Mastoiditis with Streptococcus pneumoniae serotype 19A in one-dose PCV13 vaccinated three-month-old infant.

Pneumococcal conjugate vaccines (PCV) have been widely used in high-income countries for more than a decade, resulting in a dramatic reduction in pneumococcal disease caused by vaccine serotypes. PCV has been included in Turkey's National Immunization Programme since 2009 with PCV7 and continued with PCV13 from 2011. We presented a three-month-old infant who developed mastoiditis secondary to S. pneumoniae serotype 19A after acute otitis media.