Nurses and other health care providers are being advised they may have to use homemade masks devised from scarves and bandanas should the supply of FDA-cleared masks run out.

The U.S. Centers for Disease Control and Prevention calls homemade masks a "last resort" to be used only during a crisis, because their capability to protect is unknown.

"Caution should be exercised when considering this option," the CDC's website states.

The directive comes as nurses and other health care workers in Wisconsin are grappling with a shortage of masks, gowns and other gear to protect them from COVID-19.

The Milwaukee Journal Sentinel has heard from nearly a dozen health care workers from hospitals in Milwaukee and Madison who report they have no protective masks or that they have been required to wear a single mask all day.

“This is cause for concern,” said Gina Dennik-Champion, executive director of the Wisconsin Nursing Association, an advocacy group for the state’s roughly 90,000 nurses.

Masks degrade the longer you wear them and can become contaminated when you reuse them.

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But Dennik-Champion said that nurses have few choices. "It’s that or nothing at this stage of the game,” she said.

One nurse, who did not want to be named out of fear of retribution from Children’s Hospital, where she works, said wearing the same mask for extended periods is a huge risk.

“It flies in the face of what we’ve been taught about infection control,” she said. “I don’t think anybody would say it’s appropriate to reuse these items.”

Children's Hospital spokesman Andrew Brodzeller said Wednesday it makes sense that nurses might be uneasy about not switching masks but that the hospital is following federal Centers for Disease Control and Prevention guidelines on supply conservation.

"These guidelines are evolving every day. They are different than what has been typically followed under normal conditions,” he said. “It’s natural that they would have questions."

The lack of personal protective equipment is slowing the ability to test for COVID-19, Wisconsin lawmakers said in a letter Thursday to the U.S Food and Drug Administration.

Saying “Wisconsin needs your help NOW,” the state’s congressional delegation asked the FDA to direct more coronavirus testing supplies to Wisconsin, citing the “dire consequences” of a testing bottleneck at hospitals.

The bipartisan letter was signed by both Wisconsin senators and the state’s seven currently serving House members.

In an interview, Democratic Sen. Tammy Baldwin said that because hospitals are running out of supplies for things like swabs and protective gear and reagents for analysis of samples, the promise of testing “becomes an empty promise.”

“The lack of clinic and hospital-based personal protective equipment for our health care providers is alarming,” she said.

“We have several hospitals that have already set up their own labs, and more are scheduled to come on line in the coming days. However, they are unable to obtain the equipment and supplies necessary to complete testing, leaving a significant amount of untapped capacity.

“This testing bottleneck is creating dire consequences for our hospitals and their staff," she said. "These delays only increase the risk of COVID-19 spread."

Officials at Advocate Aurora said Wednesday that their facilities are taking measures to conserve protective masks and gowns and said they, too, are following the CDC guidelines.

The CDC suggests hospitals try to limit the number of staff who need the highly protective N95 masks and to use other, less protective masks when possible.

Extended use of N95 masks should be reserved for limited circumstances, according to CDC guidelines. “Extended use may be implemented when multiple patients are infected with the same respiratory pathogen and patients are placed together in dedicated waiting rooms or hospital wards," the guidelines state.

Froedtert & the Medical College of Wisconsin staff and clinicians are also following conservation strategies, said hospital spokesman Stephen Schooff.

The hospital has supplemented disposable gowns with industry-approved reusable gowns and is limiting the number of providers who enter the rooms of patients requiring isolation, he said.

Charles de la Pena, a lab technician at Froedtert’s Wisconsin Diagnostics Laboratories, said the microbiologists testing for COVID-19 have proper gear but that others in the lab don’t.

“Right now we’re not very well-prepared to deal with the situation,” de la Pena said. “We run the risk of one of the workers becoming infected and then sharing it and putting everybody out of work.”

He said he requested a meeting with management nearly two weeks ago to discuss preparation, but it was put off until later this week.

“It’s a little late in the process now,” he said.

On Tuesday, state Health Secretary Andrea Palm said the agency received word from the federal government that Wisconsin will receive a small allotment of a variety of pieces of equipment from the strategic national stockpile.

“The team is currently working through how we prioritize, how we work through the deployment of what we are receiving from the stockpile,” Palm said. “We know there are shortages of a variety of supplies," including personal protective equipment, she said.

Palm said she expects the problem to continue and that the agency is doing everything to get as many supplies from the strategic national stockpile as possible.

Ryan Nilsestuen, Wisconsin Gov. Tony Evers’ chief legal counsel, said officials are surveying what each health system needs for supplies.

“I think there are real shortages that we’re hearing about, and it’s not only one type of supply,” he said. “We’ve heard about shortages of gloves and gowns and masks and face shields.”

Nilsestuen said the governor’s office is responding “as best we can.”

Wisconsin is eligible to receive 54,709 N95 respirator masks, 130,326 surgical masks and more than 20,000 gowns from the national stockpile, according to a March 17 letter from U.S. Senator Tammy Baldwin to the U.S. Department of Health and Human Services.

Jeff Pothof, the chief quality officer at UW Health, described what's going on at the hospital as "kind of like a controlled pandemonium."

While the hospital has plans in place for dealing with situations of this kind, there has never actually been a situation of this kind.

"The speed by which we have to make and implement changes is blistering. Every day we're making changes, and every day the rules seem to change," he said, citing the varying travel and testing rules that have been announced.

"My biggest concern is: Are we going to have enough masks to get through this?" Pothof said.

Pothof also said the hospital is low on full-body protective suits. "We're a little bit short on those, but we're doing OK," he said, adding that he is also tracking the hospital's supply of gloves.

Possible COVID-19 cases are being taken to the hospital's Special Pathogens Unit, which has about 30 beds. As it fills, there is a trigger point at which hospital staff begin to ready the next unit to take any overflow patients.

In a press release Wednesday, the Wisconsin Federation of Nurses and Health Professionals called for “drastic action” from hospital executives and government officials to protect healthcare workers.

“Healthcare workers are on the front lines of this battle, and the health of our community depends on their ability to do their jobs,” leaders of the organization wrote. “Our healthcare ecosystem is unable to meet the influx of needed care, but there are common-sense changes that need to be enacted immediately so that we have a chance to rest and recover as individuals and as a community.”

Added Jeff Weber, a 25-year veteran registered nurse: “It’s the Wisconsin way to take care of each other in times of need, and we all need to do our part to stop the hurt.”

Craig Gilbert and Patrick Marley of the Journal Sentinel contributed to this story.