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RHR: COVID-19: My Thoughts on Where We Are Now, and Where We’re Headed


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In this episode of Revolution Health Radio, I’m joined by health coach Will Welch in a discussion about COVID-19. We talk about the challenges we’re facing as a culture, whether we succeeded in flattening the curve, what the end of the pandemic may look like, and much more.

Revolution Health Radio podcast, Chris Kresser

In this episode, we discuss:

  • Will’s background and health coaching experience
  • The political, cultural, and psychological challenges we’re facing with COVID-19
  • Whether we are flattening the curve
  • The test, trace, and isolate strategy
  • The types of testing available for COVID-19
  • What we know about immunity
  • Signs and symptoms of COVID-19
  • What determines your risk of infection
  • Our emotional response to the pandemic
  • Assessing your risk comfort level
  • How the pandemic might end

Show notes:

Hey, everybody, Chris Kresser here. Welcome to another episode of Revolution Health Radio. I’m going to do something a little bit differently on the show this week. I’m going to be the guest. And I’ve invited Will Welch, who is an ADAPT-Certified Functional Health Coach and a National Board-Certified Health Coach with a background in organizational psychology, on to interview me. I want to do some COVID-19 updates.

We’re about three months in now and I think many of you have been listening to the podcast and following my emails, and perhaps some of my social media posts. So you may be aware of some of my more recent thinking on this topic. But I wanted to take the opportunity to put that all together and add some new thoughts based on new research that has been published just in the past few days, so that it’s really all in one place. And those of you who haven’t been keeping up on a daily or weekly basis with all the emails [and] social media stuff can get a sense of where I’m at in my thinking about this pandemic, both in terms of how things are likely to play out over the coming weeks, months, and years and how we can think about our own personal response to it. So I really enjoyed this conversation, and I hope it’s useful to you. Let’s dive in.

Chris Kresser:  Will Welch, thank you for guest hosting the show today.

Will Welch:  Thanks, Chris. Great to be with you.

Will’s Background and Health Coaching Experience

Chris Kresser:  We haven’t done this before. It’s something I’ve wanted to do for some time. I’ve definitely recorded some solo podcasts where I’m just talking about stuff, but I think it’s always more engaging to have a conversation and some back and forth. So I’m really looking forward to this, and why don’t you tell everyone a little bit about who you are and what you do and why you’re here hosting this podcast?

Will Welch:  Sure. Thank you. Well, first and foremost, I’m [an] ADAPT health coach training program grad. I’m an ADAPT-Certified Functional Health Coach and a National Board-Certified Health Coach as of February.

Chris Kresser:  Congratulations on that again.

Will Welch:  Thank you, [I] appreciate it. [The] program was such a good setup for passing that. So [I’m] really thrilled to have alphabet soup after my name now and NBC-HWC and A-CFHC.

Chris Kresser:  Yes. Lots of letters.

Will Welch:  But I actually got my start in research doing health psychology research. And so bringing that and my corporate human resources career together brought me to health coaching. And I thought it was a great fusion of everything I had done up to that point. And so that’s when I found the health coach training program. And now I’m also the enrollment manager for Kresser Institute. So [I’m] really glad to be here with you on this and have the opportunity to ask you some questions about COVID[-19].

Chris Kresser:  Great. Well, let’s dive in.

The Political, Cultural, and Psychological Challenges We’re Facing with COVID-19

Will Welch:  Great. So we’re almost three months into the COVID-19 pandemic in the [United States]. How are you thinking about the next stage?

Chris Kresser:  Oh boy, I think about it a lot. And it’s a big question. And it’s one that you can think about in a lot of different ways and from a lot of different perspectives. So I think a lot of the obstacles that we’re facing right now are actually psychological, emotional, behavioral, and even political and cultural, rather than just technical and scientific. Certainly, we have the technical and scientific challenges that we’re facing, like creating testing that is more accurate and can be deployed more quickly. Creating effective treatments or a vaccine. Creating more effective contact tracing strategies and technologies. All of that’s very real. I mean, we’re working on that, [and] we’re making progress. But the longer this thing goes on, the more I see that the psychological, emotional, behavioral, and then political and cultural obstacles may be even larger and more difficult to overcome.

So what I mean by that is, psychologists have known for many years that we respond to our reality based on our situation, things like our age or gender, our race or ethnicity, our socioeconomic status, our beliefs, [and] our health. All of these inform how we react to stimuli and information that are coming in and that determine our “reality.” And in psychology, there’s a concept called unmotivated cognition, which is the psychological realm that shows how people spin information and arguments in ways that give them the answers that they want. And what this means is that feelings and reactions tend to overpower facts. And we often will interpret facts in a way that helps us feel good or virtuous or like we’re doing the right thing. We’re on the right side of things. And this has been known for some time.

