What is Legionnaires' disease?

Legionnaires’ disease is an uncommon infection of the lungs (pneumonia) caused by Legionella bacteria. The bacteria are commonly found in the environment, particularly water and soil.

Infection occurs 2-10 days after a person breathes in the bacteria in contaminated water vapours or dust.

Legionnaires' disease fact sheet

Legionella control

The Public Health Act 2010 and the Public Health Regulation 2012 control various man-made environments and systems which are conducive to the growth of Legionella organisms and which are capable of transmitting Legionnaires' disease. These regulated systems include:

  • water cooling systems
  • hot water systems
  • warm water systems
  • air handling systems.
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Outbreak measures

NSW Health’s public health units actively investigate all cases of Legionnaires’ disease.

For information on particular outbreaks, see Alerts, NSW Health media releases or the website of your local health district.

Frequently asked questions

Safe gardening

Legionella longbeachae is commonly found in the soil and potting mix. Reduce exposure to potting mix dust by following the manufacturers' warning present on potting mix labels, including:

  • wet down the potting mix to reduce the dust.
  • wear gloves and a protective mask (N95/P2 respirator) when using potting mix.
  • wash your hands after handling potting mix or soil, and before eating, drinking or smoking.
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Who is at risk?

Legionnaires disease most often affects middle-aged and older people, particularly those who smoke or who have chronic lung disease.

People whose immune systems are suppressed by medications or diseases such as cancer, kidney failure, diabetes or HIV/AIDS, are also at increased risk of Legionnaires' disease.

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Current as at: Tuesday 31 May 2022
Contact page owner: One Health