Diseases

Legionnaires' disease

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Legionnaires' disease is a form of atypical pneumonia caused by any type of legionella bacteria. Signs and symptoms include cough, shortness of breath, high fever, muscle pains, and headaches. ... It is usually spread by breathing in mist that contains the bacteria.

SYMPTOMS

Legionnaires' disease usually develops two to 10 days after exposure to legionella bacteria. It frequently begins with the following signs and symptoms:

headache
muscle pain
chills
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 a fever, chills, headache and muscle aches. Pontiac fever doesn't infect your lungs, and symptoms usually clear within two to five days.

CAUSES

The bacterium legionella pneumophila is responsible for most cases of legionnaires' disease. Outdoors, legionella bacteria survive in soil and water, but rarely cause infections. Indoors, though, legionella bacteria can multiply in all kinds of water systems — hot tubs, air conditioners and mist sprayers in grocery store produce departments.
Although it's possible to contract legionnaires' disease from home plumbing systems, most outbreaks have occurred in large buildings, perhaps because complex systems allow the bacteria to grow and spread more easily.