A mix of worry and dismay gripped airline passengers on Wednesday at the Dallas airport where a nurse who treated a dying Liberian man arrived after boarding an Ohio-to-Texas flight with a slight fever and was later diagnosed with Ebola.

The woman, Amber Vinson, 29, was isolated after reporting a fever on Tuesday and became the second U.S. nurse to contract the virus this week after caring for Thomas Eric Duncan. He died of the disease on Oct. 8 and was the first patient diagnosed with the virus in the United States.

Passengers preparing to board a flight with Frontier Airlines, the airline Vinson flew with to and from Ohio, said they were upset with health officials for failing to expressly prohibit the nurse from flying, and with the nurse herself for potentially putting passengers at risk, however slight.

"I'm ashamed and disappointed at the hospital and others for allowing her to fly, and I'm sort of ticked off at her too," said Vicky Dahn, who was traveling to Utah with Frontier.

"I hope that this hasn't started to percolate from the hospital personnel out to other people," said Dahn, adding that she has a history of immune system trouble.

The hospital where Vinson and fellow infected nurse Nina Pham work, Texas Health Presbyterian, has been criticized for initially sending Duncan home without realizing he might possibly have been infected with Ebola and for not being adequately prepared for cases to crop up in Dallas after an outbreak that has killed nearly 4,500 people, mostly in West Africa.

Nurses associations have complained about a lack of training and protective equipment that left their necks exposed.

Passengers said public health officials should be more vigilant, while the Centers for Disease Control and Prevention asked all of the more than 130 other passengers who were on Frontier Flight 1143 on Monday to call a hotline. Vinson had traveled to Ohio on Friday.

"Now I'm worried," said Paula Clark, who was preparing to board a Frontier flight to Denver. "I'd hope the plane she flew on they've got quarantined."

Frontier took the plane in question out of service and it was being decontaminated at Cleveland's airport, the local ABC TV reported.

Though Clark and others expressed concern for their families, they said it would be an overreaction to stop flying.

"You have to keep living," Clark said.

Across town at the crowded Texas State Fair, Ebola was a hot topic of conversation between rollercoaster rides, foot-long corn dogs, and visits to the petting zoo.

"It's all scary. I just saw three little kids go by wearing face masks and gloves. That's the first time I've seen that," said a worker at a promotional booth for a large company who declined to give her full name because she is not authorized to speak to the media.

Edgar Loera, a nursing student who was visiting the fair with two friends, said there was no need to panic.

"You don't need a mask. It doesn't pass through the air, so it is not that easy to get," he said. "The nurses got it because they didn't have the right equipment.