Understanding the burden of pneumococcal disease in adults.

Streptococcus pneumoniae causes different types of acute, invasive and non-invasive clinical infections, being the most frequently detected pathogen responsible for community-acquired pneumonia. Pneumococcal pneumonia is accompanied by bacteraemia in 10-30% of cases. Streptococcus pneumoniae is gaining resistance to the in vitro activity of several antimicrobial agents and, even if questions remain regarding the clinical impact of this phenomenon, more and more reports indicate that antibiotic resistance can lead to more treatment failures if not higher mortality. Use of the 23-valent anti-pneumococcal vaccine appears to offer subpotimal protection against pneumococcal disease, particularly among high-risk adult populations. Vaccination against S. pneumoniae with new conjugate vaccines seems to be the most promising field for real improvement in the management of pneumococcal infections in adults.