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Environmental and Workplace Health

Legionnaires' Disease

Legionnaires' disease is a rare and sometimes severe type of pneumonia caused by a bacteria called Legionelle pneumophila, which is found in water sources. People become infected by breathing in mist or steam that contains the bacteria. Outbreaks and individual cases have been traced to a number of specific water sources including the following:

  • Cooling towers for large air-conditioning systems (e.g., in hotels, hospitals);
  • Humidifiers;
  • Water distribution systems (e.g., showers);
  • Whirlpool spas and hot tubs; and
  • Respiratory therapy devices in hospitals.

You can prevent Legionnaires' disease in your own home by properly maintaining all mist-producing devices such as shower heads, hot tubs, whirlpools and humidifiers. Make sure you clean and disinfect these devices regularly according to the manufacturers' directions.

Health Canada Resources

For additional information about Legionnaires' disease, you can contact the Next link will take you to another Web site Public Health Agency of Canada.