Pneumococcal conjugate vaccines: what do we know and what do we need?

Pneumococcal disease is complex with many disease manifestations. Streptococcus pneumoniae causes a variety of illnesses, from acute otitis media to clinical pneumonia and invasive pneumococcal disease (IPD). Immunization is among the most successful and cost-effective means of controlling pneumococcal disease. Pneumococcal conjugate vaccines (PCVs) have been approved for use in children aged up to 9 years since 2000; to date, widespread global uptake of PCVs has not yet been achieved. The heptavalent pneumococcal conjugate vaccine (PCV7) is the only PCV with large-scale controlled trials demonstrating efficacy and documented effectiveness across various disease manifestations. The benefits of including PCV7 in national immunization programmes include decreased infant mortality, reduced vaccine serotype IPD, minimized racial and social disparities in rates of incidence of pneumococcal disease, reduced disease due to nonsusceptible serotypes, reduction in pneumonia and AOM and indirect effects (herd immunity).