Conjugate pneumococcal vaccines: an overview

A seven-valent conjugate pneumococcal vaccine has been shown to have dramatic efficacy against invasive pneumococcal disease and lesser efficacy against otitis media and pneumonia. This vaccine was licensed for use in infants in the United States in February 2000 and is recommended there for routine use in infants and catch-up vaccination in high-risk children. Specific regional pneumococcal vaccines are not needed; nine to 11 serotypes cover most pneumococcal disease in most parts of the world; nine- and 11-valent conjugate vaccines are currently being developed for the global market. There is evidence of serotype replacement in vaccine recipients (in both carriage and disease), which might reduce overall vaccine effectiveness, There is also evidence that vaccines may reduce rates of antimicrobial resistance in pneumococci. Studies of the burden of pneumococcal disease as well as program support are needed to assist developing countries to introduce these expensive vaccines.