Incidence of paediatric pneumococcal meningitis and emergence of new serotypes: a time-series analysis of a 16-year French national survey

Summary Background Successive implementation of seven-valent then 13-valent pneumococcal conjugate vaccines (PCVs) led to a marked decrease in pneumococcal disease burden, including pneumococcal meningitis. We assessed the long-term effect of implementation of PCVs on incidence of pneumococcal meningitis in children in France over a 16-year period. Methods We did a quasi-experimental, population-based interrupted time-series analysis with a nationwide prospective survey over 16 years in France, recruiting children aged younger than 15 years from 227 paediatric wards from January, 2001, to December, 2016. The main outcome by the time-series model was the estimated incidence of pneumococcal meningitis per 100?000 children (of a population of 12·6 million children in 2017) before and after PCV7 and PCV13 implementation. The time-series model was based on segmented regression with autoregressive error. Findings We enrolled 1778 children with pneumococcal meningitis. PCV13 implementation led to a significant reduction in monthly incidence of pneumococcal meningitis from 0·12 per 100?000 children before PCV13 to a nadir of 0·07 in December, 2014 (?38%, 95% CI ?56·1 to ?20·4;