Impact of 13-valent pneumococcal conjugate vaccine on otitis media bacteriology.

Objectives: To determine the microbiology of otitis media (OM) since the introduction of the 13-valent pneumococcal conjugate vaccine (PCV13) in February 2010.

Methods: Middle ear effusion from a pediatric Otolaryngology population undergoing pressure equalization tube (PET) placement was obtained and sent for aerobic culture and antibiotic susceptibility testing between August 2012 and April 2013. Vaccination records were obtained and statistical analysis was completed.

Results: During the 8-month period, 236 ears were evaluated, and of those 39 ears were found to have positive cultures. The single nonvaccine Streptococcus pneumoniae (serotype 16) isolate was obtained from a PCV7-only vaccinated patient and was penicillin susceptible. The three most common isolates were Staphylococcus coagulase negative (57%), Haemophilus influenzae (17%), and Moraxella catarrhalis (7%).

Conclusions: This study is the first to assess the bacteriology of OM in a pediatric population undergoing PET placement in the immediate post-PCV13 era. Our study is limited by sample size; however, the lack of S. pneumoniae cultures indicates that PCV13 has had a significant impact on pneumococcal infections during these initial years following licensure.