Legionnaires' disease is a lung infection. It is a form of pneumonia. It got its name from an outbreak at the American Legionnaires Convention in 1976.
This disease is caused by specific bacteria. The bacteria are most often found in sources of standing water. It may be found in cooling towers, HVAC systems, and air conditioners.
Legionnaires' disease can be contracted by breathing water vapor from a standing water source that contains the bacteria.
The infection does not move from one person to another.
Factors that may increase your chance of Legionnaires' disease include:
Your doctor will ask about your symptoms and medical history. A physical exam will be done.
Your doctor may need pictures of your chest. This can be done with a chest x-ray.
Your doctor may need tests of your bodily fluids. This can be done with:
Centers for Disease Control and Prevention
National Institute of Environmental Health Sciences
National Institutes of Health (NIH)
Capital Health Nova Scotia
Communicable Disease Control
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Legionnaires' disease. Occupational Safety and Health Administration website. Available at: https://www.osha.gov/dts/osta/otm/legionnaires/index.html. Accessed December 31, 2012.
Legionnaires' disease. Patient UK website. Available at: http://www.patient.co.uk/health/legionnaires-disease-leaflet. Accessed December 31, 2012.
Legionella infections. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed. Updated December 29, 2012. Accessed December 31, 2012.
Legionella (Legionnaires' disease and pontiac fever). Centers for Disease Control and Prevention website. Available at: http://www.cdc.gov/legionella/about/index.html. Updated June 1, 2011. Accessed December 31, 2012.
Top 10 things every clinician needs to know about Legionellosis. Centers for Disease Control and Prevention website. Available at: http://www.cdc.gov/legionella/clinicians.html. Updated June 1, 2011. Accessed December 31, 2012.
Last reviewed February 2015 by David L. Horn, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.