Skip directly to search Skip directly to A to Z list Skip directly to navigation Skip directly to page options Skip directly to site content


Español: Prevención

vital signs - 9 in 10 CDC investigations show almost all outbreaks were caused by problems preventable with more effective water management.

There are no vaccines that can prevent legionellosis.

Instead, the key to preventing legionellosis is making sure that the water systems in buildings are maintained in order to reduce the risk of growing and spreading Legionella. Examples of water systems that might spread Legionella include

  • Hot tubs
  • Hot water tanks and heaters
  • Large plumbing systems
  • Cooling towers (air-conditioning systems for large buildings)
  • Decorative fountains


Legionella and Hot Tubs

Home and car air-conditioning units do not use water to cool the air, so they are not a risk for Legionella growth.

Legionella grows best in warm water, like the water temperatures used in hot tubs. However, warm temperatures also make it hard to keep disinfectants, such as chlorine, at the levels needed to kill germs like Legionella. Disinfectant and other chemical levels in hot tubs should be checked regularly and hot tubs should be cleaned as recommended by the manufacturer. Learn how you can test the water before you use a hot tub and questions you should ask your hot tub operator to determine whether or not a hot tub has been properly maintained:


 Top of Page