CNN  — 

In the past week, America took two big steps closer to a semblance of the normalcy we’ve longed for.

On Monday, the Food and Drug Administration expanded its emergency use authorization for Pfizer’s Covid-19 vaccine to include people 12 to 15 years old. And on Thursday, the Centers for Disease Control and Prevention announced fully vaccinated Americans do not need to wear masks or socially distance indoors or outdoors, with some exceptions.

It didn’t take long for the CDC guidance to trigger changes across the country.

State leaders across the US announced they were dropping mask requirements for fully vaccinated residents. Retailers and other businesses – including Trader Joe’s, Walmart, Starbucks and Publix – also announced changes to their masking policies.

But the country may be moving too quickly and not focusing enough on the key part of CDC’s guidelines, one expert told CNN on Saturday.

“We should be emphasizing ‘fully vaccinated’ in the context of mask guideline changes and not just taking your mask off, because it’s causing businesses – schools even – to start to change their policy a bit prematurely and without the full picture of the guidelines,” infectious disease expert Jessica Malaty Rivera said.

And the quick changes have left some parts of the country now relying on an honor system, other experts say.

“The CDC went from 0 to 100 overnight,” emergency physician and CNN Medical Analyst Dr. Leana Wen told CNN Saturday. While Wen agrees with the approach of letting fully vaccinated Americans return to normal, she said there should be some kind of verification process in place for that to work.

“The CDC is relying on the honor code, and we’re seeing that the honor code is already not working,” Wen said. “There are already many states and businesses that are essentially just taking their guidance and saying ‘that means that mask mandates and distancing all needs to end.’”

And what that means: “We’ve just made life so much less safe for those who are not vaccinated and for those who are immuno-compromised and may not get the full benefit of the vaccines,” Wen said.

The CDC defines people who are fully vaccinated as those who are two weeks past their second dose of the Moderna or Pfizer Covid-19 vaccines or two weeks past the Johnson & Johnson single shot.

A customer exits a corner market while wearing a mask in the retail shopping district of the SoHo neighborhood of the Manhattan borough of New York on May 14, 2021

‘We’re asked to trust other adults’

Dr. Anthony Fauci told CNN last month he estimates about 70-85% of people need to be immune to the virus for the country to reach a “total blanket of protection.” So far, a little more than 47% of the US population has received at least one Covid-19 vaccine dose, according to CDC data. Roughly 36.7% of the country is fully vaccinated.

With such a big part of the country still unvaccinated, one expert said he wished the guidance was the first of what could have been a two-part system to help Americans shed their masks.

“If I’m indoors and I’m around people who are vaccinated, I feel comfortable not wearing a mask, but if I’m indoors and there are 50 people in that, let’s say in the grocery store, and I see 25 people who aren’t masked, I have to assume that they’re vaccinated and I think that’s a big assumption,” said Dr. Paul Offit, director of the Vaccine Education Center at the Children’s Hospital of Philadelphia.

Instead, Offit also said he had hoped officials would have provided a way to verify that Americans who want to go maskless indoors have been vaccinated.

“That didn’t happen,” he said. “Now, we’re asked to trust other adults in a situation where there’s every reason not to trust a lot of people right now because there’s so much denialism out there. There’s so many people who don’t wear masks, who don’t get vaccinated.”

But some of the people who have yet to get a shot haven’t gotten one because of problems with access – and businesses should take that into consideration before lifting mask requirements, emergency physician Dr. Megan Ranney said.

“I would urge businesses to keep those mask mandates in place as long as possible in their businesses to protect their workers,” she said. “It’s particularly an equity issue. We know that Black and Brown folks across the United States who are most often our frontline employees with public facing jobs, are also those who have had the hardest time accessing the vaccines.”

Where mask policies aren’t changing

Despite the sweeping changes, the requirement to wear masks during travel – on buses, trains, planes and public transportation – still stands, CDC Director Dr. Rochelle Walensky said last week. And the transportation industry says it will continue to strictly enforce mask use.

“There’s a mask order in place and it will be enforced, period,” Association of Flight Attendants President Sara Nelson told CNN.

The Transportation Security Administration said last week the federal transportation mask mandate will remain in place through September 13 on commercial flights, trains, buses, boats and in terminals.

The CDC also said Saturday that schools should continue masking and using other coronavirus prevention strategies for at least the rest of this school year.

Those strategies will be needed because students – the ones who are authorized to receive a shot – won’t be fully vaccinated by the end of the academic year, the CDC said.

“Because people are not fully vaccinated until 2 weeks after their second dose of the Pfizer vaccine, students in this age group will not be fully vaccinated before the end of current school year,” the agency said.

Children under the age of 12 are not yet eligible to receive a Covid-19 vaccine in the US.

Walensky, the CDC chief, told ABC on Friday children and educators should expect a return to in-person, full-time school by the fall.

“We have the capacity now, between vaccines and testing, screening, we believe schools can and should be a very safe place for people to go back to in the fall.”

She added that the agency still needs more data in order to make recommendations on Covid-19 vaccination requirements for returning to school.

CNN’s Lauren Mascarenhas, Virginia Langmaid and Pete Muntean contributed to this report.