Pneumococcal resistance and serotype 19A in Pittsburgh-area children with acute otitis media before and after introduction of 7-valent pneumococcal polysaccharide vaccine

Clin Pediatr (Phila). 2011 Feb;50(2):114-20. doi: 10.1177/0009922810384259. Epub 2010 Nov 22.

Abstract

Methods: Before and after introduction of pneumococcal conjugate vaccine (PCV7), the authors obtained nasopharyngeal (NP) specimens from 3 groups of children aged 6 to 23 months with acute otitis media (AOM): group 1 (pre-PCV7), group 2 (early post-PCV7), and group 3 (late post-PCV7).

Results: Of the Streptococcus pneumoniae isolates, the proportion that were vaccine serotypes (VTs) declined progressively (60.4% vs 48.6% vs 5.2% in groups 1, 2, and 3, respectively; P < .001). Concurrently, increases occurred in the proportion of penicillin-nonsusceptible isolates (minimum inhibitory concentration >0.1 µg/mL; 26.7% vs 37.8% vs. 38.5%; P = .12); the proportion of isolates that were serotype 19A (4.0% vs 0% vs 25.9%; P < .001); and the proportion of 19A isolates that were penicillin-nonsusceptible (0% in group 1, 68.6% in group 3; P = .004).

Conclusion: Shifts in pneumococcal serotype distribution and increases in penicillin nonsusceptibility among pneumococcal isolates from children with AOM underscore the need for continuing bacteriological surveillance for future vaccine development.

Trial registration: ClinicalTrials.gov NCT00377260.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Disease
  • Drug Resistance, Bacterial*
  • Female
  • Humans
  • Infant
  • Male
  • Nasopharynx / microbiology
  • Otitis Media / immunology
  • Otitis Media / microbiology*
  • Pneumococcal Infections / microbiology
  • Pneumococcal Infections / prevention & control*
  • Pneumococcal Vaccines / administration & dosage
  • Pneumococcal Vaccines / immunology*
  • Serotyping
  • Streptococcus pneumoniae / classification*
  • Streptococcus pneumoniae / isolation & purification*
  • Vaccination

Substances

  • Pneumococcal Vaccines

Associated data

  • ClinicalTrials.gov/NCT00377260