CDC on Friday announced new guidance saying fully vaccinated Americans can forgo masks in most situations both indoors and outdoors. But as some states and private businesses still have mask mandates, the new guidance has prompted confusion nationwide and criticism from some health experts.

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CDC's new guidance prompts confusion, criticism

The new guidance states that fully vaccinated Americans can be maskless indoors and outdoors in most situations. However, CDC made some exceptions to that rule, saying vaccinated Americans should continue wearing masks in health care facilities, such as hospitals; on public transit and during air travel; when around the immunocompromised; and in congregate settings, such as homeless shelters or jails. CDC added vaccinated Americans should also continue to abide by local and federal mask mandates.

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Given that some states still have mask mandates in place and private businesses are allowed to set their own masking requirements, the new guidance prompted confusion from some business owners.

"At first, as a citizen, I was like, 'Wow, these are so great. I haven't been out to eat in a year," Angela Garbacz, a pastry shop owner in Nebraska, said. "But as a private business owner, it has been like panic and, 'What do we do?' Are people just going to think they can come in without masks? Do I get rid of my mask requirement? It's just so much uncertainty with the one thing that's helped us feel safe in a really scary time."

Some health experts, including Leana Wen, visiting professor at the George Washington University Milken Institute School of Public Health, were critical of the new guidance. Wen said it "could end up increasing confusion, removing incentives for those yet to be inoculated, and delaying the eventual goal of herd immunity that would get society truly back to normal."

Wen added that she believes "CDC meant to say something really good, which is these vaccines are really protective. The thing is though, there were unintended consequences of their actions."

As a result of the new guidance, "we've seen governors and mayors and business owners drop mask mandates, and as a result of that we've now made life much less safe for people who are unvaccinated, for immunocompromised individuals, and for young children who cannot yet be vaccinated," Wen said.

Jonathan Reiner, a professor of medicine and surgery at George Washington University, said he believes CDC "has gotten the science right, but [it's] gotten the messaging wrong."

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Fully vaccinated people are "basically immune" to the new coronavirus, Reiner said, but communities still face a challenge in protecting children, people who haven't been vaccinated, and the immunocompromised.

"The way you would protect them, ideally, would be to know who's vaccinated and who's not vaccinated, and the unvaccinated folks would still be required to wear a mask. And this is where politics come in," Reiner said. "If we had had a very simple electronic system from the beginning, basically you have a pass on your phone that turns green after you've been vaccinated, businesses and venues all over the country would be able to say, 'Good news, if you have a green pass you don't need to wear a mask.'" But no such commonly accepted system exists.

Some union groups also took issue with the guidance. The California Nurses Association (CNA) , an affiliate of the National Nurses United (NNU), criticized the guidance, with CNA president Zenei Triunfo-Cortez saying the guidance is "a big blow to the safety and welfare of the nurses, front-line workers, as well as the patients."

NNU added that there remains uncertainty around the protection provided by Covid-19 vaccines, including how long it lasts. "Now is not the time to relax protective measures, and we are outraged that the CDC has done just that while we are still in the midst of the deadliest pandemic in a century," Bonnie Castillo, NNU executive director, said.

"Millions of Americans are doing the right thing and getting vaccinated, but essential workers are still forced to play 'mask police' for shoppers who are unvaccinated and refuse to follow local Covid safety measures," Marc Perrone, president of United Food and Commercial Workers International, said. "Are they now supposed to become the vaccination police?"

Federal health officials defend guidance

CDC Director Rochelle Walensky on Sunday said she is "delivering the science as the science is delivered to the medical journals and…it evolved over this last week." She continued, "I delivered it as soon as I can when we have that information available."

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Walensky added that "not everybody has to rip off their mask because our guidance changed."

"If you are vaccinated, we are saying you are safe. You can take off your mask and you are not at risk of severe disease or hospitalization from Covid-19," she said. "If you are not vaccinated, you are not safe. Please go get vaccinated or continue to wear your mask."

Walensky added she's "cautiously optimistic" about the epidemic but said it's still too early to "declare victory."

Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said CDC's new guidance "was just based on the evolution of the science."

Specifically, three factors drove the change, Fauci said: data showing the "real-world effectiveness" of Covid-19 vaccines, new studies showing the vaccines effectively protect against coronavirus variants, and data showing that vaccinated people are unlikely to transmit the virus to someone else.

"The accumulation of all of those scientific facts, information, and evidence brought the CDC to make the decision to say now when you're vaccinated, you don't need to wear a mask, not only outdoors, but you don't need to wear it indoors," Fauci said.

However, Fauci added that he believes "within a period of just a couple of weeks, you're going to start to see significant clarification of some of the actually understandable and reasonable questions that people are asking" (Reed, "Vitals," Axios, 5/17; Flores, San Francisco Chronicle, 5/16; Maxouris, CNN, 5/17; Gaffney et. al., Washington Post, 5/16; Kruesi, Associated Press, 5/16; Weaver, Politico, 5/16; Rubin/Abbott, Wall Street Journal, 5/16; Quinn, CBS News, 5/17; Richtel et. al., New York Times, 5/16).