Second Ebola Nurse Violated Guidelines By Flying on Commercial Jet Nurse flew Frontier Airlines day before arriving at hospital with fever.

 -- A second Texas nurse who has tested positive for Ebola violated infection control guidelines by flying on a commercial jetliner from Cleveland to Dallas the night before she arrived at the hospital with a fever, officials said today.

The nurse, who has been identified as Amber Vinson, 29, was part of the team at Texas Health Presbyterian Hospital who took care of Thomas Eric Duncan, a Liberian man who died of Ebola on Oct. 8.

She is the second member of the hospital staff to contract the virus and a Dallas official warned today that additional cases among the hospital's health care workers are a "very real possibility."

Vinson was one of the nurses who was very involved with the care for Ebola patient Duncan, who died of Ebola at the Dallas hospital. She drew his blood, inserted catheters, and dealt with his bodily fluids, according to Duncan's medical records obtained by the Associated Press.

"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," said Dr. Thomas Frieden, director of the Centers for Disease Control and Prevention. "From this moment forward, we will ensure that no individual monitored for exposure undergoes travel in any way other than controlled movement," he said referring to non-public transportation, such as a personal car or chartered flight.

Vinson reported a slightly elevated temperature of 99.5 degrees to the CDC prior to flying to Ohio, ABC News confirmed. According to a CDC official, since she didn't meet the 100.4 degree threshold for a fever, she wasn't "told she couldn't fly."

Vinson has since been transferred from Dallas to Emory University Hospital in Atlanta, Georgia, which has successfully treated other Ebola patients.

President Obama was supposed to visit New Jersey and Connecticut today, but he canceled the trip to hold a cabinet meeting in the White House to coordinate a response to the Ebola outbreak.

The CDC is reaching out to the 132 passengers who flew with the woman on Frontier Airlines Flight 1143 on Monday evening, landing in Dallas at 8:16 p.m. The health care worker had no symptoms during the flight, the CDC said, but officials are identifying and notifying passengers because she arrived at the hospital with a fever the following morning.

Among those passengers was a group of employees - mostly nurses - from Cleveland Clinic and MetroHealth, the hospitals said Wednesday. They were returning from a conference in Texas.

Those employees are on paid leave as an “extra precautionary step” while their health is monitored daily, the hospitals said.

Once the Frontier Airlines flight landed in Dallas, the plane was cleaned for the evening before flying out the next day, according to a statement from Frontier Airlines, which said its procedures are "consistent with CDC guidelines." It was cleaned again in Cleveland the following night.

Both nurses who became infected had contact with Duncan in his first days in the Dallas hospital -- on Sept. 28, 29 and 30 -- when he was having "substantial amounts" of vomiting and had diarrhea, according to Frieden. He said officials will be assessing other health workers who had extensive contact with Duncan on these days.

“The fight against Ebola in Dallas is a two-front fight now,” Dallas County Judge Clay Jenkins said, speaking at a morning press conference.

Authorities said they are now tracking 75 people following the second hospital worker’s diagnosis. The unidentified health care worker reported a fever Tuesday and was isolated at the hospital, authorities said.

The preliminary Ebola test was run late Tuesday at the state public health laboratory in Austin, and results were received at about midnight, authorities said. The Centers for Disease Control and Prevention has begun confirmation testing.

The woman was put into isolation within 90 minutes, and she is dealing with her diagnosis "with grit and grace," Jenkins said.

Authorities said this may not be the last case to be found among the hospital’s staff.

"We are preparing contingencies for more and that is a very real possibility," Jenkins said.

Dallas Mayor Mike Rawlings also suggested additional people may get sick.

"It may get worse before it gets better, but it will get better,” the mayor said.

Dr. Daniel Varga of Texas Health Resources defended practices at the hospital, which has faced criticism amid the Ebola diagnoses.

“It’s clear there was an exposure somewhere, sometime in our treatment of Duncan. Let’s be clear we’re a hospital that serves this community extremely well,” Varga said at the press conference.

“We’re the first to diagnose and treat this insidious disease that has attacked two of our own.”

City workers went to the neighborhood of the second patient early this morning to knock on doors to alert people to the news and to be alert to possible symptoms. They handed out flyers and later began robo calls to the area, Varga said.

Rawlings said the community remains vigilant.

“The only way that we are going to beat this is person by person, moment by moment, detail by detail,” Rawlings said. "While Dallas is anxious about this … We are not fearful.”

Health officials interviewed the patient, hoping to track down any contacts or potential exposures in the community, the CDC said in a statement.

"While this is troubling news for the patient, the patient’s family and colleagues and the greater Dallas community, the CDC and the Texas Department of State Health Services remain confident that wider spread in the community can be prevented with proper public health measures including ongoing contact tracing, health monitoring among those known to have been in contact with the index patient and immediate isolations if symptoms develop," the CDC said in a statement.

Authorities visited the patient's apartment this morning to begin decontamination efforts.

The workers donned hazmat suits, trying to protect themselves from exposure.

The new diagnosis comes days after nurse Nina Pham, 26, who also treated Duncan, was diagnosed with Ebola. Duncan was diagnosed with Ebola Sept. 30 and died Oct. 8.

Burwell admitted that the reasons for the hospital workers becoming infected aren't clear.

"Those are people that came in contact because we don't understand exactly how the breach in protocol occurred," Burwell told ABC News today. "We are taking the precaution of making sure that anyone within that treatment phase will be tracked and monitored in a more serious way."

Ebola has killed more than 4,000 people, mostly in the West African countries of Liberia, Sierra Leone and Guinea, according to recent figures by the World Health Organization.

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