Nasopharyngeal carriage of respiratory pathogens in children undergoing pressure equalization tube placement in the era of pneumococcal protein conjugate vaccine use.

Abstract

To define carriage of bacterial respiratory pathogens in children undergoing pressure equalization tube placement. Nasopharyngeal cultures were performed during tube placement. Antibiotic susceptibilities and serotypes of pneumococci were determined. Sixty-nine Streptococcus pneumoniae, 72 Haemophilus influenzae (41% beta-lactamase positive), and 39 Moraxella catarrhalis (all beta-lactamase positive) were isolated from 201 children. Overall, 42% of pneumococci were nonsusceptible to penicillin, and 34.8% were resistant to macrolides. In relation to the pneumococcal conjugate vaccine, 17.4% were vaccine, 31.9% vaccine-related, and 50.7% nonvaccine serotypes. Twenty-five percent of children colonized with pneumococci carried antibiotic resistant nonvaccine serotypes rarely detected before the introduction of pneumococcal conjugate vaccine, including serotype 19A isolates (7%) resistant to all oral agents tested and type 35B isolates (12%) nonsusceptible to penicillin and cefuroxime. Pneumococcal colonization suggests replacement of vaccine serotypes with vaccine related and nonvaccine serotypes, many of which are resistant to common oral antimicrobials.