SPRINGFIELD, Mo. -- A nurse who refused to wear a surgical mask after receiving an exemption from a mandatory flu vaccination was fired for violating her hospital's policy.

CarlaBrock, a board-certified holistic nurse who has worked 11 years at CoxSouth Hospital here, said she is speaking out because she believes herhospital's new requirement to wear a mask if a staffer opts out of theflu vaccine amounts to a scarlet letter. CoxHealth, which owns fourhospitals in southwest Missouri and northwest Arkansas, says it simplyis putting the patient first.

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"I love my job, and I loved thepeople I worked with," the pre-admissions nurse said. But "I havespiritual and religious reasons to not have those toxins in my body."

Mandatedflu shots already are part of a national debate that pits employeerights against what some say is patient safety. Most recently, inDecember, an Indiana hospital fired eight employees who refused to get flu shots, according to ABC News.

Brock'ssituation adds another layer to the debate. This is the first year thatCoxHealth employees are required either to get the vaccination orproduce paperwork showing an exemption, according to Stacy Fender, mediarelations coordinator for CoxHealth. In the past, flu shots werestrongly recommended.

In early September, Brock sought and wasgranted a religious exemption although she admits she's more "spiritual"than "religious."

"We jumped through the hoops," she said. "We did all the right things."

ButCoxHealth's new policy also requires employees who receive an exemptionto wear a surgical mask while working, which Brock did starting Dec.31.

Plenty of people are fighting against the flu vaccine requirement. Brock is fighting against the mask requirement.

"It's obviously punitive," she said. "It's obviously coercive."

Brock believes the masks are meant to intimidate and humiliate thosewho seek an exemption so they will conform and get the shot rather thanstand out.

"The 'scarlet letter' word keeps coming up," she said.

Brockalso believes that there is no evidence that the mask policy iseffective and noted that hospital visitors don't have to wear them.

"If that's the case, Cox should have every single person who walks in the door wear a mask," she said.

Patientsawaiting surgery were taken aback when Brock would enter the roomwearing a mask, fearing something was wrong, she said. That forced herto explain the situation and in the process divulge more about herselfthan she wanted to.

"I felt like I was violating my own privacy," she said.

Brockalso said the masks made it difficult for her to breathe and gave herheadaches. She started pulling the mask away from her face buteventually just took it off when she was in the room with one patient.

"I told him, 'I'm sorry. I'm not contagious. I just can't do my job with this on,' " she said.

Throughout the past week, Brock sent messages detailing her objections to her managers.

On Friday, an employee relations manager told her she needed toprovide medical documents to substantiate her condition if she thoughtshe had a medical condition that prevented her from wearing the mask.

This past weekend, Brock said she met with others, including the minister who provided documentation of her religious exemption.

Shedoesn't have a medical condition, she said. In fact, her preference forholistic health means she doesn't even have a primary-care physician.On Monday, she presented a letter saying that she would not wear themask and was terminated.

"It is a Cox standard and becoming anational standard from Colorado, where it is a state mandate fornon-vaccinated healthcare workers," her corrective action memo read.

Brock is most frustrated because she thought she had no options.

"I've tried to communicate a different viewpoint, but there's been no willingness to reconsider," she said.

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Inmore than a decade of working for CoxHealth, Brock had faceddisciplinary action only one other time, she said, when she acquired hermother's lab results with her mom's permission but without followingprotocol. She felt that situation was handled appropriately.

Fender,the CoxHealth spokeswoman, said the hospital does not comment onindividual personnel issues but did offer an explanation of thehospital's mask policy.

"The logic behind it is that you canspread the flu before you have symptoms of it," Fender said. "The wayyou spread the flu is through your upper respiratory system, so the maskcontains that."

Fender said that 99% of CoxHealth's employees are vaccinated.

"Ourpolicy is similar to hundreds if not thousands of health systems acrossthe country," she said. "Our first priority has to be the patients."

Anotherarea hospital, Mercy Hospital Springfield, started requiring itsemployees get a vaccination or wear a mask in 2010. A representativeMonday said she was not aware of any employee push-backs against Mercy'smask policy.

Brock is not alone in her feelings about the masks. Staff members at hospitals in Worchester, Mass., and Boston have complained about the masks as more health care providers have made them a requirement, according to media reports.

Butat least one decision following dissent has given Brock hope. InDecember 2011, the University of Missouri Health Care network backed offits mask requirement.

"We reviewed national guidelines anddetermined it wasn't clear if this procedure would actually improvepatient or staff safety," spokeswoman Mary Jenkins told The Columbia (Mo.) Daily Tribune in 2011.

Brocksaid her husband is supportive of her decision, although thetermination will create some hardships for them. As a side business, sheteaches holistic health classes, including one called "The Danger ofVaccines."

Brock is not yet sure if she will take legal action.

"If I have legal rights, I want to exercise them," she said. "I want to at least consider it."