The disease is caused by Legionella bacteria which are widespread in our environment. They are found in natural water bodies such as rivers, lakes, creeks and hot springs. The bacteria are also found in spas, potting mix, warm water systems and artificial systems that use water for cooling, heating or industrial processes, such as cooling towers.
Catching the disease
A person may catch Legionnaires' disease by breathing in fine droplets of water that contain the bacteria. You cannot catch it from another person or by drinking contaminated water.
Some people are at greater risk of infection than others
Although this is a common bacteria in the environment, only a few people who come in contact with the bacteria become infected. Some people are at greater risk, such as:
The physical effects
- Men over 50 years of age
- People with chronic illness
- People with medical conditions that impair their immune system.
The symptoms of Legionnaires' disease usually begin to appear within six days of being exposed to the bacteria. Early symptoms are like the flu and include:
- Muscle aches and pains
- A dry cough and shortness of breath.
Sometimes other systems in the body are affected. This can cause:
Diagnosing and treating the disease
- Mental confusion
- Kidney failure.
If you have the symptoms described above, see your doctor. Special tests are needed to diagnose the disease. A urine test or blood samples taken three to six weeks apart will usually diagnose Legionnaires' disease.
The tests for Legionnaires’ disease are not screening tests - there is no value in being tested if you are not unwell.
The infection can be treated with antibiotics.
Preventing Legionnaires' disease
There is no vaccine to prevent the disease. However, the growth of the bacteria in spas and cooling towers can be controlled. You can also take care to avoid exposure to Legionella bacteria from other sources, such as potting mix (see below).
Maintenance and treatment of artificial systems
A number of different regulations set out how to maintain and treat cooling towers, warm water systems and public spas to prevent the Legionella bacteria growing. For further information visit the Legionella Risk Management
Take care with potting mix
In recent years some cases of Legionnaires' disease have been linked to the use of potting mix. When using potting mix you should:
Where to get help
- Always wear gloves to avoid transferring the potting mix from your hand to your mouth.
- Open the bag carefully to avoid breathing in the dust.
- Wet the contents of the bag to prevent dust.
- Wash your hands after using potting mix.
Things to remember
- Your doctor
- Your local hospital
- Your local council
- Your nearest Department of Human Services office.
- Human Services, Infectious Diseases Unit, Tel. (03) 9637 4126.
Infections - bacterial and viral
- Legionnaires’ disease is a rare form of pneumonia.
- Not everyone who comes into contact with the bacteria is affected.
- If you have the symptoms, contact your doctor immediately.
- Early treatment can prevent the disease from becoming severe.
- Always take care when using potting mix.
This page has been sourced from the Better Health Channel and produced in consultation with, and approved by the following sponsor. The sponsor logo links to more information relevant to this article.
Print a fact sheet
To print a fact sheet, open the PDF (Portable Document Format) version of this article
. The PDF has been prepared by the Better Health Channel
. You will need Adobe Acrobat or a recent-version browser to display the file. You can download Adobe Acrobat from the Adobe website
Legionnaires' disease fact sheet in PDF format.
Article publication date: 25/05/1999
Last reviewed: 30/07/2004
This article, like all health articles on the Disability Online, is sourced from Better Health Channel and has passed through a rigorous and exhaustive approval process. It is also regularly updated. For more information see Better Health Channel quality assurance
Return to top