Coronavirus FAQ: I'm vaccinated and confused. Do I need to mask up or not?

Don't toss your masks out just yet. As the more transmissible delta variant takes hold, and some countries are reinstating precautions, even vaccinated people may want to mask up in certain situations.

"People cannot feel safe just because they had the two doses. They still need to protect themselves," Dr. Mariangela Simao, World Health Organization assistant director-general for access to medicines and health products, told reporters on Friday. "Vaccine alone won't stop community transmission. People need to continue to use masks consistently, be in ventilated spaces, hand hygiene ... the physical distance, avoid crowding. This still continues to be extremely important, even if you're vaccinated when you have a community transmission ongoing."

"WHO is recommending wearing masks even if vaccinated because breakthrough infections will happen with any of the vaccines and if spread into a highly unvaccinated community (because the majority of the world has not been vaccinated) there could be widespread disease that occurs and new outbreaks developing," says Dr. Jill Weatherhead, assistant professor of adult and pediatric infectious diseases at Baylor College of Medicine in Houston, in an email. "This is true for any variant, but because the delta variant is highly transmissible it will more readily spread throughout communities."

The Los Angeles County Department of Public Health is also recommending masking up indoors due to the delta variant.

But not all public health agencies are as cautious. In the U.S., guidelines from the Centers for Disease Control and Prevention (CDC) no longer require you to wear a mask in most settings if you're fully vaccinated (that means two weeks after the final dose), and most states have lifted restrictions as well. (Transportation hubs and medical facilities still require everyone to mask up, as do some businesses.)

So with the WHO urging vaccinated people to mask up and the CDC saying it's up to you, confusion is understandable. Essentially it means that most vaccinated Americans have a choice to make.

They "need to make the decision that's best for them and their family at this point," says Dr. Leana Wen, an emergency physician and public health professor at George Washington University. "It's this in-between time in the pandemic, when there's no one-size-fits-all answer. Everybody has different values and risk tolerances. If you're vaccinated, you can choose in terms of whether to wear a mask or not."

That choice may depend on extenuating circumstances, including whether you live with unvaccinated kids or immunocompromised people, the rate of community transmission in your area and the rate of vaccination in your area.

For many people, it will mean masking up in certain situations.

"If you are vaccinated with one of the vaccines authorized in the U.S., you are well-protected from COVID-19," Wen says. "This protection is not 100 percent, and especially with the rise of the more contagious delta variant, some who are inoculated may choose to wear masks in indoor, crowded settings when they are around others who are not known to be vaccinated. ... People need to decide the level of risk that they are comfortable with."

For Wen, that means she and her husband continue to wear masks in places where they're not sure everyone is vaccinated, such as the grocery store and church, since their children aren't old enough to be vaccinated. Play dates happen outside, she says. They live in Baltimore, where the test positivity rate currently qualifies as low.

Weatherhead, who also has children too young to be vaccinated, employs similar caution.

"Even though we've had a decrease in cases — and especially hospitalizations — there's still ongoing transmission in the environment so there is still a risk," she says. "We're certainly not through the pandemic at this point. We're improving, but there's still ongoing community transmission in much of the country. Particularly with the increase of the delta variant, there are going to be breakthroughs even if you're vaccinated. Unvaccinated people are certainly at the highest risk, but there still can be breakthrough infections as delta gains increase in prevalence."

If you do choose to wear a mask, there's probably no need to worry that others will take it as a sign you're unvaccinated: "I actually think that the people wearing masks now tend to be the vaccinated and people understand that," Wen says. And since some people, such as kids under 12, can't be vaccinated at this time, mask-wearing could be a sign people are trying to protect the unvaccinated, she says.

Even when the current pandemic threat fades, you may want to stash your masks somewhere handy. Weatherhead and Wen say they hope that it will become more socially acceptable to wear masks in the U.S. to ward off the flu and other viruses.

"It might be something people will choose to want to wear, though not required," Weatherhead says. "Culturally we have never worn masks before here. In other countries it's more common, but it's never been something we've done here. There's probably been a little shift where people feel more comfortable wearing masks in public to protect themselves" — or others, she notes, if you have to go out in public while under the weather. (Of course, she adds, "If we've learned one thing from the pandemic, it's that when you're sick, you shouldn't be in public!")

If you're looking forward to giving up a pandemic precautionary routine, make it the hand sanitizer and disinfectant wipes: There shouldn't be a need to wipe everything down going forward, Weatherhead says. Washing your hands with soap and water, however? "That's always appropriate."

Copyright 2021 NPR. To see more, visit https://www.npr.org.

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