Deconstructing Pneumococcal Progression from Colonization to Disease.

Despite advances in treatment and prevention, the pneumococcus continues to be a dominant cause of severe pneumonia and sepsis and of otitis media, sinusitis, and nonbacteremic pneumonia. Lewnard and colleagues (Infect Immun 86:e00727-17, 2018, https://doi.org/10.1128/IAI.00727-17) used a unique data set of nasopharyngeal and middle ear fluid samples to provide further insight into the progression of nasopharyngeal pneumococcal colonization to disease. They report the comparative rate of progression from colonization to otitis media by serotype, providing insight into how conjugate vaccines that do not reduce the overall prevalence of pneumococci in the nasopharynx dramatically impact the incidence of acute and complex otitis media.