Pneumonia is defined as the presence of fluid in the lungs.¹ Typical symptoms are cough, fever, chills, and fatigue. They are often accompanied by nasal congestion, sore throat, laryngitis or acute bronchitis. S. pneumoniae is the leading cause of community acquired pneumonia² affecting the very young, the elderly, and immunocompromised patients with the greatest frequency.³ Even after extensive testing, the cause of pneumonia is only determined in approximately 50% of patients. The most common bacterial causes are Streptococcus pneumoniae, Haemophilus influenzae, Mycoplasma pneumoniae, Chlamydia pneumoniae, and Legionella.⁴

For more information about pneumonia, please follow the links indicated below:

• CDC: Infectious Disease Information: Pneumonia
  
• The Lung Association: Penumonia
  
• The Nemours Foundation: KidsHealth.org: Penumonia
  

¹ Dorland's Pocket Medical Dictionary. 1977. 22nd ed. W.B .Saunders Company, Philadelphia.
²Plouffe J, Moore S, Davis R, Facklam R. Serotypes of Streptococcus pneumoniae blood culture isolates from adults in Franklin County, Ohio.1994. J Clin Microbiol. 32:1606-1607.
³ Feldman, C., and K. P. Klugman. 1997. Pneumococcal infections. Curr Opin Infect Dis 10:110-115.
⁴ Bartlett J and C.J. Grace. 2003. Community-Acquired Pneumonia and Bronchitis, p. 227-250, in Medical Management of Infectious Disease, CJ Grace (ed.), Marcel Dekker, Inc., New York.