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:
- Advanced age
- Chronic lung disease
- Weakened immune system
- Kidney failure
- Taking cortisone or other immunosuppressive drugs
- History of organ transplant
Symptoms may include:
- Fever (often high)
- Chills and muscle aches
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:
- Urine tests
- Sputum tests
- Blood tests
This disease is usually treated with antibiotics.
Proper design, maintenance, and cleaning of high-risk areas can reduce the risk of spreading the disease. This includes any area with standing water.
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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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.