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Streptococcus pneumoniae. Adele Ricciardi. Pneumonia - inflammatory condition of the lung. PNEUMONIA CAN BE CAUSED BY: VIRUSES FUNGI BACTERIA. Symptoms Diagnosis. Chest x-ray (in hospitals and clinics) Blood test Sputum culture physical examination CT scan.
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Streptococcus pneumoniae Adele Ricciardi
Pneumonia-inflammatory condition of the lung PNEUMONIA CAN BE CAUSED BY: VIRUSES FUNGI BACTERIA
Symptoms Diagnosis • Chest x-ray (in hospitals and clinics) • Blood test • Sputum culture • physical examination • CT scan • cough (often produces rust colored mucus) • fever and chills • shortness of breath • chest pain • fatigue
Streptococcus pneumoniae • nasopharynx of healthy people • Gram-positive bacteria • Paired (diplococci) or appear in chains • May also infect brain (pneumococcal meningitis) and blood stream (pneumococcus septicemia) Scanning Electron Micrograph of Streptococcus pneumoniae. Source: CDC/ R. Facklam, J. Carr
S. pneumoniae was first isolated in 1881,S. pneumoniae was first isolated in 1881,but it still remains the number 1 killer of children under 5 today.but it still remains the number 1 killer of children under 5 today
The Toll 4 million deaths every year • half of these deaths - children under age 5 • 5,500 children die from pneumonia every day • 98% of children who die of pneumonia live in developing countries • contributes to the cycle of poverty
S. Pneumoniae -Virulence • Polysaccharide capsule, > 90 serotypes • Resistance to phagocytosis and antibiotics
Pneumococci in intimate contact with lung cells show reduced capsular polysaccharide
Virulence- Pneumolysin • Toxin • Cholesterol-dependent cytolysin • Cytokine synthesis • Inflammatory response
Pneumococcal conjugate vaccine • Elicits antibodies against the seven most common capsular types • Sero-specific • Results: • Decrease nasopharyngeal colonization • Reduce disease of included serotypes • Problems: • Expensive • Alter serotype distribution
Use of pneumococcal conjugate vaccine is limited to parts of the developing world
Pneumonia will continue to kill Unless we do something about it…
Treatment • Antibiotics, <$1/dose • Amoxicillin – inhibit cell wall formation • Erythromycin- inhibit protein synthesis • 1 out of 5 children with pneumonia receives antibiotics
They may not be excited now...but they will be. This vaccine deal could save900,000 lives by 2015.
References • Bruyn, G.W, Zegers, B. M, R. van Furth. Mechanisms of Host Defense against Infection with Streptococcus pneumoniae. Clinical Infections Diseases 1992;14;251-62. • Daniels, Briles, Mirza, Hakasson, Briles. Capsule does not block antibody binding to PspA, a surface virulence protein of Streptococcus pneumoniae. Microbial Pathogenesis. 40;2006;228-233. • Alonsodevelasco, Verhuel, Verhoef, Snipe. Atreptococcus pneumoniae: Virulence Factors, Pathogenesis and Vaccines. Microbiological Reviews. Dec. 1995, 591-603. • Hsieh, Lee, Shao, Chang, Huang. The Transforming Streptococcus Pneumoniae in the 21st century. Chang Gung Med J Vo. 30 No. 2 2008;31:117-24 • Hammerschmidt, Wolff, Hocke, Rosseau, Muller, Rohde. Illustration of Pneumonococcal Polysacharide Capsule during adherence and invasion of epithelial cells. Infection and Immunity. 2005; 4653-4667. • Kadioglu, Weiser, Paton, Andrew. The role of streptococcus pneumoniae virulence factors in host respiratory colonization and disease. Nature. 2008;6. • World Health Organization: The top 10 causes of death. October 2008. http://www.who.int/mediacentre/factsheets/fs310/en/index.html[2] Rudan I, Boschi-Pinto C, Biloglav Z, Mulholland K, Campbell H. Epidemiology and etiology of childhood pneumonia. Bull World Health Organ. 2008;86:408–16. • World Health Organization. World health statistics 2009. Geneva: World Health Organization; 2008. http://www.who.int/whosis/whostat/EN_WHS09_Full.pdf • Rudan I, Boschi-Pinto C, Biloglav Z, Mulholland K, Campbell H. Epidemiology and etiology of childhood pneumonia. Bull World Health Organ. 2008;86:408–16. • World Health Organization. World health statistics 2006. Geneva: World Health Organization; 2006. http://www.who.int/whosis/whostat2006.pdf. • World Health Organization. World health statistics 2006. Geneva: World Health Organization; 2006. http://www.who.int/whosis/whostat2006.pdf.. • Rudan I, Boschi-Pinto C, Biloglav Z, Mulholland K, Campbell H. Epidemiology and etiology of childhood pneumonia. Bull World Health Organ. 2008;86:408–16. • Rudan I, Tomaskovic L, Boschi-Pinto C, Campbell H. Global estimate of the incidence of clinical pneumonia among children under five years of age. Bull World Health Organ. 2004;82:895–903.