Impact of 10-and 13-valent pneumococcal conjugate vaccines on incidence of invasive pneumococcal disease in children aged under 16 years in Germany, 2009 to 2012

We assessed the impact of 10-valent and 13-valent pneumococcal vaccines (PCV10 and PCV13), which were introduced in Germany in 2009, on the incidence of meningitis and non-meningitis invasive pneumococcal disease (IPD) in children aged under 16 years in a population previously vaccinated with a sevenvalent vaccine (PCV7). Surveillance of IPD (isolation of Streptococcus pneumonia from a normally sterile body site) is based on data from two independent reporting sources: hospitals and laboratories. IPD incidence was estimated by capture-recapture analysis. Incidence rate ratios (IRRs) were calculated for 2009 and 2012, thus comparing pre-and post-PCV10 and PCV13 data. IPD incidence caused by serotypes included in PCV13 decreased in all age and diagnosis groups. A rise in non-vaccine serotype incidence was seen only in children aged under two years. The overall impact varied by age group and infection site: for meningitis IPD in children aged under 2, 2-4 and 5-15 years, incidence changed by 3% (95% CI: -31 to 52), -60% (95% CI: -81 to -17) and -9% (95% CI: -46 to 53), respectively. A more pronounced incidence reduction was observed for non-meningitis IPD: -30% (95% CI: -46 to -7), -39% (95% CI: -54 to -20) and -83% (95% CI: -89 to -73) in children aged under 2, 2-4 and 5-15 years, respectively. A higher tropism of the additional serotypes for non-meningitis IPD may be a potential explanation. The heterogeneous findings emphasise the need for rigorous surveillance