Federal health officials said Wednesday that a second Dallas health-care worker who tested positive for Ebola "should not have traveled on a commercial flight" with 132 other passengers from Cleveland to Dallas just a day before being diagnosed. All of those passengers on that Frontier Airlines flight Monday were asked to immediately contact the U.S. Centers for Disease Control for possible monitoring, as officials also announced that the new patient will be transported later Wednesday to a hospital in Atlanta for treatment. The new patient was identified by Cleveland's public health director as Amber Vinson, a 29-year-old nurse. The director also said Vinson had traveled to Cleveland from Dallas on Oct. 8—the same day that that the patient who infected her, Thomas Eric Duncan, died in Texas Health Presbyterian Hospital. Vinson traveled to Ohio to prepare for her upcoming wedding and to visit her mom and fiancé, the official said. Medical records obtained by the Associated Press show that Vinson's extensive care for Duncan included inserting catheters, drawing blood and dealing with his bodily fluids. Officials are monitoring three people Vinson had contact with before she was isolated Tuesday. Health officials in Summit County, Ohio said, "Family members are cooperative and self-quarantining in their home" Read MoreAirline stocks down after Ebola patient update

CDC Director Dr. Thomas Frieden said Vinson should not have take any public transportation including the flight because she had had contact with Duncan at her hospital, and because her temperature was a slightly elevated 99.5 degrees before she boarded Monday's flight from Cleveland. However, Dallas County Judge Clay Jenkins later said that CDC never told Texas Health Presbyterian to instruct its staff who had dealt with Duncan not to travel. Vinson went to the hospital with a low-grade fever on Tuesday morning, according to the CDC. She is the second health-care worker at Texas Health Presbyterian Hospital in Dallas to be diagnosed with Ebola after having cared for the Liberian national Duncan. The other current patient there was a nurse for Duncan, 26-year-old Nina Pham, who is stable condition. Frieden said that the risk of the woman having infected another person on the flight Monday is "extremely low" because of the difficulty in transmitting Ebola, and because she had no symptoms or fever. Vinson "will be transported" to Emory University hospital in Atlanta from Dallas later Wednesday "as a result of a clinical decision," said U.S. Health and Human Services Secretary Sylvia Matthews Burwell. Vinson was not named by Burwell, Frieden or health officials in Texas when they discussed her case.

More cases 'a very real possibility'

Emory's isolation unit recently cared for two prior Ebola patients, Dr. Kent Brantly and Nancy Writebol, who have recovered from the virus, and is continuing to treat a third, unidentified patient. Emory also is sending two nurses to Texas Health Presbyterian to assist in Pham's treatment. Kent State University in Ohio said Vinson has three relatives who work at the university, but also said she did not visit the campus during her recent trip to her family's home in Summit County, Ohio. Kent State's director of health services, Dr. Angela DeJulius, said "Out of an abundance of caution, we're asking the patient's family members to remain off campus for the next 21 days and self-monitor per CDC protocol." Read MoreCDC says regrets not sending big Ebola team

Neither the three people who had contact with Vinson, nor more than 120 others who had contact with Duncan will be allowed to travel on commercial flights or public transportation until they clear the incubation deadline for the virus, Frieden said. In response to dramatic developments, President Barack Obama canceled a planned election-season trip Wednesday to New Jersey and Connecticut. Instead, administration officials said, he will convene an afternoon meeting at the White House with agencies coordinating the government's response to the outbreak.

Officials also warned that additional cases of the deadly virus at the Dallas hospital where the woman worked are "a very real possibility."

"We have contingencies for more," Judge Jenkins said during a morning briefing on Vinson's diagnosis. Jenkins said Vinson was isolated within 90 minutes of reporting a fever Tuesday. She is the third person diagnosed in the U.S. with Ebola, which is currently epidemic in three West African countries. The CDC hours later revealed that Vinson had flown on Monday on Frontier Airlines Flight 1143 from Cleveland to Dallas/Fort Worth. The CDC asked all passengers aboard that flight to call 1-800-232-4636. Frontier Airlines said passengers who also traveled with the woman on Flight 1142 from Dallas/Fort Worth to Cleveland should contact CDC as well. Frontier said that flight to Cleveland occurred last Friday, but Cleveland officials said it occurred Oct. 8. "Individuals who are determined to be at any potential risk will be actively monitored," the CDC said in a statement. It said the woman exhibited no symptoms aboard the flight on Monday evening. The disease can be spread only by contact with bodily fluids and when symptoms appear, and not by casual contact, the CDC has said.

Frontier Airlines said the aircraft used for Flight 1143 remained grounded overnight from Monday and received a thorough cleaning, as is normal. The aircraft was cleaned again in Cleveland on Tuesday night, the airline said.

The Frontier plane has been decontaminated twice and will go on a a scheduled flight to Denver on Wednesday, according to Cleveland officials. Vinson and Pham's employer, Texas Health Presbyterian, is facing renewed criticism for its handling of Duncan's case. Read MoreTexas college bans students from 'Ebola countries'

Texas Health didn't initially admit the Liberian national Duncan for treatment Sept. 25 despite knowing he had a high fever and had recently traveled from West Africa, center of the largest Ebola outbreak on record. Duncan was admitted three days later after becoming more seriously ill. Vinson and Pham were among 77 people who were involved in treating Duncan or handling his blood. All were placed on a monitoring list, but only after Pham had been diagnosed with Ebola. They join 48 people who had or may have had contact with Duncan before he was admitted to the hospital.

"Health officials have interviewed the latest patient to quickly identify any contacts or potential exposures, and those people will be monitored," the Texas Department of Health said in a statement. "The type of monitoring depends on the nature of their interactions and the potential they were exposed to the virus." Read MoreEbola: Is the world ready for the next pandem

As with Pham's case, it is not known precisely how Vinson became infected while caring for Duncan. But Frieden said both women "had extensive contact" with Duncan in the initial days of his stay at Texas Health, a time when he was suffering from intense vomiting and diarrhea. During that same time, Frieden said, "a variety of forms of personal protective equipment were used." Jenkins, the Dallas County judge, called the new case "a gut shot" to the staff at Texas Heath, "because this is one of their own." He said more cases there are "a very real possibility." Read MoreDon't fall victim to these Ebola scams

Jenkins called Vinson, without using her name, "a heroic person, a person who is dedicating her life to serving others." "And we hope and pray that, like Nina, she will get on a good track."

CDC reviewing treatment protocols

Early Wednesday, officials made reverse 911 calls to neighbors of Vinson's in Dallas. The common areas outside her apartment were cleaned, and the inside of her unit was set to be cleaned later in the day.

Vinson lives alone, with no pets, officials said.

Frontier Airlines planes. Robert Alexander | Getty Images

The latest case came to light just hours after CDC Director Frieden said he regretted not having immediately sent a more "robust" CDC team Texas Health after Duncan was admitted with Ebola in late September. Read MoreCDC adds 76 to Ebola watchlist, regrets not sending big team

Frieden said such a step "might have prevented" Pham's infection. Her diagnosis led the CDC to "rethink" the way it tries to control Ebola from spreading to caregivers, said Frieden, who since has dispatched a specialized infection-control team to Texas to complement an existing CDC squad.

Officials are reviewing and revising the protocols for treatment of the two women at the hospital. Among other things, Frieden has suggested that health-care workers may have been using too many layers of protective garb, which can present an opportunity for a mistake when they are removed after interacting with a patient, as can the use of tape to hold down openings for hands in that gear. He also said officials have recommended that fewer caregivers go in and out of the rooms containing an Ebola patient.

Nurses cite confusion, lack of training