Amid confusion about reopening, an expert explains how to assess COVID-19 risk

A server wears a protective face mask while attending to customers amid the COVID-19 pandemic in Bethesda, Md., on June 12.
A server wears a protective face mask while attending to customers amid the COVID-19 pandemic in Bethesda, Md., on June 12, 2020.
Sarah Silbiger | Getty Images

Across the country, states are loosening the restrictions that had been put in place to curb the spread of COVID-19 — with varying results. New cases are decreasing in some states, including New York, Michigan and Colorado, while case numbers and hospitalizations have swelled recently in several states, including Texas, Arizona and Florida.

"Since the very first day of this pandemic, I don't think [we've been] in a more confused position about what's happening," epidemiologist Michael Osterholm says. "We just aren't quite sure what [the coronavirus is] going to do next."

Osterholm is the founder and director of the Center for Infectious Disease Research and Policy at the University of Minnesota. His 2017 book, “Deadliest Enemy: Our War Against Killer Germs,” was recently republished with a new foreword about COVID-19. Mark Olshaker is the book's co-author.

From the earliest days of the pandemic, the coronavirus has often been treated as a political issue rather than a public health issue — and much has been made of President Donald Trump's refusal to wear a mask in public. But Osterholm says that the risks from COVID-19 supersede partisanship.

"We will all know somebody — we will all love somebody — who will die from this disease," he says. "Eventually there won't be any blue states or red states. There won't be any blue cities or red rural areas. It'll all be COVID colored."

Osterholm says that face masks and physical distancing remain the best practices in terms of curbing the spread of the coronavirus. But he adds that "distancing" shouldn't mean cutting off all social contact.

"It's physical distancing. ... Don't socially distance. If there was ever a time when we all need each other, it's now," he says. "We need to start an epidemic of kindness right now to take on this pandemic of this virus."


Interview highlights

On anticipating a second, worse wave of COVID-19 cases

If cases should disappear over the course of the next six to eight weeks, or at least be greatly reduced, that is not necessarily good news. It surely seems counterintuitive that we would want cases to happen. I don't want anybody to get sick, severely ill or die. But if we saw a trough of cases in the next two months, I think that would really tell us that we're likely to have this big second wave, much like we would see with influenza, which could be much worse. I think the one factor that we must keep in mind at all times is that, to date, we have about 5 to 7 percent of the U.S. population has been infected with this virus. That's it. All the pain, suffering, death and economic disruption have occurred with 5 to 7 percent. But this virus is not going to slow down transmission overall. It may come and go, but it will keep transmitting until we get at least 60 or 70 percent of the population infected and hopefully develop immunity — or if we get a vaccine, that can get us there too. And so I want to be really clear: None of us are suggesting this is going to stop and go away, but if we see these starts and stops of the virus in between times, it's just that we don't know quite what's happening.

On the conflicting messages of some places reopening while others remain in lockdown

I think right now, most of the world — not just the United States, but most of the world — is quite confused about what to do or why to do it. And what I mean by that is, is that already I think we've seen pandemic fatigue set in, in the United States. Right around Memorial Day, the country was ready to say, ''We're done with this. We're unlocking. We're going to no longer do the kind of physical distancing that's been recommended. We should reopen the economy. Let's let the cards fall where they may." And I think to myself, wow, that's what's happened after 5 percent of the population has been infected. How might we ever get a population to do what it needs to do to reduce transmission to hopefully get to that vaccine before the disease gets us to that 60 or 70 percent level. That's going to be months and months. This is not what is going to last for a few more weeks. And if you look at influenza pandemics, they all did last for years, not for just a couple of months. And so I think that that's the challenge we have today is helping people understand: We've got to figure out how to live with this virus as much as we've had to painfully understand how to die with this virus.

On how COVID-19 transmission from surfaces is unlikely (and you can stop wiping down your packages)

Deadliest Enemy: Our War Against Killer Germs, by Michael Osterholm and Mark Olshaker
"Deadliest Enemy: Our War Against Killer Germs," by Michael Osterholm and Mark Olshaker
Hachette Book Group

One of the challenges we have with this disease, first of all, is making sure that we really have accurate and actionable information for the public. The public right now is so confused about what is safe and what's not safe. And one of the challenges has been is this idea that surfaces play a major role in transmission. We've looked very carefully at the data dating back for decades and research about these kinds of respiratory transmitted infections. And clearly, the surfaces play a very, very little role at all in transmission of this. I think we've gone way overboard relative to the disinfection and so forth, and we've made people feel very nervous about just opening a package, that type of thing. And I think that's been unfortunate. I mean, this is really all about air. Breathing someone else's air where the virus is present. It's much, much, much less about environmental contamination. I would not tell people not to wash your hands, because I deal with a lot of the diseases where hand-washing is very, very important. But I would also say no one needs to be frightened of their physical environment with this virus. It's the air they're breathing. And so if that gives people relief, I hope that's helpful. ...

