Legionnaires' disease usually develops two to 10 days after exposure to legionella bacteria. It frequently begins with the following signs and symptoms:
- Muscle pain
- Fever that may be 104 F (40 C) or higher
By the second or third day, you'll develop other signs and symptoms that may include:
- Cough, which may bring up mucus and sometimes blood
- Shortness of breath
- Chest pain
- Gastrointestinal symptoms, such as nausea, vomiting and diarrhea
- Confusion or other mental changes
Although Legionnaires' disease primarily affects the lungs, it occasionally can cause infections in wounds and in other parts of the body, including the heart.
A mild form of Legionnaires' disease — known as Pontiac fever — may produce signs and symptoms including fever, chills, headache and muscle aches. Pontiac fever doesn't infect your lungs, and symptoms usually clear within two to five days.
When to see a doctor
See your doctor if you think you've been exposed to legionella bacteria. Diagnosing and treating Legionnaires' disease as soon as possible can help shorten the recovery period and prevent serious complications. For people at high risk, prompt treatment is critical.
Jan. 02, 2014
- Pedro-Botet ML, et al. Epidemiology and pathogenesis of Legionella infection. http://www.uptodate.com/home. Accessed June 26, 2013.
- Legionella (Legionnaires' disease and Pontiac fever). Centers for Disease Control and Prevention. http://www.cdc.gov/legionella/index.html. Accessed June 26, 2013.
- Longo DL, et al. Harrison's Online. 18th ed. New York, N.Y.: The McGraw-Hill Companies; 2012. http://www.accessmedicine.com/resourceTOC.aspx?resourceID=4. Accessed June 26, 2013.
- Pedro-Botet ML, et al. Clinical manifestations and diagnosis of legionella infection. http://www.uptodate.com/home. Accessed June 26, 2013.
- Mandell GL, et al. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, Pa.: Churchill Livingstone Elsevier; 2010. http://www.mdconsult.com/books/about.do?about=true&eid=4-u1.0-B978-0-443-06839-3..X0001-X--TOP&isbn=978-0-443-06839-3&uniqId=230100505-57. June 26, 2013.
- Pedro-Botet ML, et al. Treatment and prevention of legionella infection. http://www.uptodate.com/home. Accessed June 26, 2013.
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