Improving the protection against Streptococcus pneumoniae with the new generation 13-valent pneumococcal conjugate vaccine.

The wide use of the 7-valent Pneumococcal Conjugate Vaccine (PCV7) determined, during the last decade, a dramatic decline in the incidence of Invasive Pneumococcal Diseases (IPD) in infants and children, and also among the non-vaccinated population through the phenomenon known as "herd protection". Furthermore a significant reduction of some non-IPD, such as Community Acquired Pneumonia (CAP) and Acute Otitis Media (AOM) was reported among the pediatric population. At the same time, the high vaccination coverage rates reached with PCV7 contributed to modify the ecology of Streptococcus pneumoniae (Sp), favoring the emergence of some serotypes not included in PCV7 and involved in IPD (replacement phenomenon), thus partially affecting the positive effects of the pediatric immunization programs. To remedy these shortcomings, a new generation of conjugate vaccines, with an enlarged antigenic spectrum of activity than PCV7, has been available since 2010. In particular, the 13-valent Pneumococcal Conjugate Vaccine (PCV13) has been authorized for active prevention of IPD, CAP and AOM in infants and children aged between 6 months and 5 years. More recently, in September 2011, the European Medicine Agency extended the indication for its use to include active immunization of adults aged > or = 50 years for the prevention of IPD, thus opening new interesting opportunities to improve the control of pneumococcal disease among the entire population. The most interesting results from clinical trials using PCV13 in both children and adults are reported and discussed in details.