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People who are fully vaccinated against COVID-19 can now feel free to ditch their masks in most places, the Centers for Disease Control and Prevention announced last week to the surprise of many.

On Thursday, the CDC released updated guidelines for the nearly 124 million Americans now fully immunized against COVID-19. They no longer need to wear masks or maintain social distance during regular activities, the CDC says, except where required by federal, state, local or tribal laws, and regulations.

The new recommendations rest on many months of scientific evidence that COVID-19 vaccines are not only extremely effective at preventing severe illness and death, but also reduce a person’s risk of catching the virus and spreading it to others. It’s also a reflection of the country’s growing ranks of immunized individuals (nearly half of U.S. adults are fully immunized).  

“The vaccine is remarkably effective,” says Buddy Creech, a pediatric infectious disease specialist at Vanderbilt University and director of its vaccine research program. “Once you’re vaccinated, CDC guidance has evolved to say you can go back to life as usual.”

Over the weekend, CDC Director Rochelle Walensky noted that despite the announcement, unvaccinated children, people with compromised immune systems, and those living in communities with high COVID-19 case numbers should keep masking and social distancing. 

“The recommendations for those settings have not changed,” Walensky told CNN. 

Throughout the pandemic, children have been at lower risk than adults of getting seriously ill or dying of COVID-19, but the new CDC guidelines have opened up questions from parents and guardians of children who are not vaccinated or not yet eligible for vaccines. 

“It makes it more complicated, quite frankly. It’s easier to say ‘Just wear a mask,’” Creech says. Instead, this is the beginning of a future in which we have to live alongside a “smoldering baseline amount of coronavirus circulating.” When vaccinated people should leave their masks at home—and when to mask up—is “going to look different for every person,” he says.

“Nothing in a pandemic is simple,” says Tony Moody, a professor of pediatrics and infectious diseases at Duke University Medical Center, and director of the school’s vaccine center. Here are some key considerations for parents and guardians as they navigate this period of the pandemic.

Should vaccinated adults with unvaccinated kids keep wearing masks?

It depends, experts say.

“A vaccinated adult probably is okay going unmasked,” Moody says. “That being said, there is some utility to parents modeling behavior for their kids.”

Since the CDC recommends unvaccinated children continue masking, parents might have an easier time convincing their kids to keep masks on if it’s the standard for the whole family.

Under CDC guidance, unvaccinated children should still wear masks indoors when around people outside of their bubble, since they are still at risk of becoming infected with the virus and spreading it to others—even if they don’t develop symptoms. But vaccinated parents deciding whether they want to unmask at indoor gatherings should consider factors including how many other people will be there, vaccination status of other attendees, and the local rates of COVID-19 infections. 

After all, a packed music venue and a small dinner party pose very different levels of risk.

“There’s a whole lot of space in between there,” Moody says. “Just existing as a human is risky. I think situations where you have less control, be appropriately cautious.”

What about vaccinated grandparents with unvaccinated grandkids?

Throughout the pandemic, older adults have been at highest risk of severe disease or death from COVID-19. Now that almost three out of four Americans ages 65 or older are fully vaccinated, the risk of a grandchild getting their grandparents seriously sick has been significantly reduced.

“In an individual, extended family unit, what’s most critical is that those who are most vulnerable are vaccinated,” Creech says. After that point, it’s a matter of deciding how much risk is worth taking. 

For immunized grandparents, Moody says, exposure to an unmasked, unvaccinated grandchild poses about as much of a health risk as exposure to a sniffling grandchild would during the typical cold season. 

[Read more: Fully vaccinated people no longer need to wear masks—but there’s a catch]

What precautions should vaccinated adults take while traveling with kids?

In its new guidance, the CDC relaxed some requirements for travel.

Vaccinated adults no longer need to be tested before or after domestic travel, for example. (International travelers are still required to do so before and after their trips.)

But regardless of age or vaccine status, mask mandates will remain in place on planes, buses, trains, and other forms of public transportation—as well as at transit hubs such as airports and bus stations. 

Experts have also advised that parents keep in mind local case rates when deciding whether and where to travel with children. Traveling to a community where infection rates are high and vaccine rates are low, for example, poses a higher health risk.   

What do the guidelines mean for schools?

On Saturday, the CDC clarified it still recommends the universal use of masks and physical distancing in K-12 schools through the end of the 2020-2021 school year despite its updated guidance for vaccinated Americans. 

It also still recommends the continued use of diagnostic testing for any students, teachers, or staff members with COVID-19 symptoms at school.

“Our school guidance to complete the school year will not change,” Walensky said on “Fox News Sunday.” Over the summer, she said, the agency will consider making guidance changes for the 2021-2022 school year.

One potential setback for schools: If any SARS-CoV-2 variants become clearly more dangerous for children, those protections could stay in place for longer, Creech says.

[Read more: Pfizer and Moderna are studying their COVID vaccines in kids as young as 6 months]

When will younger kids be eligible and what needs to happen first? 

Last week, the U.S. Food and Drug Administration cleared Pfizer’s COVID-19 vaccine for use in kids as young as 12. 

Juvenile and adolescent trials are currently underway for other vaccines, too, Creech says, to make sure they are also safe and effective for the nation’s youngest residents, including infants and toddlers.

“Children are not merely little adults,” he says. “The studies have to be done and those data are going to take some time to come out.”

It could be winter 2021 or early 2022 before we have widespread vaccine eligibility, he says.

“It’s a little hard to say. The goal, ultimately, is to get this vaccination down to as young as 2 months,” Moody says. “They’re being appropriately cautious. They’re not rushing anything.”