Pan-serotype Reduction in Progression of Streptococcus pneumoniae to Otitis Media After Rollout of Pneumococcal Conjugate Vaccines

BackgroundReductions in otitis media (OM) burden following rollout of pneumococcal conjugate vaccines (PCVs) have exceeded predictions of vaccine impact. In settings with active surveillance, reductions in OM caused by vaccine-targeted pneumococcal serotypes have co-occurred with reductions in OM caused by other pathogens carried in the upper-respiratory tract of children. To understand these changes, we investigated the progression of vaccine-targeted and non-vaccine pneumococcal serotypes from carriage to OM before and after vaccine rollout.MethodsNasopharyngeal carriage prevalence of pneumococcus was monitored in prospective studies of Bedouin and Jewish children