Cases of invasive pneumococcal disease in children reduced

The number of cases of invasive pneumococcal disease (IPD) in children has fallen since the introduction of a new vaccine a year ago. Enhanced surveillance by the UK's Health Protection Agency has shown that cases of IPD caused by the seven major types of the pneumococcus bacteria which the new pneumococcal conjugate vaccine (PCV) protects against have gone down by almost 50%.

Infections caused by the pneumococcus bacteria are a leading cause of serious illness, for example meningitis and pneumonia, in children in the UK . Currently there are more than 90 known pneumococcal types and the PCV vaccine protects against the seven most common types which circulate in the UK .

HPA scientists followed up on the 409 cases of IPD in children in England and Wales since the vaccine was introduced in September 2006, to monitor the vaccine's impact. The team reviewed patient blood samples and worked closely with GPs and paediatricians to determine immunisation histories of patients.

The team estimates that around 170 cases were prevented by the vaccine and the remaining cases they investigated were a mixture of those who were either not yet immunised, had not received a full course appropriate for their age group, or were infected with a type that was not in the vaccine.

In September 2006 the vaccine was introduced into the routine childhood immunisation programme at two, four and thirteen months of age with a catch-up campaign to two years of age to protect children from pneumococcal infection. The HPA was asked to measure its impact on reducing the infection in children.

Pauline Kaye, who is presenting the research at the HPA conference said, “IPD is one of the leading causes of serious illness in young children in the UK. Our monitoring of the infection since the introduction of an effective vaccine has shown that it provides good protection against the main types of the pneumococcus bacteria.

Our early evaluation of the vaccine also shows that it provides good protection of around 84% in children following two doses in infants and 75% protection after a single dose.”

Professor Pat Troop, Chief Executive of the HPA said, “This work, undertaken in close collaboration with colleagues throughout the NHS underlines the importance of HPA surveillance in assessing the impact of vaccination programmes and thus contributes significantly to protecting the health of our children and the wider population”.