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Podcast: New COVID-19 variants causing re-infections

This episode of 'Show Me the Science' focuses on easily transmissible variants causing another wave of COVID-19 infections

August 3, 2022

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A new episode of our podcast, “Show Me the Science,” has been posted. In addition to reporting on the state of the COVID-19 pandemic, these episodes feature stories about other groundbreaking research, as well as lifesaving and just plain cool work involving faculty, staff and students at the School of Medicine.

Infections and hospitalizations are rising again. During this latest wave of COVID-19 infections, many fully vaccinated people are getting sick, as are people who previously were sick with the virus, even those infected in the very recent past. The new strains of omicron — BA.4 and BA.5 — have stricken some well-known, fully vaccinated people, including President Joe Biden and Dr. Anthony Fauci.

In this episode, we speak with William G. Powderly, MD, the J. William Campbell Professor and co-director of the Infectious Diseases Division at Washington University. Powderly says the recent increases in cases and hospitalizations are a reminder that, even after two-plus years, the pandemic is not over.

Vaccines seem to protect many people from serious disease, but infections among those who are fully vaccinated have become more common as BA.4 and BA.5 have become the virus’s dominant strains. Rachel M. Presti, MD, PhD, an infectious diseases specialist and an associate professor of medicine at Washington University, is among those testing new vaccine boosters engineered specifically to target those new strains. Presti, medical director of the university’s Infectious Diseases Clinical Research Unit, says it’s still too early to be certain but that the updated boosters seem to provide better protection than the currently FDA-approved vaccine. Of course, how long protection provided by the updated booster might last may depend on how quickly the virus continues to evolve.

