A top federal health official said Monday that the diagnosis of a Dallas nurse with Ebola—the first case to be transmitted in the U.S.—"does change substantially how we approach" the virus.
"We have to rethink the way we address Ebola infection control because even a single infection is unacceptable," said Dr. Thomas Frieden, director of the Centers for Disease and Control, during a briefing from Washington, D.C.
The nurse, based at the Texas Health Presbyterian Hospital where Liberian national Thomas Eric Duncan eventually died from the virus last week, reported a low grade fever Friday night and was isolated.
A family friend who spoke with NBC News later identified the nurse as 26-year-old Nina Pham—Frieden did not name her during his briefing.
"I feel awful that a health-care worker became infected in the care of an Ebola patient," Frieden said "She was there trying to help the first patient survive and now she has become infected. All of us have to work together to do whatever is possible to reduce the risk that any other health care worker becomes infected."
Frieden said a CDC team and the hospital are investigating how Pham contracted the virus from Duncan, as well as working to interview and monitor the "large" number of health-care workers that may also have had contact with Duncan.
"We need to consider the possibility that there could be additional cases," Frieden said, several hours before President Barack Obama was scheduled to be briefed about the ongoing response to Ebola by his administration.
Frieden said the team is also evaluating how to make changes in the way staff members are treating such patients and how they can protect themselves to avoid future transmissions. Workers are being watched as they go in and out of the isolation unit—to see how they put on and remove their protective gear—where the infected nurse is being treated.
Frieden also said the team is "looking at the protective equipment that is used," and is examining the possibility of spraying workers down with a substance that could neutralize the deadly virus.
He said officials would "double-down" on training, outreach, education and assistance for health-care systems and workers nationwide to increase awareness of Ebola and know how to rapidly response to suspected cases. In particular, he noted, patients should be isolated immediately if they have a fever and if they been in West Africa in the past 21 days.
"Stopping Ebola is hard," he said. "We're working to make it safer and easier."