The development of 13-valent pneumococcal conjugate vaccine and its possible use in adults.

INTRODUCTION: Worldwide, Streptococcus pneumoniae causes significant morbidity and mortality. The 23-valent pneumococcal polysaccharide vaccine (PPSV23) has been recommended for use in persons aged 65 years and over and in adults with certain chronic medical conditions. Pneumococcal conjugate vaccines (PCVs) have been developed for use in infants and children aged less than 5 years, and are being studied for use in adult populations. AREAS COVERED: The different types of pneumococcal vaccines are discussed. Studies comparing PPSV23 and PCVs, as well as the results of the widespread use of 7-valent PCV are covered. The possible extension of the use of 13-valent PCV to adults, particularly to vulnerable populations, is discussed. The MEDLINE database was used to identify relevant studies from literature published in English between January 1977 and January 2011. All studies of adults aged over 18 years were considered for the review. EXPERT OPINION: Elderly individuals and adults with chronic medical conditions who are at increased risk for pneumococcal disease would benefit from more effective prevention than is provided by the currently recommended PPSV23.