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. During the first two years that we produced this podcast, we focused entirely on how School of Medicine doctors, researchers and trainees responded to the COVID-19 pandemic. Now, as the pandemic, we hope, is receding just a little, we also are reporting on some of the other research, lifesaving and just plain cool work being done at the School of Medicine. But we’ve begun to wonder whether the pandemic really and truly is receding. The number of infections has increased. Hospitalizations are up in much of the country and in our nation’s capital.
Karine Jean-Pierre: This morning, as part of our routine screening program for the president, the SARS-CoV-2 virus was detected by antigen testing. This result was subsequently confirmed by a PCR test. President Biden is currently experiencing mild symptoms, mostly a running nose and fatigue with an occasional dry cough, which started yesterday evening.
Dryden: That’s press secretary Karine Jean-Pierre telling reporters in the White House briefing room that since it began infecting people a couple of years ago, SARS-CoV-2 is now two for two in infecting U.S. presidents. And President Biden isn’t the only high-profile person in Washington who recently has had COVID-19.
Anthony Fauci, MD: My symptoms were mild throughout the entire — I mean, I never stopped doing anything that I was doing. I did all of my work virtually. So I wasn’t sick. I had a runny nose, I had a little bit of sore throat. I had a fever for about a day or even less, and that responded very well to Tylenol. And then I didn’t take any Tylenol and (it) was gone.
Dryden: Dr. Anthony Fauci and President Biden are among millions of people who have been caught, so to speak, by new highly infectious variants of the SARS-CoV-2 virus. Dr. Bill Powderly is the co-director of the Division of Infectious Diseases at Washington University School of Medicine and the director of the university’s Institute for Public Health. Although he says no one is predicting another wave, anything close to what we had last winter, he says the recent infections of the president and Dr. Fauci and probably lots of our friends and family members is a reminder that even now, more than two years after it began, the pandemic isn’t over.
William Powderly, MD: I think it was always a fallacy to think that the virus had gone away. It hadn’t. In fact, the number of infections we’ve been seeing is as high as it ever was. The real difference that has happened in the last two years is that vaccination led to the risk of dying from this disease, becoming severely ill from this disease, to be reduced enormously. But the virus has evolved incredibly. It is now the most infectious virus we’ve ever encountered. We used to say that about measles and chicken pox. But this variant of coronavirus that’s circulating is even more infectious than those viruses. Many people who are vaccinated and also people who perceive themselves at risk continue to take precautions. But even people who take a lot of precautions — and I have no doubt that Dr. Fauci and President Biden were in that group — are still liable to come into contact with someone who is infectious and become themselves infected. But we shouldn’t minimize this. Two thousand Americans are dying every week from COVID, even still.
Dryden: As you say, this is an infectious strain, BA.4, BA.5. But at the same time, we’re being a lot less careful as a country.
Powderly: There’s no doubt that the amount of infections that occur relate to both the natural infectivity of the virus and the mitigation efforts that we take from a behavioral perspective. The real fact, though, is that people are tired, and they want to get back to normal. And for most people right now, COVID is an irritant and inconvenience, but not a threat to their lives or the lives of their families. And they perceive it as that and are willing to take the risk. We’re very insistent in the hospitals, because we have so many vulnerable people, that people continue to wear masks in the hospitals, and many people will extend that to grocery stores, other places. But for the majority of people, they’ve accepted that it’s not a life-threatening infection right now. That said, I think should the virus change even further and should we have a perceptible surge, it will change people’s behavior again. We know reducing your own personal risk — not going into crowded environments, wearing masks when you are in them — will decrease the infection. We have shown that there’s lots of evidence for it.
Dryden: But what have the new strains taught us about the effectiveness of vaccines? It’s been true since the appearance of new variants that the vaccines developed against the original strain of SARS-CoV-2 were targeting a virus that, in some ways, didn’t really exist anymore. The vaccines continued to provide protection against hospitalization and death. But as the virus has evolved and the current strains of omicron called BA.4 and BA.5 have become dominant, more vaccinated people, like the president and Dr. Fauci, are getting sick. It’s also true that more people who already have been sick with COVID-19 are getting sick again.
Rachel Presti, MD, PhD: I’m Rachel Presti, an associate professor of infectious diseases in internal medicine.
Dryden: Dr. Rachel Presti is one of Washington University’s principal COVID vaccine researchers. She’s involved in studies of new vaccines that include not only the original coronavirus variant but also have been updated to try to provide protection against the more recent strains.
Presti: The companies have been trying to keep up, and they’re not doing any better than the rest of us with keeping up with a number of new variants. And so the vaccines that they have tested recently have had the original omicron sequences. The FDA is saying they want the BA.4, BA.5 sequence. So those vaccines are just being tested. The question really still is how effective are they? But they do seem to have a better response.
Dryden: But with this BA.4, BA.5, a lot of vaccinated people have gotten sick. Often it’s mild illness, but what’s called “mild illness” can lay you up pretty good for at least a few days. We’ve also seen a whole lot of folks re-infected who may have had it weeks or months ago, which begs the question of whether we even can be protected from this variant, the BA.5 or the BA.4.
Presti: I think we have to redefine maybe what we mean by protection. And I think what we’re seeing is probably what’s been seen with lots of viruses. Over time, they evolve and people get infected, and they develop some immunity, but they don’t necessarily develop sterilizing protective immunity, where you immediately shut down the infection. Your immune system doesn’t kick off until the virus actually gets in. So your immune system isn’t external to you, it’s internal to you. So the virus has to get in. So it’s very, very unusual for you to be able to say that you’re completely protected by your immune response. What you always were protected against is severe disease. When you move a virus into a new population where there’s no immunity, you get very severe disease. This is what happened when the Europeans came to the U.S. and colonized, and a lot of Native Americans were originally exposed to all sorts of pathogens that they’d never been exposed to. They got very severe disease, much more severe than you would see in Europe, because people, even though they could still get sick, they had some level of immunity, and the population had some level of immunity. So I think what we’re still unsure about is when do we get to a point where we say, “This is an infection that we know how to deal with, that we’re comfortable with, that we know when should you stay home? When should you go back to work? When should you wear a mask? When should you take it off?” We’re still trying to figure that out, I think. And I think we’re seeing extremes on either side, people who are afraid of what is likely to be minor infections and people who are no longer taking it seriously at all, when it still is causing some severe infections in certain populations.
Dryden: Presti says several things are going on at once. Immunity from vaccines tends to decline after several months. Plus, vaccines that were developed to fight prior strains of the virus are becoming less effective against the newer strains. At the same time, those new viral strains like BA.4 and BA.5 that are becoming dominant are more contagious. And along with all of that, more people are going back to their normal lives at a time when, in most of the country, masks are no longer required in stores or at concerts or at movies or on buses or planes. More than a year ago, many of us thought vaccines would lift the world out of the pandemic. But Powderly says vaccinated people remain at risk.
