Racial disparities in invasive streptococcus pneumoniae infections, 1998-2009

Abstract

Background. Before the introduction of 7-valent pneumococcal conjugate vaccine (PCV7), invasive pneumococcal disease (IPD) rates among blacks were twice the rates in whites. We measured the effects of trends in PCV7-type and non-PCV7-type IPD rates on racial disparities in overall IPD and estimated the proportion of IPD caused by serotypes included in the 13-valent pneumococcal conjugate vaccine (PCV13).Methods. We analyzed data from the Active Bacterial Core surveillance system, which performs active, laboratory- and population-based surveillance for IPD for 29.2 million people in the United States, for the period 1998-2009. For patients with unknown race, we multiplied imputed race to calculate age-, race-, and serotype-specific IPD incidence rates.Results. During 1998-2009, 47 449 IPD cases were identified; race was unknown for 5419 (11%). After multiple imputation, 31 981 (67%) patients were considered white and 13 750 (29%) black. PCV7-type IPD rates in all ages in both races decreased to <1 case per 100 000, whereas there were no decreases in overall IPD rates after 2002. By 2009, PCV13 serotypes caused 71% of cases among whites aged <5 years compared with 58% among blacks (P