I don't worry about food. I don't worry about newsprint. I don't worry about packages I get here. I don't worry about doorknobs and railings any more than I would during the regular cold season. [That's not] what's going to be the major challenge with this virus. ... It's the air that we share with each other that is critical. That's why distancing is so important.

On the risk of transmission from the outdoor Black Lives Matter protests

When it first occurred and we were watching it on our televisions, or being part of the protests themselves, it was clear that we were seeing all these people together for what had just been several months of hardly anyone together. And so the challenge of would this virus be transmitted in that environment was surely front and center for everyone in public health. Now, when we looked at that, we realized that it was outdoors largely, which in that case, the virus dissipates quite quickly into the air. If there's any air movements around, it literally blows the cloud away and, in a sense, disintegrates it. And so that would mean a lot less exposure to someone breathing the air near someone else who might be infected.

On the other hand, there were risk factors that we were concerned about, such as people who were exposed to tear gas and smoke that were coughing substantially. People yelling, shouting, whether they had a mask on or not, which we know can aerosolize the virus, getting it in terms of the air coming out of that voice. And then on top of that, we had individuals who were arrested, put in holding vehicles, sometimes for several hours before they were transported to the local jails, and they are then processed and put in a jail cell overnight. All of that would have likely increased cases. But as I said, we just haven't seen it yet. I think we're probably one to two weeks away from having more definitive answers, whether there was really an increase or not. And I think right now we are hopeful that we won't see a big increase in many of the cities that experienced these large crowds coming together.

On Trump's forthcoming indoor campaign rally in Tulsa, Okla., at a venue that holds 19,000 people

Right now, we have to understand that the single greatest risk factor we have for transmitting this virus is largely indoor air, where we're in large crowds, where we are sharing that air with the people right around us. Any activity that increases that, such as loud voices, shouting, singing, that we all know can enhance the virus being aerosolized or basically put into the air. So I would just say across the board, without regard to political party or why the event occurred, they shouldn't be occurring, if we're trying to reduce the risk of infectious disease transmission with this virus. It's just simply the last thing you'd want to do. It's almost like putting potential gasoline on a fire. I think it's fair to say that this should be a universal recommendation across the board that these kinds of events be avoided.

On how to assess risk based on general airflow

There's an old phrase in the environmental movement, "The solution to pollution is dilution." And actually in infectious diseases, the same thing is true. ... When you and I talk, we fill a room full of aerosols. If you actually had a special camera (that does exist and you can do this), you can actually see aerosols fill the room and these little particles after just 20 or 30 minutes of talking. So anything that moves air and moves that out more quickly is surely helpful. ...

Outdoors has its own natural, in a sense, air conditioning. I often hear people talking about the risk of going to the beach, and ironically, beaches are probably some of the safest places to go to if you're not literally cheek and jowl with someone, just because the wind is blowing all the time. It's creating, in a sense, kind of a cleansing of the air where that virus might come out. If you're in a building where the heating, ventilation and cooling system is not moving air very frequently, then that aerosol that that person is breathing in that conference room is going to build up over time. And so, yes, you are going to be a greater risk in that kind of a setting.

On why we need more data to understand the transmission exposure time

One of the projects that we're working on right now with a group of international experts is really attempting to measure the exposure that someone likely will have in a public setting, meaning exposure in terms of time and dose. I think people often think of transmission with this virus almost like tag: I get close to somebody who's infected — "Tag! You're now it." It's not at all. It is time related. We're working on this, and it may be that you need many minutes to be in an environment where this virus is in the air and you need to inhale it in, and the amount of breathing that you do at a certain level before you get infected, it's not just a yes or no. It's a threshold. So one of the things we're trying to do over the course of the next month is put out a series of documents that will actually give people just that kind of quantification you're asking for: If I open a car window, do I reduce my risk by fivefold? Tenfold? What is my risk at that point? What's my risk if I'm with 50 people versus 10 people? What are the chances of me actually coming in contact with the virus? We need this information badly. And this is one area where I wish the federal government had done much more to help supply that. In past public health situations, they did do that. And unfortunately, we're not seeing that with the same level of assistance right now as we have in the past.

On why he wouldn't recommend getting an antibody test

What we have largely is the Wild, Wild West of testing. The FDA has, I think, done a miserable job of overseeing the regulation and the authorization of antibody tests. Today, there's over 100 [tests] in the United States where somebody has just filed with the FDA that they are going to offer this, and that's all they had to do to be able to do it. We have seen a number of these tests that provide very, very poor results. ... If I were to test a large segment of the population today, half of all the test results that came back positive would actually be false positive — meaning they didn't really have the antibody. ... I would not use it at this point as a way of telling an individual patient that they did or didn't have COVID. The final piece is, of course, we don't know what antibody really means in terms of your own protection. We're worried that we're gonna start seeing people take different approaches to how they protect themselves if they think they're antibody positive.

Amy Salit and Joel Wolfram produced and edited the audio of this interview. Bridget Bentz, Molly Seavy-Nesper, Meghan Sullivan and Carmel Wroth adapted it for the web.

Copyright 2020 Fresh Air. To see more, visit Fresh Air.

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