Following usage of the pneumococcal conjugate vaccine in children, the incidence of invasive pneumococcal disease declined in both children and adults (reflecting herd immunity). However, emergence of serotypes not encompassed in the vaccine is worrisome, and may be associated with heightened antimicrobial resistance and virulence. Continued vigilance for emergence of novel serotypes and development of vaccines with expanded coverage and immunogenicity will be critical for optimal prevention of pneumococcal infections.