An autopsy has confirmed that at least one patient in New York-Presbyterian Hospital/Columbia University Medical Center died of Legionnaire's disease, the hospital said Tuesday.
"We view this matter very seriously and are taking all necessary measures to insure the safety of our patients," the hospital said in a statement.
Last week, the hospital said four patients had been treated for Legionnaire's disease last month and two of them died. It said an autopsy "concluded that Legionella pneumonia was a primary factor" in one of the patient deaths.
The second patient's case has been referred to the medical examiner's office, which has yet to determine a cause of death.
The hospital initially said Legionella bacteria were identified in the water supply of its Milstein Hospital Building. On Tuesday, it said further testing detected Legionella bacteria in the Greenberg Pavilion at the hospital's campus on the East Side of Manhattan.
Bottled water was being distributed to patients at both sites, the hospital said.