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Podcast: What to make of CDC’s new masking guidelines

This episode of 'Show Me the Science' details how changes in recommendations for masking will be implemented at the university and elsewhere

May 19, 2021

A new episode of our podcast, “Show Me the Science,” has been posted. At present, these podcast episodes are highlighting research and patient care on the Washington University Medical Campus as our scientists and clinicians confront the COVID-19 pandemic.

After recently announcing that vaccinated people could safely take off their masks outdoors and gather in small groups with other vaccinated people indoors, the U.S. Centers for Disease Control and Prevention (CDC) next decided that vaccinated people no longer need to wear masks indoors either. The new guidelines caught many by surprise, but William G. Powderly, MD, the Larry J. Shapiro Director of the Institute for Public Health and co-director of the Division of Infectious Diseases at Washington University School of Medicine in St. Louis, says the new guidelines provide evidence that, for many vaccinated individuals, going without a mask indoors is safe. He says vaccines against the virus are very effective and that although they don’t provide 100% protection, they come pretty close. But Powderly, also director of the university’s Institute of Clinical and Translational Sciences, says people need to remain aware that the pandemic is far from over, that the virus may fight back, and that the CDC may need to change its recommendations again at some point. For now, though, most vaccinated people are fairly safe without masks, he says. On the Washington University Medical Campus, masks still will be required in public areas in hospitals and in clinical areas.

The podcast, “Show Me the Science,” is produced by the Office of Medical Public Affairs at Washington University School of Medicine in St. Louis.



Jim Dryden (host): Hello and welcome to “Show Me the Science,” conversations about science and health with the people of Washington University School of Medicine in St. Louis, Missouri — the Show-Me State. As we continue to detail Washington University’s response to the COVID-19 pandemic, we look at some of the latest news from the Centers for Disease Control and Prevention, telling us that if we’re vaccinated, we don’t have to wear masks, even indoors. Dr. Bill Powderly is one of the directors of the Division of Infectious Diseases at Washington University, and he says the latest guidance shifts public health responsibility to individuals who now are free to choose the extent to which they want to protect themselves.

William G. Powderly, MD: We’re not telling people they’re on their own. We’re telling people, “You have a choice. You have a choice to get vaccinated, protect yourself or not.” COVID is still circulating, we still have 30 patients in the hospital. We still have four or five coming in every day, virtually all of them have not been vaccinated. So the virus will continue to have a toll on people, but it will be people who have chosen not to become vaccinated.

Dryden: Powderly says he, personally, still will wear a mask in some situations — at the grocery store, for instance. And he says now that it’s considered safe for vaccinated people to go maskless, it’s important that those who choose to continue masking not be stigmatized for it.

Powderly: By choosing to wear a mask you’re saying that, “I am not completely comfortable with the way the CDC has outlined these guidelines,” or “I think that there’s still some risk to me.” That’s a perfectly legitimate choice. I think one of the things that we will see in the United States over the next year or two years or more is that mask-wearing will become much more common.

Dryden: Powderly says many people were surprised by the CDC announcement that fully vaccinated people now can safely go without masks indoors, even when around others.

Powderly: For people who are fully vaccinated, you are much more significantly protected than you were previously, and the emerging evidence is that you are well protected both for yourself and from the likelihood of transmitting. So what the CDC has said is that in many circumstances, people who are fully vaccinated no longer need to wear masks.

Dryden: When I first heard the news about masking no longer being needed indoors for vaccinated people, I thought to myself, “How am I going to know who’s vaccinated?” What was your first thought?

Powderly: Very similar. I think most people were surprised by this; it came out quite unexpectedly. I think people are very comfortable, right across the board, with the advice the CDC has given that, outside, masks are not necessary for vaccinated individuals. The risk of acquiring COVID in the outdoors is very small, and the risk of transmitting it on is smaller still, and so that’s a really comfortable zone for people. The situation for indoor environments is a little more complicated. First of all, as you said, you don’t know who is vaccinated and who is not, and we can’t assume that not wearing a mask is a statement from an individual that, “I am vaccinated.” And we don’t currently have proof of vaccination that is acceptable and secure. So I think when we look at indoor environments for people who are not vaccinated, it remains a judgment call. I think what the CDC is saying, though, for vaccinated individuals, many indoor circumstances are quite safe. As a consequence, they may choose not to wear a mask and not worry much about the risk of infection. The corollary of that, however, is that if they choose to wear a mask, that’s their choice. Because I think that we’re moving now from a mass community guidance to much more of an individual choice and individual responsibility perspective.

Dryden: Masks are still required on trains and planes and buses. So although the announcement to me represented a very sudden change, part of me feels like maybe the implementation of that change is going to be much more gradual.