Like in the psychology of risk and decision-making, the psychologists who study this field [have] known for some time, as have economists, that we don’t make rational decisions just simply by calculating costs and benefits like a computer program would. It’s really more that our feelings, which are often unconscious, tend to be the primary drivers. And so I think we’re seeing this start to play out now, or [it] has been playing out for many weeks and will probably continue to play out. The most recent kind of example of this is the differing reactions to how we should be approaching COVID[-19] now. There are some who are strenuously arguing for reopening as fast as possible. And there are others who are arguing for staying in lockdown. And those arguments sometimes are informed by facts and science and other times they’re really much more driven by political, cultural, or psychological factors.

Will Welch:  And I imagine the longer this goes on, and here we are at about the three-month mark, the more that we aren’t rational actors compounds on itself and the more everything winds its way into all those factors that you listed, making decisions even more difficult.

Chris Kresser:  Absolutely, I think that’s the case. And I think it’s also the case in a country as large and heterogeneous as the United States, and where we don’t have a coherent federal policy that’s guiding decision-making, and instead we have responses that are broken down not just state by state, but even county by county. Like here in Utah, we have different counties making different decisions. And I’m not saying that’s not appropriate. The outbreak has impacted counties differently.

For example, in Summit County where I live, we’re still at a higher kind of threat level according to this color-coded scheme that the governor is using than some other counties because Summit County had a pretty significant outbreak early on. In fact, we had the highest number of cases outside of any county, other than one in New York. And that was probably because of [the] Sundance [Film] Festival, which attracts a lot of international tourism, and also just the ski resorts here, which attract international visitors. So yes, there’s some diversity in the response. But the longer this goes on, as you say, and the less coherent the response is, I think the more opportunity you have for these social, cultural, political factors to become a major driving force in how people are responding.

Are We Flattening the Curve?

Will Welch:  Yeah. So, as you’re thinking about the next stage, there are lots of things that have been brought up in the last three months. Things like flattening the curve and a lot of the basic stuff. How are you seeing some of that? Are we actually flattening the curve?

Chris Kresser:  We definitely flattened the curve, and that’s a very positive development and that was the initial goal of this. And as everybody knows by now, the purpose of flattening the curve was to reduce the strain on the healthcare system. It was not to end the pandemic. And I feel like there were some significant mistakes made by authorities early on in this pandemic. And when I say authorities, I’m not just talking about politicians; I’m talking about public health officials, pretty much anybody in any position of authority. They were not communicating effectively about the pandemic and they were not setting expectations properly. And they made a lot of mistakes that I think are coming back to haunt us now.

There’s an organization called the Center for Infectious Disease Research and Policy [CIDRAP]. Michael Osterholm is involved in that. He’s been interviewed on [The Joe Rogan Experience] and a bunch of mainstream media outlets. Really sharp expert in the field and I think he has a better track record than just about anybody in terms of predicting how this was going to unfold. He has a lot of experience with Ebola and other pandemics. And CIDRAP, this organization, actually published some communication guidelines that leaders should follow during a pandemic. And if you read through the guidelines, you see that in the [United States] especially, virtually all of those guidelines were flouted and not followed. I’ll just choose three of them as examples.

So the one number one was don’t over-reassure. So don’t tell people lies basically. Don’t tell them it’s going to be better than it really is. Because when you do that, there’s a tendency for politicians to want to do that, right? They don’t, no politician wants to deliver bad news, even public health officials don’t really want to deliver bad news. But it turns out that psychologically, if you reassure people and tell them it’s going to be better than it is, and then it’s worse, you lose trust. And I think that’s exactly what has happened. The public at large has lost a lot of trust in institutions and in leaders that they may have placed more trust in prior to the COVID[-19] pandemic.

The second one is to proclaim uncertainty. So this is, again, something that was not really embraced by leaders early on and maybe arguably still isn’t embraced. This is the worst pandemic we [have] faced, undoubtedly, since the Spanish flu pandemic of 1918. And there’s a lot that we don’t know. And this is clear to anyone who’s been following this. First it was don’t wear a mask, then it was wear a mask. First it was there’s no airborne transmission, and then it’s airborne transmission. And in an environment of that kind of uncertainty, it’s really important to be able to share that uncertainty with people and say, “Look, you know, we’re doing the best we can. There’s still a lot we don’t understand. We’ll keep you posted as we learn more.” But instead, there [was] a lot of unequivocal statements made early on. And then when those statements turned out to be false, once again, the public loses trust in the institutions and the leaders that are making those statements.

