What is Legionellosis?

Legionellosis is an infection caused by the bacterium Legionella pneumophila. The severe form of legionellosis (Legionnaires' disease) can result in pneumonia. The milder form of this disease (Pontiac fever) requires no specific treatment.

Legionnaires' disease got its name in 1976 when an outbreak of pneumonia occurred among persons attending a Convention of American Legion in Philadelphia. Later, the bacterium causing this illness was named Legionella.

How common is Legionellosis?

Approximately 8,000 to 18,000 cases of Legionnaires’ disease are documented in the United States every year.

How severe is Legionellosis?

The milder form of this respiratory illness is called Pontiac fever, and the more sever form of legionellosis that causes pneumonia is called Legionnaires' disease.

Patients suffering from Pontiac fever usually recover within 2-5 days, and generally do not require any treatment. On the other hand, the severe form of this disease (Legionnaires disease) can result in up to 30% fatality rates.

Where are Legionella bacteria found?

Legionella can be found in:

• Creeks,
• Ponds,
• Potting soil,
• Warm and stagnant waters,
• Plumbing systems,
• Hot water tubs,
• Hot water tanks,
• Cooling tower water tanks,
• Whirlpool spas,
• Showers, and
• Condensers of large air conditioning systems.

It is not very common for Legionella bacteria to be found in residential and automobile air conditioners.

How is Legionellosis spread?

The legionellosis disease is spread when a person inhales airbourne mists containing Legionella bacteria. The legionellosis disease can not be spread from one person to another through contact.

Who is more likey to develop Legionellosis?

The legionellosis disease mostly occurs in middle-aged adults. Other risk factors include:

• Heavy Smokers,
• Chronic lung disease patients,
• Persons with impaired immune systems,
• Persons suffering from Diabetes, Cancer, etc.

What are the signs and symptoms of Legionellosis?

Legionellosis symptoms include:

• Muscle aches and pains,
• Headaches,
• Fatigue,
• Loss of appetite,
• Diarrhea,
• Coughing,
• High fever, and
• Chills.

Chest X-rays are almost always indicative of pneumonia in case of Legionnaires' disease.

How long before the above symptoms occur?

Even thought it often takes between 2 to 10 days for Legionnaires' disease to develop, most often the above symptoms are present within 5 to 6 days of the exposure. For Pontiac fever, however, it may only take between few hours to up to two days for the above symptoms to occur.

How is Ligionellois diagnosed?

The diagnosis of legionellosis requires special tests that are not routinely performed on patients suffering from fever or pneumonia. Therefore, a physician must have a reason to suspect the possibility of legionellosis in order for her to order these specific tests.

Even though several types of tests are available for legionellois, most tests are designed to detect the Legionella bacteria in sputum, and to find Legionella antigens in patient's urine samples. Usually the antibody levels to Legionella in two blood samples obtained over 3 to 6 weeks are then compared.

What is the treatment for Legionellosis?

No treatment is necesary for Pontiac fever. In case of Legionnaires’ disease, antibiotics (erythromycin) are usually prescribed.

How to prevent Legionellosis?

Preventing the growth and spread of Legionella organisms is the only effective way to prevent this disease. Better designs and maintenance of cooling towers and plumbing systems, therefore, are crucial to preventing the outbreaks of legionellosis.

Don't forget to check out Lung Disease News section of this website for the latest Legionellosis/Legionnaires' disease Treatment News, and our Lung Disease Articles Library for the latest Legionellosis/Legionnaires' disease related Articles.

Note: Consult a qualified medical practitioner if you suspect lung disease. Information published at this mesothelioma lung disease asbestos cancer forum - or most other websites for that matter - should not be relied upon for health decisions. The information presented on this web site is not intended as a substitute for medical care, medical, legal, or professional advise. Please talk with your healthcare provider for all your health concerns.