Streptococcus pneumoniae- the pneumococcus- affects children and adults worldwide. Invasive pneumococcal disease, including pneumonia, meningitis and bacteraemia, has been linked annually to the deaths of millions of children. The pneumococcus is also a significant contributor to mucosal infections such as acute otitis media and sinusitis. Though pneumococcal infections can occur at any age, persons at greatest risk include children younger than 2 years of age and adults aged 65 years or more. Rates of pneumococcal disease and the prevalence of pneumococcal serotypes vary by geographic location and patient age. Accurate ascertainment and sound epidemiological data are essential for the rational development of effective programmes for prevention and treatment. Pneumococcal resistance to penicillin and other antibiotics has emerged rapidly in recent years, highlighting the importance of vaccine development. Newer pneumococcal vaccines, such as those conjugated to protein carriers, can now overcome the limitations of older polysaccharide vaccines. Such conjugated vaccines induce excellent immune responses even in infants and young children and they may also reduce asymptomatic nasopharyngeal carriage of pneumococci. Pneumococcal 7-valent conjugated vaccine PNCRM7 contains common prevalent serotypes coupled to a nontoxic diphtheria variant (CRM197). This vaccine has demonstrated high efficacy against invasive pneumococcal disease in clinical trials in infants and young children and is currently licensed for use in the United States and selected countries in Europe and Latin America.
Conclusion: across Europe, pneumococcal infection is responsible for considerable morbidity and mortality, particularly in the very young and the elderly, groups whose members respond poorly to non-conjugated vaccines. The advent of new conjugated pneumococcal vaccines now offers an exciting opportunity in developed countries to reduce both the current burden of disease and the threat of rising antibiotic resistance. Rolling out the use of such vaccines across Europe must be accompanied by detailed ongoing surveillance in order to detect any changes that might occur in the pattern of pneumococcal serotypes.