• Lung inflammation, which is usually caused by an infection
  • Severe form of pneumonia
  • Caused by bacteria called Legionella


  • A fever above 104°F
  • Chills
  • A cough, with or without mucus or blood
  • Headaches
  • Muscle aches
  • Loss of appetite
  • Chest pain
  • Fatigue
  • Changes to the mental state, such as confusion


  • Legionella usually live in warm freshwater

Common Locations:

  • Hot tubs
  • Whirlpool spas
  • Swimming pools
  • Public showers
  • Humidifiers
  • Fountains
  • Natural bodies of water, such as lakes, rivers, and creeks

Risk Factors

  • Being 50 years of age or over
  • Weakened immune system
  • Chronic lung disease
  • Job that involves maintaining cooling or air conditioning systems
  • Smoking and alcohol consumption

Diagnostic Tests

  • Blood tests
  • Chest X-ray
  • Tests on a sample of sputum or lung tissue
  • CT scan of brain or a spinal tap (lumbar puncture)


  • Treated with antibiotics
  • Duration of treatment depends on severity of the disease


  • Erythromycin
  • Clarithromycin


  • Disinfect and clean cooling towers
  • Avoid smoking
  • Regularly drain and clean pools and hot tubs
  • Use chemical treatments, such as chlorine, in pools and spas
  • Keep hot water systems above 140°F
  • Keep the cold water systems below 68°F
  • Avoid water systems that could be contaminated
  • Seek medical advice if any symptoms develop