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

Legionnaires' (LEE-juh-nares) disease is caused by a type of bacterium called Legionella (LEE-juh-nell-a). The bacterium is named after a 1976 outbreak, during which some people who went to a Philadelphia convention of the American Legion suffered from a new type of pneumonia (lung infection) that became known as Legionnaires’ disease. A milder infection, also caused by Legionella, is called Pontiac fever. The term "legionellosis" (LEE-juh-nuh-low-sis) may be used to refer to either Legionnaires' disease or Pontiac fever.

image of man inspecting water system. Use CDC's new toolkit to help protect your water from Legionella. www.cdc.gov/legionella

Toolkit to Develop a Legionella Water Management Program

Get practical guidance on how to implement industry standards by identifying areas or devices in buildings where Legionella might grow or spread to people so that risk can be reduced through effective water management.

More

vital signs - 9 in 10 CDC investigations show almost all outbreaks were caused by problems preventable with more effective wagter management.June 2016 Vital Signs: Use water management programs in buildings to help prevent outbreaks…

More

Environmental Investigation Videos

clinicians taking water samplesCDC has developed six instructional videos on various environmental aspects of legionellosis outbreak investigations.

More

ELITE Program

CDC's ELITE Program

The Environmental Legionella Isolation Techniques Evaluation (ELITE) Program was created as a way for laboratories to test their Legionella isolation techniques against standardized samples.

More

Top