Pneumococcal Conjugated Vaccines Decreased Acute Otitis Media Burden: A Population-Based Study in Israel

Abstract

To study time trends in all-cause acute otitis media (AOM) burden by calculating incidence rates of AOM episodes and recurrent acute otitis media (rAOM) cases in highly immunized pediatric population during the pre- and post-pneumococcal conjugated vaccine (PCV) years. In this population-based study, AOM episodes and rAOM cases were identified in Clalit Health Services-insured Israeli children aged 0-10years between 2005 and 2018 by using a data-sharing platform. Because a near-sequential implementation of PCV-7/PCV-13 occurred within a 1-year period (2009/2010), we compared AOM visits before (2005-July 2009) and after (August 2009-2018) the introduction of PCVs. We focused on children younger than 2years of age, who are the target population of PCVs and are at AOM peak age. We identified 805 389 AOM episodes contributed by 270 137 children. The median number of AOM episodes was 2 (IQR 1-4). A downward trend of incidence rates of AOM episodes was observed during the post-PCV years in children younger than age 9years (P<.001). The largest decrease (21%) was observed in children younger than 1year, from 807/1000 children during the pre-PCV years to 640/1000 during the post-PCV years (P<.001). An average annual decrease of ∼14/1000 AOM episodes was calculated in children younger than 1year old (β=-13.39, 95% CI -16.25 to -10.53, P<.001). Of rAOM cases, documented in 84 237 (31.2%) children, 74% were in children younger than 2years, and 55% were in boys. The risk to develop rAOM significantly decreased during the post-PCV years in children younger than 2years (hazard ratio 0.893, 95% CI 0.878-0.908; P<.001). AOM burden significantly decreased following PCVs introduction in highly immunized children.