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What is Legionnaires’ Disease?

Legionnaires’ disease is a severe form of pneumonia —lung inflammation usually caused by infection, typically by the bacterium Legionella, which has also been linked to Pontiac Fever. It is collectively known as legionellosis. The disease is contracted from Legionella bacteria that can be found in the water systems of public facilities like hospitals, nursing homes, and hotels. The Centers for Disease Control and Prevention (CDC) have stated that the number of reported cases in the U.S. has increased nearly nine-fold since 2000.

The disease can be contracted from breathing small droplets of water in the air containing Legionella. Older adults, smokers, and people with weakened immune systems are particularly susceptible to legionnaires disease.

Where is it commonly found?

          • Hot tubs and whirlpools not drained between uses
          • Grocery store mist machines
          • Cooling towers in air conditioning systems
          • Decorative fountains
          • Medical devices (CPAP machines)
          • Shower heads and stagnant plumbing
          • Water systems in hotels, hospitals, and nursing homes
          • Ice machines

How can Legionella outbreaks be prevented?

Organizations such as the CMS and ASHRAE have created guidelines and standards for reducing the risk of Legionella infection. The CMS has facility requirements for minimizing Legionella risk in facility water systems while ASHRAE Standard 188 also establishes minimum Legionellosis risk management guidelines. 

What is Pontiac Fever?

Pontiac fever is a milder, non-pneumonic form of Legionnaires’ disease, both of which are caused by the bacterium Legionella pneumophila. Pontiac fever is characterized by flu-like symptoms, including fever, headache, muscle aches, and chills. Unlike Legionnaires’ disease, Pontiac fever does not involve pneumonia, and individuals typically recover without the need for specific medical treatment.

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