What is Legionnaire's Disease?

by Sharon Hopkins

A type of bacteria known as Legionella causes Legionnaire’s disease. In 1976, during a convention of the American Legion in Philadelphia, there was an outbreak of this type of lung infection and the name of the bacteria was thus given. Legionnaire’s disease continues to affect thousands of people every year with an increase in the number of cases during the summer or early fall. Nowadays, whenever a patient is diagnosed with pneumonia, he is checked for Legionnaire’s disease as well.


The symptoms of Legionnaire’s disease are similar to those of pneumonia, making the disease difficult to diagnose. Symptoms of Legionnaire’s disease include:

  • High feverM
  • Chills
  • Chronic cough
  • Muscle ache
  • Headache
  • Fatigue
  • Change of mental state i.e. confusion
  • Shortness of breath
  • Pain in the chest
  • Phlegm may become yellow or green or contain blood
  • Diarrhea / nausea / vomiting
  • Loss of appetite

These symptoms usually set in around two to fourteen days after exposure to the Legionella bacteria. In order to diagnose the disease, chest x-rays, blood tests and urine tests are necessary along with tests done on the sputum or phlegm to determine the type of bacterial infection. Legionnaire’s disease is a potentially life-threatening condition though in most cases with early detection and immediate medical treatment, recovery is possible. A milder type of lung infection caused by the same Legionella bacteria is known as Pontiac fever. Symptoms of Pontiac fever are similar to those of Legionnaire’s disease but milder and last for two to five days at the most.


Legionella bacteria are found in water, especially warm water found in hot tubs, saunas, spas, air conditioners, hot water tanks and plumbing systems of large buildings. The infection spreads when a person breathes in air that contains vapor or droplets of contaminated water. Legionella bacteria cannot spread from person to person or by drinking contaminated water. A Legionnaire’s outbreak occurs when two or more people from the same place or at the same time are diagnosed with the infection.

Certain people may fall into the high-risk category of developing Legionnaire’s disease such as older people, people with low immunity due to other diseases such as cancer or diabetes, smokers and those who already suffer from lung diseases such as asthma or emphysema.


Legionnaire’s disease is treated with antibiotics to kill the bacterial infection. Most doctors will prescribe drugs that contain antibiotics such as erythromycin or clarithromycin. These antibiotics are usually taken in tablet or capsule form though severe cases of the disease may require intravenous infusion of antibiotics. Depending on the severity of the symptoms, the typical course of antibiotics can last between seven days to three weeks.

If you already suffer from a chronic lung disease or weak immunity, hospitalization may be necessary to treat Legionnaire’s disease. Oxygen to help with severe breathing difficulties and IV fluids to prevent dehydration may be prescribed as well. If the pneumonia is very severe, assisted ventilation to support breathing may be needed. If not treated in time, Legionnaire’s disease can prove fatal. Other possible complications include respiratory failure, kidney failure, septic shock, bleeding problems and overwhelming sepsis.


The best way to prevent an outbreak of Legionnaire’s disease is to properly maintain all water systems. For example if you are a landlord or employer, you have to ensure that all water systems in your building or premise meet the relevant safety and health regulations. To prevent the Legionella bacteria from flourishing, water should be cooled to below 20ºC (68ºF) or heated to above 60ºC (140ºF) and should never be allowed to stagnate and become contaminated.


Warning: The reader of this article should exercise all precautionary measures while following instructions on the home remedies from this article. Avoid using any of these products if you are allergic to it. The responsibility lies with the reader and not with the site or the writer.
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