them. Extrapolation from previous studies using similar vaccines is necessary in considering whether Pediacel might …

View Full Text


  • AJP acts as chief investigator for clinical trials conducted on behalf of Oxford University sponsored by vaccine manufacturers (Sanofi-Pasteur MSD, Novartis Vaccines, Glaxosmithkline Biologicals, Sanofi-Pasteur and Wyeth Vaccines), and has received assistance from manufacturers to attend scientific meetings. Industry-sourced consultancies and honoraria for lecturing or writing are paid directly to an independent charity or to an educational fund held by the Department of Paediatrics, University of Oxford. He is an inventor of patents in the area of MenB vaccines.

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

Linked Articles