(Bloomberg) — The second health-care worker diagnosed with Ebola in Texas flew from Cleveland to Dallas hours before she reported her symptoms, U.S. officials said.

The caregiver caught the deadly virus while treating patient Thomas Eric Duncan at Texas Health Presbyterian Hospital in Dallas earlier this month. She flew to Dallas on Frontier Airlines flight 1143 the night of Oct. 13, according to a e- mailed statement by the U.S. Centers for Disease Control and Prevention. She then reported symptoms the next morning.

“Because of the proximity in time between the evening flight and first report of illness the following morning, CDC is reaching out to passengers,” the agency said. The plane had 132 passengers, the CDC said.

The flight was the last of the day for the aircraft, which returned to service the next day after receiving “a thorough cleaning per our normal procedures,” Frontier Airlines said in a statement. It has since been taken out of service.

The health worker originally traveled to Cleveland from Dallas on Frontier flight 1142 on Oct. 10, the airline said. The CDC didn’t say that it was contacting people on that flight. Ebola is only contagious while a person is symptomatic.

Frontier is owned by Indigo Partners LLC, a unit of private equity and asset management firm Carlyle Group LP.

This is the second health-care worker infected with Ebola while caring for Duncan, a Liberian visitor to the U.S. who died at the hospital on Oct. 8.

Allowed to fly?

Sana Syed, a spokeswoman for the city of Dallas, said she didn’t know why the caregiver was allowed to fly. She said news accounts this morning were the first the city has heard about it.

“That’s a CDC question,” Syed said in a telephone interview. “We’re trying to figure that out for ourselves.”

Thomas Frieden, director of the CDC, said while the health worker was self-monitoring for potential symptoms after caring for Duncan, “because at that point she was in a group of individuals known to have exposure to Ebola, she should not have traveled on a commercial airline.”

Frieden said the new patient didn’t have a fever, nausea or vomiting on the plane from Cleveland to Dallas, suggesting “that the risk to any around that individual would have been extremely low.”

Frontier reaction

Frontier Airlines has now taken the Airbus A320 used on the Oct. 13 flight out of service, said Todd Lehmacher, a spokesman for the Denver-based airline. The carrier notified unions representing its workers before issuing a joint statement with the CDC on flights taken by the nurse.

The crew for Flight 1143 has been suspended from duty with pay, Lehmacher said. Two pilots and four flight attendants worked the flight.

“Though there is very little risk to our crewmembers per what the CDC is telling us, we made the decision out of an abundance of caution as we want to ensure both our employees and customers are kept safe,” he said. “Their well- being is our primary concern.”

The Association of Flight Attendants “is working with management and CDC officials to ensure that the health of Frontier flight attendants was not compromised at any point,” said Corey Caldwell, a spokeswoman for the union’s national office. “AFA will continue to press that crew members are regularly monitored and provided with any additional resources that may be required.”

Systemic problem?

Angie Reef, president of the AFA at Frontier, and Mike Haffling, vice president of the Frontier Airline Pilots Association, declined to comment immediately. The unions represent 1,000 flight attendants and about 650 pilots at Frontier.

Asked at a briefing today about the hospital’s performance, Daniel Varga, the chief clinical officer for the hospital group, said “I don’t think we have a systemic institutional problem.”

Some Texas Health Presbyterian workers are included in the 48 people initially being monitored by local health officials after possibly having contact with Duncan before he was isolated, according to Dave Daigle, a Dallas-based CDC spokesman who is part of the Ebola contact-tracing efforts. The new care giver admitted to the hospital wasn’t part of that original group. Daigle declined to give further details on why the health-care worker was allowed to travel or whether other health workers are currently undergoing testing for the virus.

Hospital criticized

U.S. state and local health workers are attempting to combat any spread of Ebola in the U.S. after the hospital where Duncan was treated has been criticized for not having initially done enough to protect the people taking care of him.

National Nurses United, a labor union, said the hospital left Duncan for hours in an area with other patients, supplied safety suits with exposed necks, forcing nurses to use medical tape to cover their skin, played down the need for more protective face masks, and sent Duncan’s lab specimens through the system without being specially sealed.

The latest health worker infected reported a fever yesterday and was immediately isolated at the hospital, the Texas Department of State Health Services said in a statement today. A preliminary Ebola test was run late yesterday at the state public health laboratory in Austin, and results were received at about midnight.

–With assistance from Kelly Gilblom in New York and Darrell Preston in Dallas.