Powderly: It’s lower in people who have been vaccinated. It is very hard to imagine that people would be able to completely avoid it.
Dryden: Maybe this is a poor metaphor, I don’t know. But you come into a dark room, you turn on the light. The sun comes out. You can turn the light off. But if it gets dark, again, maybe you turn the light back on. Should we be thinking about some of the mitigation efforts the same way?
Powderly: Absolutely. I think what you’re saying is exactly what many people will do in their own personal lives. What is really hard, however, is for communities and societies to do that, because that is not only a personal decision, it becomes a political decision. And unfortunately, what has happened here, particularly, but in some other countries as well, is the whole notion of public health and public responsibility has become entwined in politics. And as a result, people are making decisions, are having decisions made for them, that are not necessarily evidence-based.
Dryden: I have another theory, and I’ve got nothing to back this up except a feeling, which is that a lot of people probably would wear masks, but because it’s not mandated, they think it’s safe not to.
Powderly: I don’t think it’s crazy to think that way. We mandated masks in the clinical environment, in the hospitals. Part of it is the messaging. Part of it is the fact that we’re very clear that this is not only to protect individuals who are working in this space, but it’s also to protect the vulnerable patients who can’t otherwise protect themselves. I think consistent messaging that makes sense does appeal to most people. The challenge with mandates are that we will always have a number of people who will resist mandates, not because they aren’t the right thing to do, but because it is somebody else telling you what to do. That said, I think, where you can see issues that mandates, I think, could well come back are things around masking in public transport, as an example. So recognizing that there are certain circumstances where a mandate makes absolute sense because of the fact that everybody recognizes that this is a crowded environment where you have no control, you have to be there. And so I think those sort of situational mandates are more acceptable than others.
Dryden: Listening to the radio this morning, I heard someone say, “Well, if the president got this, if Dr. Fauci got this, is it worth getting a booster shot?”
Powderly: Absolutely it’s worth getting a booster shot. We know that immunity from the original vaccine is waning. We also know that it is less effective against the variants than against the original. And 90% of the circulating virus in the United States right now is this BA.4, BA.5 variant. And we know that if you just got the original vaccine, it still works. It’s not quite as effective, and it loses its effectiveness every month. That’s why the FDA is recommending that the booster vaccine that will be available in the fall will be a combination vaccine of the original and a vaccine directed against the 4, 5 variant. This is not that different from what happens with an annual flu shot, where you’re trying to anticipate what is going to be the best vaccine, not for what happened three years ago, but for what’s happening now.
Dryden: And Presti says what’s happening now is that doctors and scientists are again racing to get a new vaccine ready so that next fall and winter won’t be a repeat of what we had last winter when omicron first arrived.
Presti: This virus does seem to really be a winter virus. It’s not sticking to the schedule that we want it to and staying a winter virus insofar as we are still seeing infections all the way through the summer, and we do tend to see this kind of rise in late summer, but it tends to be kind of a smoldering level of things, and what we see are these big spikes of infections in the winter.
Dryden: Neither Presti nor Powderly have had COVID-19 themselves, though both say members of their families have had it. Between all of the infections and all of the people getting vaccinated, it’s estimated now that more than 90% of the people in the United States have at least some immunity to the virus. Remember that idea of herd immunity?
Presti: We talked a lot about herd immunity, and we thought about that as a protective thing, and it is protective. It’s not protective against getting infected, but it is protective against a lot of people getting really, really sick. You want to think about how uncomfortable is it to wear a mask, how much does it hurt to not see grandpa? Those kinds of things we need to think about. We need to get on with our lives, and we need to actually figure out what do we need to do that is reasonable to do. And some of those are kind of small things that you could do. So if you don’t want to wear a mask the entire time you’re in a plane, wear a mask when you’re in the airport and boarding the plane until the pilot says, “OK, you can turn on your computers now.” That’s when the full sort of air circulation and the HEPA filters are all going, and your risk is actually pretty low. And then when they tell you you have to get ready for the plane to descend, put your mask back on. That will actually help a lot with decreasing your risk of flying. Or if the person next to you is coughing and spluttering and looks ill, then put your mask on then. Protect yourself as much as you can. The other thing is, if you have a big event that’s coming up and it would be really sad to miss it, be more careful going into that event. A lot of this has to do with the level of exposure. So my family, some of us have gotten infected, and some of us haven’t. And we’ve had situations where people living in the same house didn’t get infected. And it depends a lot on how much virus you’re exposed to. If you’re with somebody who has a very high viral load, they’ve maybe just gotten infected, they’ve got a lot of virus replicating in their upper airways and they’re coughing and they’re sneezing and they’re blowing out, that’s going to be a higher risk exposure because you’ve got more virus that’s hitting you.
Dryden: We’ve all got tests at home, and so what I want to know is, are those tests accurate enough to tell us what’s going on? Again, anecdotally, so many people I know that, “I wake up feeling bad, I take a test, it’s negative. I feel bad the next day, I take a test, it’s still negative. I guess it’s not COVID.” Third day, “Oh, look at that. It was COVID.”
Presti: That’s definitely something that I think all of us have heard. The rapid tests are fantastic at home. And if you feel fine, then a negative rapid test is “You’re good.” You do not have to worry that you’re going to expose somebody. So if you’re going to a dinner or you’re going to visit a grandparent, and you feel fine and you do rapid test and that’s negative, then you should feel very comfortable that you’re not putting someone at risk. If you don’t feel good, if you feel like you have a cold, even if you don’t have COVID, you’ve got something else, then you probably should not be exposing other people to that. If you, as an individual, don’t feel good, you should avoid exposing other people to that. And hopefully, that would be a lesson we would learn from this. There are mitigation measures you can put into place to avoid exposing other people to respiratory infections.
Dryden: Moving forward, Presti and Powderly both say it’s too early to tell what the coming months might look like and even whether the current variants will still be around then. They also say that although there is reason to hope that new vaccines will provide more protection against the BA.4 and BA.5 variants, it’s not clear yet how much more protection they might provide. The study so far looked fairly promising, but we’re still waiting on some data.
“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 introduce you to the groundbreaking research, lifesaving, and just plain cool work being done by faculty, staff, and students at the School of Medicine. If you’ve enjoyed what you’ve heard, please remember to subscribe and tell your friends. Thanks for tuning in. I’m Jim Dryden. Stay safe.

Washington University School of Medicine’s 1,700 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, and currently is No. 4 in research funding from the National Institutes of Health (NIH). 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.