Legionella discovered in UW Medical Center water supply after 2 patients die

SEATTLE -- Two patients who died have tested positive for Legionnaires' Disease, and water samples from the Cascade Tower at UW Medical Center have tested positive for Legionella, public health officials said Wednesday.

According to Public Health Seattle-King County, a patient hospitalized with Legionella died from the infection earlier this month. Legionella was said to be a "contributing factor" in the death.

Officials said another patient in their cardiac care unit also tested positive for Legionella. That person died Aug. 27, but the connection to Legionella wasn't discovered until an autopsy was performed.

UW Medical Center told public health officials that environmental samples in the water supply in the Cascade Tower, where the cardiac care unit is located, tested positive for Legionella. UW said they took "immediate steps to reduce the risk where Legionella has been found in the water."

Public health officials released this statement:

Public Health’s role has been to assist with the assessment of the extent of the problem, help identify the source of Legionella, continue to monitor for new cases in collaboration with UWMC, and provide recommendations on control measures to reduce ongoing risk. In this capacity, we have been consulting with our partners at CDC.

We can’t predict if additional cases will be identified at UWMC, but it is possible because of exposures that happened at the hospital before the Legionella was identified and protective actions were put into place.

However, for most people, the risk of Legionella is very low. All three patients who developed Legionnaire’s disease were at high risk for this infection.

Here is more information on Legionella:

Who is at higher risk of getting sick?

Most healthy people do not get sick after being exposed to Legionella. People at increased risk of getting sick are:

  • People 50 years or older
  • Current or former smokers
  • People with a chronic lung disease (like chronic obstructive pulmonary disease or emphysema)
  • People with a weak immune system from diseases like cancer, diabetes, or kidney failure
  • People who take medications that suppress (weaken) the immune system (like after a transplant operation or chemotherapy)

Public Health – Seattle & King County’s role in the investigation

Investigation of infectious diseases is part of the essential work of Public Health – Seattle & King County. In this incident, our role is to assist with the investigation and assessment of the extent of the problem, identification of a source of the legionella, and eliminate ongoing risk at the healthcare facility. We also provide information to the public about Legionnaire’s disease and on the findings and status of our investigation.

Learn more on Legionella from the CDC.