And the last one, there [are] actually six principles. But the last one I’m going to talk about is shared dilemmas. So this is related, of course, to not over-reassuring and proclaiming uncertainty, but if you have a situation where there’s not a clear winning choice, and you’re actually choosing between two not so great options, that’s a hard situation to be in. And again, that’s kind of a nightmare scenario for a politician. Right? We want to have, like, a great option to choose and offer [to] people. But if the options are really between, like, let’s say, shutting everything down and having enormous economic disruption and also death and all kinds of other consequences from that economic shutdown, or not shutting down and kind of [an] unfathomable level of disease and death as a result of not shutting down, that’s a big dilemma. Right?

And it turns out that being honest about those dilemmas and sharing them openly is the best approach rather than sugarcoating it and making it sound like “Hey, if we do this shutdown, things are gonna be great. We’re gonna be back to normal by Easter or back to normal by Memorial Day” or whatever. Again, if you do that, and it doesn’t happen, you lose trust. So I think these are some of the issues that have taken place. And I was going back to your original question. Yes, we flattened the curve, but it should have been clear from the start in all the communication that was happening that that was just the first step. Or let’s think about a baseball game. Flattening the curve is like the first inning. And now we’re at the end of the first inning, or maybe we’re entering into the, we’re in the second inning now. And there’s that [Winston] Churchill quote that’s been shared a bunch of times where he said, “Now this is not the end. It is not even the beginning of the end. But it is, perhaps, the end of the beginning.” And I think that’s exactly where we are now.

Will Welch:  Yeah, that puts it in stark relief as to where we are with respect to the situation. And thinking about that in the context of three months only being, getting into the second inning. I think that presents a landscape that people may not be thinking about.

Chris Kresser:  Yeah.

The Test, Trace, and Isolate Strategy

Will Welch:  Yeah. You talked about the psychological component of this and just shared some things around uncertainty and over-reassurance and trust. I think information has a lot to do with that. And many countries have been the most successful with COVID[-19] when they’ve employed a test, trace, and isolate strategy, which provides information about who has coronavirus and where that came from. How viable do you think that is here in the [United States]?

Chris Kresser:  Well, right now, we’re nowhere close. Let’s just start there. We are not yet in a place where we can effectively implement a TTI, test, trace, and isolate strategy like countries like Taiwan have, for a number of reasons. So again, this breaks down into technical and scientific challenges, and it breaks down into social, cultural, political challenges.

So starting with the technical and scientific, we don’t currently have the capacity to test a large enough number of people in order to make testing a cornerstone of how we get through this. Right now, we’re doing about 300,000 of the nasopharyngeal DNA swabs, where they stick a swab way up your nose and twirl it around a bunch, get some material and then send it off to a lab. We’re doing about 300,000 of those a day and our current capacity most experts estimate is about 500,000 per day. So we’re almost, we’re nearing the top of our capacity and that’s not even close to enough of the number of tests we would have to do to effectively implement TTI. Antibody testing is another issue.

We can come back, let’s come back to talking about testing in much more detail in a few moments. But I just want to kind of broadly answer your question first. So that’s the challenge with the testing part. Then the tracing and isolating part of the equation, I think is part technical and scientific challenge and part cultural and political. So a lot of the countries that have had the most success with these TTI approaches have been countries that are relatively homogenous; they have a high level of trust in government that the citizens of the country do, they have much smaller populations, and they’re much more likely to submit to measures that could lead to a significant decrease in their privacy.

And none of those things are true about the [United States]. So we have an enormous population that’s heterogeneous; it’s politically diverse and fractious. Security is a major concern, as it should be in the [United States]. And so, even if we were able to overcome the technical and scientific hurdles of an effective contact tracing strategy, I don’t think we have the political and social will to implement that on a broad scale here. And it has to be done on a broad scale for it to be effective. If it’s only done kind of half-heartedly, we might get some benefit, and I think we will get some benefit. But it won’t be, it can’t be the cornerstone of what we do as it has been in some of the other countries.

And then that brings us to isolation. That only works if you know who to isolate, right? And then it only works if people agree to be isolated. So again, those things have, that’s more of a, that has both a technical and a scientific and a social, cultural, political aspect to it. So I could summarize by saying I think TTI will be some part of the solution; it already is. We’re already tracing contacts in a pretty low-tech way right now. And it will be one of the elements that helps us to move through this, but not to the degree that it has led to really significant results in Taiwan and Hong Kong and Singapore and places like that.

Will Welch:  Yeah. And looking at those countries as an example, it’s really hard to draw an analogy here to us in the [United States]. The context is just so dramatically different for all the reasons that you just shared.

