Water Sources | Legionella.org

What have been the water sources for Legionnaires’ disease?

The major source is water distribution systems of large
buildings, including hotels and hospitals. Cooling towers have long
been thought to be a major source for Legionella, but new
data suggest that this is an overemphasized mode of transmission.
Other sources include mist machines, humidifiers, whirlpool spas,
and hot springs. Air conditioners are not a source for
Legionnaires’ disease. They were suspected to be the source in the
original American Legion outbreak in a Philadelphia hotel, but new
data now suggests that the water in the hotel was the actual
culprit. Read more
about water sources.