Powderly: I think it’s important for everybody to realize that COVID hasn’t gone away. We’re still seeing infection in the community. The vast majority of that infection is now occurring in people who have not been vaccinated, but there is still circulating virus. We’re entering into a phase of the year, for a respiratory virus, where there is less circulation, particularly because people are more outdoors, but indoor settings remain the major risk for people. So what I think you’re going to see is that this will be nuanced. People will make choices based on their own individual risk in situations where there’s a lot of exposure to other people. Many people, even if they’re vaccinated, will choose to remain protected, or to maximize their own protection. Certainly, the CDC guidance gives exemptions for certain circumstances, including public transport, but also for hospitals. Our perspective in the hospital would be that we still are in an environment where we have many vulnerable patients. We can’t guarantee that all of our patients who have been vaccinated have responded appropriately to the vaccine because many of them have some degree of immunosuppression. That is, they have a disease, or they take medications that means their immune system isn’t fully functional. Many of those will respond to the vaccine but not all. And we don’t know who. Many of our patients, when they come in, we won’t know before they come in what their vaccine status is. So we’re going to recommend and continue to recommend that in the hospital clinical environment and in all public spaces that lead to public traffic, that people should continue to wear masks. I think many businesses will make similar decisions about the risk to their employees and the risk to their customers. In other circumstances, the decision will be up to the individual. I think it’s really important that we don’t do the reverse of what we did, which is stigmatize people who choose to wear a mask. By choosing to wear a mask, you’re saying that, “I am not completely comfortable with the way the CDC has outlined these guidelines,” or “I think that there is still some risk to me.” That’s a perfectly legitimate choice. I think one of the things that we will see in the United States over the next year or two years or more is that mask wearing will become much more common, particularly in the winter, particularly in respiratory virus season. And not just for COVID because what we learned this year is that we don’t have flu epidemics when people are wearing masks and being more careful when they’re around other people. So I think many of us will choose, particularly in crowded indoor settings, to continue to wear masks.

Dryden: What about people like transplant patients? I know many are vaccinated, but not all are getting a robust antibody response. What do those people do?

Powderly: Jim, you’ve outlined the absolute reason why we can’t have black-and-white rules. Transplant patients are a very vulnerable group of patients. They’re vulnerable not only to external infections, but they’re vulnerable because their immune system leaves them at risk of many infectious complications. The best advice you can give to somebody in that circumstance is to be as careful as you can around others and to continue to wear masks and social distance and hand hygiene, as you had before. We don’t know for sure yet whether for individuals in that circumstance the vaccine is completely ineffective. There is work being done here and elsewhere, looking at the degree of the immune response. Just because you don’t detect antibodies doesn’t mean that there might not have been an immune response, but definitely it is less than somebody who hasn’t had a transplant. Until we find better ways of preventing SARS-CoV-2 in that circumstance, the best advice we can give to people such as that is to continue to be careful.

Dryden: I’ve heard for many months that a reason that vaccinated people needed to continue masking was because the virus could mutate and change after infecting people, and that as long as the virus was raging in places like India and South America and other parts of the world, even vaccinated people might eventually need protection from variants as the virus continues to mutate and evolve.

Powderly: That’s a great question. I think one of the things to recognize is the guidance is for what’s happening right now. Right now, we have vaccines that are extremely effective against all of the variants of COVID that are circulating in the United States, including some of these mutants. The vaccines still work, and they work very effectively. They’re really effective against preventing disease and very effective against preventing transmission. But they’re not 100% effective, and people have to remember that there is still a risk, which goes back to the fact of having a personal evaluation of the situation and deciding whether I want to wear a mask or not. But, as I said, it’s a moment in time. Come the fall of next year when we’re back into winter virus season, COVID will still be there, and it will be very important for people in this country to look at what’s going on not only nationally, but in their own region because it may well be that there will be local outbreaks that will need a local response, or there may be further mutation and change in the virus that would mean that we need to develop another vaccine, for example, or a different approach. This has not gone away. I think we know that we’re going to be living with it for quite some time, if not many years. But what we are at a situation in, is that the pandemic, at least in the United States at the moment, is under control. We’ve come a long way. It’s been at a huge cost, over 600,000 lives lost and many people with long-term consequences of this virus. But it’s a tribute to the science that has gone into it that we actually have effective vaccines for well over 100 million Americans already and many more across the world.

Dryden: The vaccine, I mean, it’s borderline miraculous that it was so quick and that it was so effective. Do you think that this is enough of a carrot for people, that they’re going to go and get the shot? I mean, I guess that’s what the CDC is hoping in announcing this.

Powderly: I think there are a couple of motivations. The first is psychological. This epidemic has taken a huge toll on people. The sense of isolation. The sense of being constantly worried about a hidden threat that you can’t see. The effect on families, on grandparents not seeing their grandchildren. The second thing is that I think part of the motivation is indeed to give a premium to vaccination, to show people that there is an advantage to being vaccinated. You can, in fact, get back to a more normal life. You can socialize more with people without having to wear a mask. And I think the other part of it is, is a movement toward making much of this an individual responsibility. It’s your choice to get vaccinated, and if you get vaccinated, there are advantages. Not only does it protect you against the disease, but also you can do things more easily that were challenging for you a few weeks ago.

