A fifth patient at University of Washington Medical Center in Seattle has contracted a Legionella bacteria infection, days after the hospital said its Legionnaires' disease outbreak had likely been contained.
The newly diagnosed patient had been hospitalized twice in the medical center's Cascade Tower where the outbreak occurred. After an investigation, officials now believe the patient contracted the infection either in the community or during the hospitalization earlier in September, before the hospital instituted water restrictions.
UW Medical Center instituted water precautions Sept. 13 and performed hyper-chlorination of the tower's water system Sept. 20 to eradicate the bacteria from the system after four patients contracted Legionnaires' disease. An investigation had revealed Legionella bacteria were dwelling in sinks, ice machines and operating room devices in the hospital's Cascade Tower.
Because the fifth infection is believed to have taken place before water precautions were lifted Sept. 20, the water restrictions will not be reinstituted in the Cascade Tower.
UW Medical Center is still working with the CDC and Public Health-Seattle & King County on the outbreak, and the hospital is testing samples from patients who had tests ordered for a lung infection for Legionella.
Legionella bacteria can cause Legionnaires' disease, a type of pneumonia that can be deadly. Two of the five infected UW Medical Center patients have died.
Editor's note: This story was updated Sept. 28 at 8:45 CT to reflect new information from UW Medical Center. Previously, officials did not know if the fifth patient became infected before or after the hospital instituted water precautions and cleaned the water system.