SUMMARY Background In 2000, 7-valent pneumococcal conjugate vaccine (PCV7) was introduced in the U.S. and resulted in dramatic reductions in invasive pneumococcal disease (IPD) and modest increases in non-PCV7-type IPD. In 2010, a 13-valent pneumococcal conjugate vaccine (PCV13) replaced PCV7 in the U.S. immunization schedule. We evaluated the effect of PCV13 use in children on IPD in children and adults in the U.S. Methods We used laboratory- and population-based data on incidence of IPD from CDC’s Emerging Infections Program / Active Bacterial Core surveillance in a time-series model to estimate the impact of vaccination. Cases of IPD during July 2004–June 2013 were classified as being caused by the PCV13 serotypes against which PCV7 has no effect (PCV13/nonPCV7). Findings Compared with incidence expected among children <5 years old if PCV7 alone had been continued, incidence of IPD overall and IPD caused by PCV13/nonPCV7 serotypes declined by 64% (95% interval estimate [IE] 59–68 %) and 93% (95%IE 91–94), respectively, by July 2012–June 2013. Among adults, incidence of IPD overall and PCV13/nonPCV7-type IPD also declined by 12–32% and 58–72%, respectively, depending on age. In all age groups, reductions were driven principally by changes in incidence of serotypes 19A and 7F. We estimate that over 30,000 cases of IPD and 3,000 deaths were averted in the first 3 years following PCV13 introduction. Interpretation PCV13 has reduced IPD among all ages when used routinely in children in the U.S. Serotypes 19A and 7F, which emerged after PCV7 introduction, have been effectively controlled.

Background Sepsis in the first 3 days of life is a leading cause of morbidity and mortality among infants. Group B Streptococcus (GBS), historically the primary cause of early-onset sepsis, has declined through widespread use of intrapartum chemoprophylaxis. We estimated the national burden of invasive early-onset sepsis (EOS) cases and deaths in the era of GBS prevention. Methods Population-based surveillance for invasive EOS was conducted in 4 of CDC’s Active Bacterial Core surveillance (ABCs) sites from 2005–2008. We calculated incidence using state and national live birth files. Estimates of the national number of cases and deaths were calculated, standardizing by race and gestational age. Results ABCs identified 658 cases of EOS; 72 (10.9%) were fatal. Overall incidence remained stable during the three years (2005:0.77 cases/1,000 live births; 2008:0.76 cases/1,000 live births). GBS (~38%) was the most commonly reported pathogen followed by Escherichia coli (~24%). Black preterm infants had the highest incidence (5.14 cases/1,000 live births) and case fatality (24.4%). Non-black term infants had the lowest incidence (0.40 cases/1,000 live births) and case fatality (1.6%). The estimated national annual burden of EOS was approximately 3,320 cases (95% CI: 3,060–3,580) including 390 deaths (95% CI: 300–490). Among preterm infants, 1,570 cases (95% CI: 1,400–1,770; 47.3% of the overall) and 360 deaths (95% CI: 280–460; 92.3% of the overall) occurred annually. Conclusions The burden of invasive early-onset sepsis remains substantial in the era of GBS prevention and disproportionately affects preterm and black infants. Identification of strategies to prevent preterm births is needed to reduce the neonatal sepsis burden.

GBS prevention efforts have not led to an increasing burden of early-onset E coli infections. However, the stable burden of E coli sepsis and associated mortality underscore the need for interventions.