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Legionnaires' Disease

(Legionnaires' Pneumonia)

Definition

Legionnaires' disease is a lung infection. It is a form of pneumonia . It got its name after it struck at the American Legionnaires Convention in 1976.

Causes

This disease is caused by the bacterium Legionella pneumophilia in most cases. 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 Legionella bacteria.

The Lungs

The infection does not move from one person to another.

Risk Factors

Factors that increase your chance for Legionnaires' disease include:

Advanced age

Smoking

Chronic lung disease

Weakened immune system (as with AIDS )

Kidney failure

Diabetes

Taking cortisone or other immunosuppressive drugs

Organ transplant patients

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

Treatment

This disease is usually treated with antibiotics.

If you are diagnosed with Legionnaires' disease, follow your doctor's instructions.

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.

RESOURCES:

Centers for Disease Control and Prevention (CDC)

http://www.cdc.gov

National Institute of Environmental Health Sciences

National Institutes of Health (NIH)

http://www.niehs.nih.gov

CANADIAN RESOURCES:

Capital Health Nova Scotia

http://www.cdha.nshealth.ca

Communicable Disease Control

Manitoba Health

http://www.gov.mb.ca

References:

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

Legionellosis resource site. 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.

Legionnaires' disease. Occupational Safety & Health Administration website. Available at: http://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.htm . Accessed December 31, 2012.

Pneumonia in adults. EBSCO DynaMed website. Available at: https://dynamed.ebscohost.com . Updated December 5, 2012. 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 March 2013 by Brian Randall, 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.