Dryden: But nobody’s checking.

Powderly: That’s right. We’re trusting people. That is a challenge from a public health perspective, you’re absolutely right. But I think one of the things you can say is that challenge has always been there because of the unfortunate way masking became politicized in the United States. And that was one of the worst things that happened to public health in the last year, is that instead of it being science-driven, it became politically driven, and we need to overcome that and get away from that and really let science tell us. And the science is telling us: If you’re vaccinated, your risk of developing serious disease and dying from it is extraordinarily low.

Dryden: But I just wonder why this wasn’t a phased announcement, why it wasn’t, “OK, we’re shooting for June 15th,” just to give people a chance to adjust to the new reality. It just seemed like, “Boom.”

Powderly: I do agree that the suddenness was a surprise. And I do agree that many people would have been more comfortable with a phased announcement. But on the other hand, I think the reality is that the science is telling us that vaccines work. They’ve been telling us vaccines work for some time. Some people were impatient with the CDC for not updating its guidelines, so I think they were in a rock and a hard place, to be quite honest with you. I will go back, though, to the point I made earlier. I know, myself, that I will still be careful in crowded situations. I will still wear a mask in grocery stores. I will still, if I’m going into a restaurant, look at how they’ve set it up and make a decision perhaps as to whether I would only prefer if I’m sitting outdoors for a while. That’s a personal choice, and it may not reflect the fact that, objectively, I know that my risk is extremely low, but I still want to minimize that risk even further. We will look at this not only on the basis (that) the vaccine works, and I know I’m protected, but I want to make absolutely sure. I think a lot of us have become quite OCD as a result of this year, and it will take a little bit, a while, for everybody to adjust. And I think that’s important because we may have to adjust again. We may have to make some other adjustments if there’s a rebound in the virus, and it’s important for people to realize that could happen. And that doesn’t mean that we failed, it means that the virus is fighting back. Mutations are the virus’s way of surviving. We have to just watch and see what happens.

Dryden: Washington University and many other schools are requiring students to be vaccinated next year. Does that mean that undergrad and law school and medical school go back to being the way they were?

Powderly: I don’t think we’ll ever get back to where we were, not completely. We won’t completely eliminate COVID, at least by this fall. We’re going to have to have some adaptations. We also have to think about the vulnerability of the people who they engage with, our staff, whether it’s teachers, whether it’s people who are cleaning their rooms, providing their meals, etc. It will require a lot of reflection before we say everything is going to be back, and we’re back in classes of 300 people, all sitting close together and coughing on one another.

Dryden: I had asked you earlier about some of those folks who are immunosuppressed, but part of me also wonders if this new policy is sort of telling people who are not vaccinated that suddenly they’re on their own?

Powderly: First of all, we’re not telling people they’re on their own. We’re telling people you have a choice. You have a choice to get vaccinated, protect yourself, or not. COVID is still circulating, we still have 30 patients in the hospital. We still have four or five coming in every day, virtually all of them have not been vaccinated. So the virus will continue to have a toll on people, but it will be people who have chosen not to become vaccinated. Our responsibility, from a public health perspective, is to make sure the vaccine is available to everybody who wants it and to hope that people who currently are hesitant will realize the advantages are all on their side if they get vaccinated.


Dryden: As the virus ravages other parts of the world like India and parts of South America, Powderly says it’s important to be ready to change things again in the future, to perhaps re-embrace masking and social distancing policies, even possibly to develop new vaccines to deal with viral variants. But he says at the moment in the United States, it appears people who are fully vaccinated are pretty safe, though the School of Medicine still will be requiring masks in many situations. “Show Me the Science” is a production of the Office of Medical Public Affairs at Washington University School of Medicine in St. Louis. The goal of this project is to keep you informed and maybe teach you some things that will give you hope. If you’ve enjoyed what you’ve heard, please remember to subscribe and tell your friends. Thank you for tuning in. I’m Jim Dryden. Stay safe.

Washington University School of Medicine’s 1,500 faculty physicians also are the medical staff of Barnes-Jewish and St. Louis Children’s hospitals. The School of Medicine is a leader in medical research, teaching and patient care, consistently ranking among the top medical schools in the nation by U.S. News & World Report. Through its affiliations with Barnes-Jewish and St. Louis Children’s hospitals, the School of Medicine is linked to BJC HealthCare.

Jim retired from WashU Medicine Marketing & Communications in 2023. While at WashU Medicine, Jim covered psychiatry and neuroscience, pain and opioid research, orthopedics, diabetes, obesity, nutrition and aging. He formerly worked at KWMU (now St. Louis Public Radio) as a reporter and anchor, and his stories from the Midwest also were broadcast on NPR. Jim hosted the School of Medicine's Show Me the Science podcast, which highlights the outstanding research, education and clinical care underway at the School of Medicine. He has a bachelor's degree in English literature from the University of Missouri-St. Louis.