2 patient cases of Legionella reported

Two patients at University of Washington Medical Center – Montlake were recently treated for Legionella. These cases were identified several months apart but may have been exposed during inpatient stays at UW Medical Center. Both patients have since been discharged from the hospital and are in satisfactory condition. 

No additional cases of Legionella have been identified with exposure at UW Medical Center – Montlake at this time.  (See January 2025 post describing two previous cases.) To date, all water testing has been negative for these Legionella species. We continue to implement recommended water quality testing and monitoring. 

UW Medicine worked closely with Public Health – Seattle & King County, the Washington State Department of Health, and the Centers for Disease Control and Prevention to review these cases and continue to work with experts in water treatment.

UW Medical Center – Montlake has a robust water-management program. It includes testing and monitoring water temperature, chlorine levels and the presence of water-borne bacteria. 

Legionella is present in the natural environment, so it can be difficult to determine the initial source of infections.  Legionella is a common water-borne bacteria, and most healthy people who are exposed do not get sick. People at increased risk of getting sick include anyone with certain underlying health conditions such as chronic lung disease or a weak immune system. 

Patients with concerns should call their local healthcare provider. For more information about Legionella, please visit the CDC website.

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