A little bit detailed:

What is it?

The air sacs in the lungs are filled with pus and other liquid which causes a lack of oxygen in the body. Because of this (and eventually spreading infection) may cause death. Until 1936, pneumonia was regarded the No.1 cause of death: in 1998, the infectious disease is ranked as sixth in the leading causes of death


  • Bacteria:
    Pneumonia bacteria are present in every 'healthy person', but can 'attack' if the body has been weakened by serious illness, old age, wrong food on a daily basis or alcohol. Streptococcus pneumoniae is the most common cause of bacterial pneumonia.
  • Viral:
    Probably half of the pneumonia variants are caused by viri, esp. in children.
    Most of these variants are shortlasting, though.
  • Mycoplasma:
    Mycoplasmas are the smallest living agents of disease unclassified being viri or bacteria.
    Generally they cause light forms of pneumonia.
  • Other:
    Other less known variants can be caused by fungi, gases, food or dust. Foreign 'bodies' in your body (like tumors) may be 'promoting' pneumonia too.