Overview

Definition

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.

Causes

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 Lungs
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The infection is not spread from one person to another.

Risk Factors

Factors that may increase the chances of Legionnaires disease:

  • Advanced age
  • Smoking
  • Chronic lung disease
  • Weakened immune system
  • Kidney failure
  • Diabetes
  • Taking cortisone or other immunosuppressive drugs
  • History of organ transplant

SymptomsandDiagnosis

Symptoms

Symptoms may include:

  • Fatigue
  • Fever (often high)
  • Chills and muscle aches
  • Cough
  • Headache

Diagnosis

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

Treatments

Treatment

This disease is usually treated with antibiotics.

Prevention

Proper design, maintenance, and cleaning of high-risk areas can reduce the risk of spreading the disease. This includes any area with standing water.

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.

Edits to original content made by Denver Health.

a (Legionnaires Pneumonia)

RESOURCES

Centers for Disease Control and Prevention https://www.cdc.gov 

National Institute of Environmental Health Sciences https://www.niehs.nih.gov 

CANADIAN RESOURCES

Nova Scotia Health Authority http://www.nshealth.ca 

Public Health Agency of Canada https://www.canada.ca 

References

Arcavi L, Benowitz NL. Cigarette smoking and infection. Arch Intern Med. 2004;164(20):2206-2216.

Community-acquired pneumonia in adults. EBSCO DynaMed Plus website. Available at:  http://www.dynamed.com/topics/dmp~AN~T115170/Community-acquired-pneumonia-in-adults  . Updated December 18, 2017. Accessed February 16, 2018.

Legionella infections. EBSCO DynaMed Plus website. Available at:  http://www.dynamed.com/topics/dmp~AN~T904756/Legionella-infections  . Updated May 20, 2016. Accessed February 16, 2018.

Legionella infections. Merck Manual Professional Version website. Available at: http://www.merckmanuals.com/professional/infectious-diseases/gram-negative-bacilli/legionella-infections. Updated May 2016. Accessed February 16, 2018.

Legionella (Legionnaires' disease and Pontiac fever). Centers for Disease Control and Prevention website. Available at: https://www.cdc.gov/legionella/about/index.html. Updated May 31, 2016. Accessed February 16, 2018.