Frequency of Acute Otitis Media in Children Under 24 Months of Age Before and After the Introduction of the 10-valent Pneumococcal Conjugate Vaccine Into the National Immunization Program in Chile.

Background: Streptococcus pneumoniae is the leading cause of acute otitis media (AOM). Ten-valent pneumococcal conjugated vaccine (PCV-10) was introduced to the Chilean National Immunization Program (NIP) in 2011. The aim of this study was to estimate the frequency of AOM in children <24 months of age attending the emergency department (ED) of Hospital Sótero del Río (HSR) 4 years before and 4 years after the introduction of PCV-10 in the Chilean NIP.