Streptococcus pneumoniae is the predominant
otitis media pathogen and its prevention through effective vaccination could diminish childhood illness and
antibiotic use. This paper reviews 5 pneumococcal
conjugate vaccine (PCV) trials that used
otitis media as an endpoint: Northern California Kaiser Permanente (NCKP;
vaccine, 7-valent PCV [PCV7]-CRM); Finnish
Otitis Media (FinOM;
vaccines, PCV7-CRM or PCV7-OMPC); Native American Trial (
vaccine, PCV7-CRM); Pneumococcal
Otitis Efficacy Trial (POET;
vaccine, 11-valent PCV [PCV11]-PD). For the microbiological endpoint,
vaccine efficacy against
vaccine-serotype pneumococcal
otitis media was about 60% across trials. Against the clinical endpoint of all episodes,
vaccine efficacy was 7% (PCV7-CRM/NCKP), 6% (PCV7-CRM/FinOM), -1% (PCV7-OMPC/FinOM), and -0.4% (PCV7-CRM/Native American Trial); 34% against first episodes of ear, nose, and throat specialist-referral cases (PCV11-PD/POET). Both follow-up through 2 years of age, for the 5 trials, and long-term follow-up, for PCV7-CRM/NCKP and PCV7-CRM/FinOM, demonstrated greater
vaccine efficacy against recurrent AOM and
tympanostomy-tube placement, suggesting that vaccination against early episodes of AOM may prevent subsequent episodes of complicated
otitis media. Although study designs varied by primary endpoint measured, age at follow-up, source of middle-ear fluid for culture, case ascertainment, and type of randomization, each clinical trial demonstrated
vaccine efficacy against microbiological and/or clinical
otitis media.