Review of recent pneumococcal infections with attention to vaccine and nonvaccine serotypes.

Conflicting data on the efficacy of the pneumococcal vaccine have continued to evolve. One important aspect of vaccine efficacy is related to the percentage of disease-causing serotypes contained in the vaccines. If disease-causing serotypes were to vary from place to place and population to population, vaccine efficacy would be variable and difficult to assess. We reviewed the literature on serotypic distribution of pneumococcal infection. Percentage of disease-causing serotypes covered by the 14-valent vaccine varied significantly from one study to another. Differences in age, hospital type, and source of isolation showed statistically significant serotypic distribution.