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Legionnaires Disease

Authors:
  • Cynthia M. Johnson, MA
Publication Type:

Condition

Legionnaires Disease

(Legionnaires Pneumonia)

Definition

Legionnaires disease is a lung infection. It is a form of pneumonia.

Causes

Legionnaires disease is caused by a type of bacteria found in sources of standing water, such as cooling towers, HVAC systems, and air conditioners.

The bacteria is inhaled in water vapor from a contaminated water source. From there, it enters the lungs. The infection does not pass from person to person.

The Lungs.

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Nucleus factsheet imagehttp://services.epnet.com/getimage.aspx?imageiid=49204920BQ00030.jpgBQ00030.jpgNULLjpgNose airway to lungsNULL\\filer01a\Intellect\images\BQ00030.jpgNULL11NULL2003-04-163803904920_11709Copyright © Nucleus Medical Media, Inc.

Risk Factors

Legionnaires disease is more common in people over 50 years of age. Other things that raise the risk are:

  • A weak immune system
  • Exposure to contaminated water
  • Smoking
  • Long term lung disease
  • Kidney failure
  • Diabetes

Symptoms

Symptoms may include:

  • Tiredness
  • Fever (often high)
  • Chills and muscle aches
  • Cough
  • Headache
  • Nausea and vomiting
  • Loose stools

Diagnosis

The doctor will ask about symptoms and past health. A physical exam will be done. Urine, blood, and coughed fluid may also be tested. A chest x-ray may be done to get pictures of the lungs. Tests will confirm the diagnosis.

Treatment

Legionnaires disease is treated with antibiotics to clear the infection.

Prevention

Proper water management can lower the risk of infection.

RESOURCES:

CANADIAN RESOURCES:

CANADIAN RESOURCES:

References

  • Cunha BA, Burillo A, et al. Legionnaires' disease. Lancet. 2016;387(10016):376-385.
  • Legionella infections. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/legionella-infections.
  • Legionella infections. Merck Manual Professional Version website. Available at: http://www.merckmanuals.com/professional/infectious-diseases/gram-negative-bacilli/legionella-infections.
  • Legionella (Legionnaires' disease and Pontiac fever). Centers for Disease Control and Prevention website. Available at: https://www.cdc.gov/legionella/about/index.html.

Contributors

  • David L. Horn, MD, FACP
Last Updated:
2023-06-01

(C) Copyright 2023 EBSCO Information Services

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.