Do we need an extra dose of a meningococcal vaccine in adolescence?
Professor Andrew Pollard and Dr Matthew Snape answer:
It is now almost 11 years since the introduction of the serogroup C meningococcal (MenC) vaccine into the UK in 1999, and the huge impact of this vaccine has been sustained throughout the last decade so that there were only a handful of cases in 2009. A crucial component of the success of the vaccine introduction was the ‘catch-up’ campaign that aimed to immunise everyone under the age of 19 years. The rates of disease were reduced among adolescents (previously a time of increased risk for MenC disease) as a direct effect of the vaccine, but the vaccine also prevented these teenagers inadvertently spreading the bacteria from their nose or throat to younger children or unimmunised adults, adding to the value of the vaccine by reducing the risk of disease for these groups too.
It now appears from these observations that maintaining high levels of immunity among adolescents and young adults may be important, even critical, to keep MenC disease under control since it protects the rest of the population. However, from studies conducted by the Oxford Vaccine Group and the Health Protection Agency, it has been shown that immunity falls rapidly after immunisation in early childhood and the majority of children entering adolescence over the next decade, who got their dose in the original MenC campaign, will not have protective levels of MenC antibody.
Do we need to introduce an extra dose of a meningococcal vaccine in early adolescence to maintain both direct protection in this age group and provide the broader community protection? Although there is no rush to introduce a booster today as we have so little MenC disease activity, investigation of the role of an adolescent booster is important in the near future assuming the vaccine were needed for those immunised in the 1999 campaign before they leave school. The good news is that, unlike the situation in early childhood, protection does appear to persist for years when the vaccine is given to adolescents.
Intriguingly, an adolescent booster could be an opportunity to provide broader protection against meningitis and septicaemia if we decided to use the newly licensed MenACYW vaccine (covers meningococcal serogroups A, C, W-135 and Y) instead of the MenC vaccine that is used today. Indeed, this is the approach that has already been taken in Canada, where a booster dose of meningococcal vaccine was recently recommended for 12 year olds.
This is an unfolding chapter in the battle against meningitis and septicaemia but for once we may be ahead of the game.
is Professor of Paediatric Infection and Immunity at the University of Oxford, Director of the Oxford Vaccine Group, and Honorary Consultant Paediatrician at the Children’s Hospital there.
He chairs the UK’s NICE meningitis guideline development committee. His current research includes clinical trials of new and improved vaccines for children, development of a serogroup B meningococcal vaccine, bacterial diseases in children in Nepal, and studies of immune responses to vaccines. He has published over 200 articles and books. He has recently joined MRF’s Scientific Advisory Panel.
Matthew Snape is a Consultant in Vaccinology at the Oxford Vaccine Group, University of Oxford, and a Consultant in General Paediatrics at Oxford Radcliffe Hospital NHS Trust. His research includes clinical trials of vaccines against meningococcal and pneumococcal disease, and with a particular interest in the immunisation of adolescents against meningococcal disease.