Nina Pham was identified as the Dallas nurse who contacted Ebola, Yahoo News reported Monday. She cared for Thomas Eric Duncan, the first person to die from the fatal virus in the U.S.

The hospital didn't reveal the nurse’s name, but Yahoo News said they identified her through public records and a state-nursing database. Her family later confirmed her identification to local Dallas ABC News affiliate WFAA.

Pham, 26, is a critical care nurse at Texas Health Presbyterian Dallas and one of the 50 people to take care of Duncan before he died last Wednesday. She is currently in stable condition after being isolated since Friday, Yahoo News reported. The Centers for Disease Control and Prevention confirmed the case Sunday. It is the first time the virus has been transmitted in the U.S.

She was diagnosed with Ebola after she reported a fever, WFAA wrote.

CDC director Dr. Thomas Frieden said an unidentified person who had close contact with Pham is in isolation, but has not become ill. "If this one individual was infected and we don't know how -- within the isolation unit -- then it is possible that other individuals could have been infected as well," Frieden said during a press conference Monday. "We consider them to be at risk and we are doing an in-depth review and investigation."

Frieden apologized for earlier remarks he made about Pham contracting the virus through a possible breach of safety protocols. "Some interpreted that as finding fault with the hospital or the health care worker, and I'm sorry if that was the impression given, that was certainly not my intention," Frieden said. "What we need to do, is all take responsibility for improving the safety of those on the front lines. I feel awful that a health care worker became infected in the care of an Ebola patient. She was there trying to help the first patient survive."

Frieden explained he was not sure how Pham was infected. "The existence of the first case of Ebola spread in the U.S. changes some things and it doesn't change some things," he said, according to USA Today. "It doesn't change the fact that we know how Ebola spreads. It doesn't change the fact that it's possible to treat Ebola safely. But it does change substantially how we approach it."

At least 4,000 people have died in the Ebola outbreak, which has widely affected the West African nations of Liberia, Guinea and Sierra Leone. The CDC continues to monitor 48 other people, 10 who had confirmed contact with Duncan, WFAA wrote.

Follow me on Twitter @mariamzzarella