Cheri Willner, the co-owner of Knead Bagels near Washington Square Park, knows how easily the coronavirus can spread.

In between her first and second vaccine doses in March, Willner said she and her family were infected with COVID-19. She had to close her business for two weeks while ensuring no one else got sick.

Now, Willner, like many other business owners in the Philadelphia region, will not be lifting their mask mandate, despite the CDC’s newest guidance that fully vaccinated people are safe to shed their face covering outdoors and in most indoor settings.

For everybody’s safety we will keep the mask wearing until further notice, which is the same reason we are not doing any indoor dining,” said Willner. “We’re taking the time to do it right, doing it safe.”

While other businesses said they are also keeping their mask mandates, giving customers and employees more time to become fully vaccinated, at least two major retailers said vaccinated customers could shop mask-free. The CDC’s updated guidance Thursday was both a recognition of the effectiveness of vaccines and a surprise to many not yet prepared to loosen guidelines.

Although the percentage of adults who are vaccinated continues to rise, the majority of the population is still not inoculated. Workers said they do not want to be put in what they described as an impossible enforcement situation: Determining if someone is truly vaccinated or not.

Willner, for example, worries that people could lie about their vaccination status in order to forgo masks. She hopes the CDC’s announcement does not embolden customers who don’t want to follow the rules.

The guidance comes after mounting evidence that it is extremely rare for a fully vaccinated person to become infected with the coronavirus or spread it to others.

The Pennsylvania Department of Health adopted the CDC’s new guidance, but also announced Friday that fully vaccinated people will have to wear a mask if a business or organization requires it. Universal masking requirements remain in effect for people who are unvaccinated and will stay in place until 70% of Pennsylvanians over age 18 are fully vaccinated. Today, fewer than 50% of those adults are fully vaccinated.

In Philadelphia, where just 34.5% of residents age 16 and older are fully vaccinated, the Department of Health is reviewing the CDC’s new guidance and is expected to have a decision on updated rules “within days,” according to a city spokesperson. New Jersey will continue to mandate masks indoors even for fully vaccinated people, Gov. Phil Murphy said during an vaccine event with Whoopi Goldberg Friday.

This leaves many businesses to decide for themselves how to proceed. Home Depot, Giant, Rite Aid, and Target said in statements to The Inquirer that they aren’t changing their mask policies at this time.

“Target will continue to require all of our coronavirus safety measures in all stores, including masks and social distancing, while we review updated guidance from the CDC and reevaluate the guidance we offer our team and guests,” a Target spokesperson said in a statement.

Meanwhile, Trader Joe’s became one of the first national businesses on Friday to announce it would relax its mask mandate, allowing fully vaccinated people to go without any face coverings. The company said it will not request or require proof of vaccination.

Walmart said in a memo to staff that fully vaccinated customers can shop mask-free as of Friday, and fully vaccinated employees can forgo masks starting May 18, as long as that doesn’t conflict with local regulations. The memo did not say if the company would require proof of vaccination from customers. Staff must tell the company they are vaccinated to work mask-less.

Neil Goldfarb, the president and CEO for the Greater Philadelphia Business Coalition on Health, said he would advise his members, which include Comcast, Aramark, and Wawa, to “take a wait and see attitude.”

“It’s going to be very difficult to ask the employers to police this particularly in the short term,” Goldfarb said. “Don’t do a major change in policy. Let the dust settle. And keep encouraging people to get vaccinated.”

Mala Sharma, 26, a front-desk receptionist at Sanatoga Animal Hospital in Montgomery County, said she wished the CDC guidance included more specific recommendations for small businesses. For now, she said, her workplace is continuing with mask mandates.

“I see where they’re coming from scientifically,” Sharma said of the CDC. “I just don’t see how it works practically for businesses. There’s no way to prove with finality that someone has been vaccinated fully.”

Wendell Young IV, the president of food and commercial workers union UFCW Local 1776, said he relayed to grocers that he believes mask mandates should stay in place a bit longer and most businesses agreed.

Young was glad to hear Acme was continuing with its mask mandate, but hopes customers don’t give workers a hard time. He said a union representative was inside a Philadelphia-area Acme Thursday when the CDC news broke. The representative told Young how he saw customers read the announcement on their phones and then remove their masks. An employee soon made an announcement that the grocer was still enforcing mask wearing.

Acme did not respond to a request for comment on its mask policy, but its website still noted Friday that all customers are required to wear face coverings.

The Retail Industry Leaders Association said the revised guidance conflicts with many local and state guidelines that still have mask mandates, putting retailers and workers “in incredibly difficult situations.”

Rufina Rodriguez, a 43-year-old Philadelphia domestic worker, is fully vaccinated but still plans to wear a mask at work.

She still worries about the rare chance of getting sick and bringing the virus home to her husband who has diabetes and her 11-year-old son who is not yet eligible for the vaccine. She wishes the CDC continued to recommend masks in most settings.

“I have had both doses of the vaccine, but I still don’t feel safe going without my mask,” she said in Spanish through a translator.

A La Colombe employee, who did not want to be named due to the politicized argument around masks, said she faced more customers than usual on Friday who were questioning the company’s mask policy. The company didn’t respond to a request for comment.

“People are a lot more relaxed and it’s putting a lot more pressure on workers to enforce the company policy,” she said. “It’s always a question as an employee: Is it going to be worth it to confront this person? Will they retaliate?”