How to navigate the CDC's new mask guidance: Experts' surprising advice

Many Americans vaccinated against COVID-19 were confused earlier this week when the Centers for Disease Control and Prevention announced updated guidance that encourages them to wear a mask when they're indoors, in public spaces in areas where there are "substantial or high" levels of the virus. The move is a 180 from guidance released in mid-May that said people who are fully vaccinated against COVID-19 no longer need to wear masks.

There has been a lot of talk about what, exactly, this means for people — and plenty of questions. "Can someone tell us what substantial or high means????" one person wrote on Twitter. "Why schools and no other indoor [institutions]? I understand elementary schools bc younger ones can't be vaccinated, [but] why K-12?" another said.

People wear masks in Grand Central Terminal in New York City on July 27. (Spencer Platt/Getty Images)
People wear masks in Grand Central Terminal in New York City on July 27. (Spencer Platt/Getty Images)

There have also been plenty of questions about what this means for things like attending weddings and wearing a mask in your own home when you have company. The CDC hasn't covered all of the nuances, but infectious disease experts have some insight. Here's a breakdown of some of the biggest questions many people have around masking up again, and what it means for you.

How do you know if you should be masking indoors?

The CDC has an easy-to-use interactive map online that allows you to search for COVID-19 data by state and county. Simply enter your information and you'll get results that tell you if COVID-19 transmission in your area is low, moderate, substantial or high. It also provides a breakdown of vaccination data in your area, such as how many adults are fully vaccinated.

Do you need to start masking indoors in your home?

It depends on a few things, including your personal risk tolerance. Technically, the updated CDC guidance "is only applicable to places with high or substantial transmission and only for public places, so [it] does not suggest people wear masks in their own homes," infectious disease expert Dr. Amesh A. Adalja, a senior scholar at the Johns Hopkins Center for Health Security, tells Yahoo Life.

But it's important to consider the vaccination status of your guests, Dr. William Schaffner, an infectious disease specialist and professor at the Vanderbilt University School of Medicine, tells Yahoo Life. "If your guests are vaccinated, you do not need to wear a mask," he says. "It's having unvaccinated people over to your house where there's a real concern."

Are doctors changing their behavior with the latest guidance?

Not really. "I have some gray hair, so I've been wearing my mask all along," Schaffner says, pointing out that he wears his mask when he makes early Saturday-morning grocery runs and in other public spaces.

But Adalja says that he is "not changing my behavior," which includes indoor dining. Neither has Dr. Thomas Russo, a professor and chief of infectious disease at the University at Buffalo in New York. "I have not been using masks in indoor or outdoor settings," he says. But, he points out, he lives in an area that has "moderate" spread. "We still have a bit of leeway," he adds.

"Personally, I don't think the science at this point supports masking for vaccinated people," Dr. Lewis Nelson, chair of the Department of Emergency Medicine at Rutgers New Jersey Medical School, tells Yahoo Life. "But the problem is, there's no way to know who is vaccinated and who is not. From a personal safety issue, I'm not that concerned about getting COVID since I'm immunized. From a public health perspective, I'm very concerned about the people who are not immunized becoming factories of the next COVID variant that might be undetected by the current antibodies generated by the vaccine."

Ultimately, "Some of us have remained more cautious than others, but I would certainly urge everyone now to get your mask out of that drawer and put it back on," Schaffner says.

Should vaccinated people be getting tested?

Regularly testing is not recommended for people who have been vaccinated against COVID-19 unless they have symptoms, Adalja says. "However, the new guidance does state that vaccinated people who have been significantly exposed to COVID get tested three to five days later," he points out.

Testing is likely to be more important as we get into cold and flu season, Schaffner says. "As the weather gets cooler, we may well be doing a lot more testing to try to distinguish between influenza, RSV and COVID, even in people who are vaccinated," he adds.

Nelson says that he's "very concerned about guidance about testing people who are fully vaccinated," calling it "terribly regressive." He adds, "There's really no data that says they're infectious — just that they have the virus."

Many places require vaccination proof or a negative COVID-19 test result within 72 hours for public events. Why 72 hours?

Lollapalooza is the latest festival to adopt this rule, but Adalja says that there's nothing magical about 72 hours when it comes to COVID-19 risk. "The 72-hour window is more a function of how quickly people can get test results back," he says.

Schaffner agrees. "Everybody is trying, in their own ways, to take these general recommendations and apply them in a way that seems to work reasonably well," he says. "Testing unvaccinated people within 72 hours of attending a concert is not perfect, but it will screen out some people who are positive. It's an attempt to make things lower risk but not 'safe.'"

How can you stay safe at larger events like weddings this summer?

Many couples who put off wedding plans at the height of the pandemic are now moving forward with them — but the modified CDC guidance has caused some confusion. "If you're attending a large event, make sure you're vaccinated and urge the organizers to only admit vaccinated individuals," Adalja says. "The chance a fully vaccinated person has a significant breakthrough infection is very low."

Schaffner agrees. "If not everyone who attends is obligated to be vaccinated, why haven't the bride and groom insisted on that?" he says. "You need to know the policy, including whether there will be an encouragement that everyone will be masked." Then you can make a decision about your personal risk based on that.

Are you at risk if your fully vaccinated partner doesn't want to wear a mask?

Schaffner says that there's "not a single formula there," pointing out that this is something couples will "have to work out.” Still, he adds, "if you're both vaccinated, that's a very good start."

How can regular people assess their risk?

Schaffner recommends looking at your local data about COVID-19 cases for insight. "No community is COVID-free, but some have more transmission than others," he says. "Also, who are you and what are your underlying health conditions? All of those things should factor into your personal sense of how assiduous you want to be."

Just keep this in mind, according to Adalja: "If you're a regular person and fully vaccinated, your risk of any significant disease from COVID is vanishingly small."

What else should I keep in mind about the changing mask guidance?

Schaffner urges people to remember that the CDC is trying to alter guidance to match the latest data. "They're responding to changing circumstances," he says. "We have to be flexible. It's the reality."

But Adalja isn’t convinced that the new guidance is necessary for many fully vaccinated people. "I think the CDC guidance for masked individuals isn't justified," he says. "This is a pandemic of the unvaccinated, and the marginal — if any — benefit that having vaccinated people wear masks in a high-prevalence setting is not going to have much impact."

He's also concerned that the return of masks in indoor settings will further discourage people from getting vaccinated. "It will undermine confidence in the vaccine and probably not make much of a difference to the people who have refrained from being vaccinated thus far — they could now see no reason to be vaccinated if it doesn't change anything for them," he says.

Russo urges people to keep this in mind: "The honor system has failed. Mask mandates will hopefully get the unvaccinated to wear masks. But, at the end of the day, vaccination is our ticket out of this."

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