UPMC Presbyterian's transplant program reopened Sept. 27 after an on-site investigation by the federal Centers for Disease Control and Prevention and the Pennsylvania Department of Health failed to find the mold linked to patient deaths, according to an article on the TribLive website.
Dr. Steven Shapiro, the Pittsburgh hospital system's chief medical officer, said investigators may never determine a specific source.
He said investigators discounted the demolition of the Children's Hospital building attached to UPMC as an origin. He also said mold found in toilets and a wall of the ICU did not match the type that infected the patients.
The health department asked UPMC to implement corrective action.
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