Otopathogen Prevalence Altered Since Pneumococcal Vaccine Introduction
Acute otitis media etiologic agents have changed in the years since PCV introduction.
A new study published in Pediatrics showed that acute otitis media (AOM) had similar risk factors during a 10-year postpneumococcal conjugate vaccine (PCV) period, but the pathogens causing ear infections changed during the same timeframe.
In this prospective study, 615 children were followed between the ages of 6 and 36 months from June 2006 to June 2016. To determine risk factors and epidemiology of AOM and otitis-proneness (≥3 episodes of AOM within 6 months or ≥4 within a year), nasopharyngeal and blood samples were collected at each AOM diagnosis and during regular intervals. Tympanocentesis and bacterial culture of middle ear fluid confirmed all diagnoses of AOM.
Peak incidence of AOM occurred between 6 and 12 months of age, with 23% of children experiencing their first episode of acute otitis media by 1 year of age and 60% of children experiencing their first episode by 3 years of age. A total of 24% of children had experienced ≥3 AOM episodes by age 3 years.
Factors associated with a significantly increased risk for AOM included male sex, non-Hispanic white race, family history of recurrent acute otitis media, day care attendance, and early occurrence of AOM.
Male sex, day care attendance, and family history of AOM were associated with otitis proneness; however, breast-feeding in the first 6 months of life was protective from AOM.
Since the introduction of the 13-valent PCV, the prevalence of Moraxella catarrhalis as the pathogenic cause of AOM increased, whereas the prevalence of Streptococcus pneumoniae decreased. Throughout the 10-year study, Haemophilus influenzae was a common acute otitis media-causing pathogen, with a rise in prevalence in 2016.
The study authors concluded that day care attendance and AOM early in life remain important risk factors for AOM, but the etiologic agents have changed since PCV introduction.
"We conclude that much of the shift in otopathogen prevalence can be attributed to the influence of the [13-valent PCV] vaccine and changes in diagnostic criteria for AOM vs otitis media with effusion," the study authors concluded.
Kaur R, Morris M, Pichichero ME. Epidemiology of acute otitis media in the postpneumococcal conjugate vaccine era [published online August 7, 2017]. Pediatrics. doi: 10.1542/peds.2017-0181