Trends in Pediatric Complicated Pneumonia in an Ontario Local Health Integration Network

Area of Science:

• Pediatric Infectious Diseases
• Vaccinology
• Pulmonary Medicine

Background:

• The 7-valent pneumococcal vaccine (PCV7) reduced invasive pneumococcal disease but was associated with increased empyema rates.
• Pediatric complicated pneumonia (PCOMP) encompasses serious lung infections like empyema and necrotizing pneumonia.
• Understanding PCOMP trends after PCV introduction is crucial for public health.

Purpose of the Study:

• To examine hospitalization trends for pediatric complicated pneumonia (PCOMP) in Eastern Ontario, Canada.
• To assess the impact of the 13-valent pneumococcal vaccine (PCV13) on PCOMP incidence.
• To identify changes in PCOMP rates in relation to PCV7 and PCV13 introduction.

Main Methods:

• Retrospective chart review of previously healthy children admitted with PCOMP (2002-2015).
• Included conditions: empyema, parapneumonic effusion, necrotizing pneumonia, lung abscess.
• Analysis of admission rates before and after PCV7 and PCV13 introduction.

Main Results:

• 371 children with PCOMP were analyzed; median age was four years; 50.8% required chest tubes.
• PCOMP admissions peaked between 2009-2012, coinciding with PCV7 rollout and H1N1 pandemic.
• Incidence of PCOMP in likely PCV13-vaccinated children returned to pre-PCV7 levels.
• PCOMP rates remained elevated in older, unvaccinated children post-PCV13 introduction.

Conclusions:

• PCV13 appears effective in reducing PCOMP incidence in vaccinated children.
• Elevated PCOMP rates in unvaccinated older children persist post-PCV13.
• Widespread PCV13 uptake and herd immunity are expected to further decrease PCOMP rates.