Ceyhan M. (Department of Pediatrics, Hacettepe University Faculty of Medicine, Ankara, Turkey). Pneumococcal infections and immunization in children. Çocuk Sağlığı ve Hastalıkları Dergisi 2009; 52: 91-99. Pneumococcal diseases are among the major public health problems worldwide. Many children die of pneumococcal diseases annually, mostly young children in developing countries. It is the leading cause of some important invasive infections including pneumonia, meningitis and bacteremia and of some common non-invasive infections like otitis media and sinusitis. The recent development of widespread microbial resistance to essential antibiotics underlines the urgent need for efficient pneumococcal vaccines. Differences in the composition of the surrounded capsule permit serological differentiation between 91 capsular types, some of which are frequently associated with pneumococcal disease, others rarely. Vaccination is the only available tool to prevent pneumococcal disease. Although in the healthy elderly population the polysaccharide vaccine provides relatively efficient protection against invasive pneumococcal diseases, children under two years of age do not consistently develop immunity following vaccination. After extensive clinical trials, a sevenvalent protein-polysaccharide conjugated vaccine has been licensed and is being used in national immunization programs in more than 20 countries, including Turkey. This vaccine is being used in routine immunization beginning at two months of age. The most effective vaccination schedule is 3+1 according to available data. Protective efficacy of this vaccine is about 70% to 90% against meningitis, 20% against pneumonia, and 6% against otitis media in the childhood period. There is some new data indicating a 40% reduction in otitis media incidence in the USA. Two studies from Turkey have shown a serotype coverage of about 85% to 90% in invasive isolates. After the use of conjugated vaccine, a decline in the incidence of invasive pneumococcal infections has been observed in adults due to herd immunity. Two new conjugated vaccines, one 10-valent vaccine including Haemophilus influenza D protein and one 13-valent vaccine, are under evaluation for licensure. Key words: pneumococcal infection, vaccine, immunization.

Keywords: pnömokok enfeksiyonları, aşı, immünizasyon.