Pneumococcal Pneumonia Requiring Hospitalization in US Children in the 13-Valent Pneumococcal Conjugate Vaccine Era

Abstract

Background. The incidence of complicated pediatric pneumococcal pneumonia (PP) increased in the late 2000s. Few data exist on the impact of PCV13 on PP in children. We compared the serotype (ST) distribution, antibiotic susceptibility and outcomes of children with PP 4 yrs before and 4 yrs after the introduction of PCV13. Methods. We identified patients ≤18 years with PP at 8 children's hospitals in the United States (2006-2014). Pneumococcal isolates were collected prospectively. Serotyping and antibiotic susceptibility were performed in a central laboratory. Clinical and laboratory data were collected retrospectively. Patients were divided into 3 subgroups: pre-PCV13 (2006-2009), transitional year (2010) and post-PCV13 (2011-2014). Dichotomous variables were analyzed by Χ2 test and continuous variables with non-parametric tests. Results. During this study, 391 of 1533 (25.5%) children with invasive pneumococcal disease (IPD) had PP. PP/IPD proportion decreased 28.6% (233/826 versus 109/537, p = 0.001). The total number of PP cases decreased 46.8% from 2006-2009 to 2011-2014 (figure). *Denominator is 223 for 2006-2009 and 105 for 2011-2014. The most common non-PCV13 STs during 2011-2014 were 33F (n = 6), 35B and 22F (n = 4 each). In 2014, the most common STs were 3 (n = 6), 19A (n = 4) and 35B (n = 3). In 2011-2014, 65% of patients with PP had not received a dose of PCV13. Clinical data was available from 297 patients; among them cases of bacteremic PP (96/160 versus 47/82), empyemas (101/173 versus 44/88), necrotizing PP (59/173 versus 25/88) and hemolytic-uremic syndrome (12/173 versus 2/88) remained unchanged after PCV13 introduction. Need for intensive care, mechanical ventilation and invasive procedure remained unchanged. Conclusion. Total number of PP cases decreased 46.8% in children after PCV13 introduction. PCV13 STs 19A and 3 were responsible for half of the cases of PP in 2011-2014. Disclosures. S. L. Kaplan, Forest Labs: Grant Investigator, Grant recipient Pfizer: Grant Investigator, Grant recipient