In caring for Thomas Duncan, the first patient diagnosed with Ebola in the United States, hospital workers violated guidelines from the Centers for Disease Control and Prevention concerning protective gear and travel, potentially putting more individuals at risk of infection.

The nurse who was most recently diagnosed with Ebola traveled on a small Frontier Airlines flight from Cleveland to Dallas with 132 passengers on Monday, prompting health officials to begin reaching out to every passenger and crew member on the airplane. Her temperature was elevated before she traveled, but at 99.5 degrees, it did not meet the threshold for isolation. She began exhibiting Ebola symptoms the day she arrived in Dallas and was admitted to Texas Health Presbyterian Hospital, where she works.

The nurse "should not have traveled on a commercial airline" after being with Duncan, CDC Director Thomas Frieden said Wednesday. Doing so was in violation of CDC's travel guidelines, which stipulate that anybody potentially exposed to the virus should travel under "controlled movement." Flying commercially—or getting on any public transportation at all—is not allowed under the agency's controlled-movement rules.

There were also multiple instances of misuse of protective gear by health care workers involved in Duncan's care, Frieden said. Early in Duncan's treatment, workers put on extra layers of protective equipment—sometimes up to three or four layers—or used tape to reinforce the gear. Frieden called the workers' anxiety "understandable," but said that layering protective gear can actually be more dangerous than using it normally. When you're wearing three or four gloves at once, "the risk of contamination during the process of taking gloves off gets much higher," he said.

The president asked the CDC to examine its guidelines and make sure they're followed, according to the White House. "It's not clear what protocols were in place and how those protocols were implemented," said Press Secretary Josh Earnest.

The nurse who traveled from Cleveland will be transferred from the Dallas hospital where she was diagnosed to Emory University Hospital in Atlanta, according to Health and Human Services Secretary Sylvia Mathews Burwell. Frieden described the nurse's condition as "ill but clinically stable."

This post has been updated to include information from the White House press briefing.

Correction: An earlier version of this post misstated the origin of the flight the nurse was on this week. It was Cleveland.

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