Bacteremic Pneumonia before and after Withdrawal of 13-Valent Pneumococcal Conjugate Vaccine from a Public Vaccination Program in Spain: A Case-Control Study.

OBJECTIVE: To compare the incidence and epidemiology of bacteremic community-acquired pneumonia (CAP) in the setting of changes in 13-valent pneumococcal conjugate vaccine (PCV13) coverage.

STUDY DESIGN: In the region of Madrid, universal immunization with the PCV13 started in May 2010. In July 2012, public funding ceased. Vaccination coverage decreased from >95% to 82% in 2013 and to 67% in 2014. We performed a multicenter surveillance and case-control study from 2009-2014. Cases were hospitalized children with bacteremic CAP. Controls were children selected 1:1 from next-admitted with negative blood cultures and typical, presumed bacterial CAP.

RESULTS: Annual incidence of bacteremic CAP declined from 7.9/100,000 children (95% CI 5.1-11.1) in 2009 to 2.1/100,000 children (95% CI 1.1-4.1) in 2012. In 2014, 2 years after PCV13 was withdrawn from the universal vaccination program, the incidence of bacteremic CAP increased to 5.4/100,000 children (95% CI 3.5-8.4). We enrolled 113 cases and 113 controls. Streptococcus pneumoniae caused most of bloodstream infections (78%). Empyema was associated with bacteremia (P = .003, OR 3.6; 95% CI 1.4-8.9). Simple parapneumonic effusion was not associated with bacteremia. Incomplete PCV immunization was not a risk factor for bacteremic pneumonia.

CONCLUSIONS: High rate of PCV13 immunization was associated with decreased incidence of bacteremic CAP; this incidence increased when rate of immunization fell. Empyema (but not parapneumonic pleural effusion) was associated with bacteremia.