Invasive pneumococcal disease (IPD) remains an important cause of illness in US children. We assessed the impact of introduction of the 13-valent pneumococcal conjugate vaccine (PCV13) on pediatric IPD rates, as well as changes in racial and regional differences in IPD, in Tennessee.
Data from active laboratory and population-based surveillance of IPD were used to compare IPD rates in the early-PCV7 (2001–2004), late-PCV7 (2005–2009), and post-PCV13 (2011–2012) eras. IPD rates were further stratified according to age, race, and region (east and middle-west TN).
Among children aged <2 years, IPD rates declined by 70% from 67 to 19 per 100 000 person-years in the early-PCV7 era and post-PCV13 era, respectively. Similar decreasing trends in IPD rates were observed in older children aged 2 to 4 years and 5 to 17 years. In the late-PCV7 era, IPD rates in children aged <2 years were higher in black children compared with white children (70 vs 43 per 100 000 person-years); however, these racial differences in IPD rates were no longer significant after PCV13 introduction. Before PCV13, IPD rates in children aged <2 years were also higher in east Tennessee compared with middle-west Tennessee (91 vs 45 per 100 000 person-years), but these differences were no longer significant in the post-PCV13 era.
PCV13 introduction led to substantial declines in childhood IPD rates and was associated with reduced regional and racial differences in IPD rates in Tennessee.