Chris Kresser:  That’s true. And that’s, I mean, that’s a good point that applies to many other discussions that are taking place right now. Like Sweden, for example, has pursued a different strategy. And even if that strategy that they’ve pursued, which is trying to get toward herd immunity by letting younger people who are not at high risk get infected, with the idea that if they reach a certain percentage of infection rate, the virus will die out on its own, whatever you want to say about that strategy, whether it’s good or bad, and there’s a lot of controversy about it, we can unequivocally say that even if it is effective in Sweden, that doesn’t at all mean it would be effective in the [United States] or in Africa or any other country or region, for that matter. Because [of] the demographics of the population, again, their level of trust in the government and willingness to go along with the recommendations. Their ICU and critical care capacity. Their access to PPE, personal protective equipment. All of that goes into determining whether that’s an effective strategy for a given country or even a given state or county in the [United States]. So we always have to keep that in mind when we’re talking about this stuff.

Will Welch:  Right. Yeah. And there’s those microclimates again, as you were mentioning. The county where you are versus the county where I am versus New York City. We have lots of little considerations for each of those places.

Chris Kresser:  Absolutely. Montana is not in New York City.

Will Welch:  No.

Chris Kresser:  You could be in Montana and really not even know that COVID[-19] is happening, like, if you were not following social media a lot and just kind of walking around there, you wouldn’t really know it. But in New York City, there’s no way to not know it. Your entire life has been turned upside down. And I think that actually is part of what has driven the polarization in this country in terms of how people are responding to this, not only along political lines, but also geographic and social and cultural lines. Because one person, your experience of COVID[-19], Will, is undoubtedly different than my experience, which is in turn different than our fellow co-worker who lives in New York City’s experience, which in turn is different than my friend in Montana’s experience. So when you have these dramatically differing levels of experience, that then, we talked about before, that our psychology of risk and decision-making is really highly informed by our experience, not just the facts. So that makes a big difference.

Will Welch:  Yeah, absolutely. You talked before about in the test, trace, [isolate] strategy wanting to come back to the testing piece. What are your thoughts on that?

The Types of Testing Available for COVID-19

Chris Kresser:  Well, there are two types of testing, of course. One is testing for current active infection. And the other is testing people to determine if they’ve had a COVID[-19] infection in the past. So let’s break those down into two categories and talk about each of them separately.

So first, recurrent infection. The most common test is the nasopharyngeal swab. We mentioned that earlier, it’s a very deep nasal swab. So they’re not just rubbing it around the outside of your nostril; they stick it way up there, twirl around. If you’ve never had one of these, they’re quite uncomfortable. Your eyes water and it feels almost like that moment where you’re about to sneeze, extended for several seconds. So I’m not trying to dissuade anyone from getting tested. So what they’re doing with that swab is they gather genetic material, and then they send it to a lab that looks for COVID[-19] genetic material, and then returns results in 24 to 48 hours. It’s possible it’s longer in some places and it’s quite accurate. No test is perfect, but there’s a relatively low chance of a false positive or false negative with that test.

The challenge is that that’s a long time to wait. If we want to get to a place where employees are showing up at the workplace and they get tested for COVID[-19] before they enter the workplace, there’s no way. They can’t just sit there and wait for 24 hours or 48 hours for their test results to come back. And so, even though that is an accurate test, it’s not really going to, it’s not enough to get us closer to resuming the new normal, post-COVID[-19] new normal. So, with that in mind, there are, of course, many companies that are working on tests that can return results more quickly and tell you if you have a current infection. So one is the Abbott ID NOW kit. This is the kit that has been used at the White House. So it’s a point-of-care [test]. It’s also a genetic test, but it can return results in anywhere between five and 13 minutes rather than 24 to 48 hours.

Now the problem with this is that some studies have shown pretty high rates of sensitivity and specificity, which means the sensitivity determines the chance of a false-negative result and specificity determines the chance of a false-positive [result]. And so one study, for example, found that you [have] no chance of a false positive with this test and only about an 8 percent chance of a false negative, which is pretty good. Definitely usable in the field. But then there was a big study done by NYU that showed much worse results. The chance of a false negative was almost 48 percent, which is really not better than a coin flip. You’ve got about half of, “Do I have it? I don’t know. Let’s flip a coin and find out.” The chance of a false positive was still very good. It was not 100 percent, or not 0 percent, but it was about [a] 1.5 percent chance of having a false positive, which is totally usable. And so that led to the NYU researchers who did the study and then some other experts in the field like Peter Hotez calling for that Abbott ID NOW kit not to be used and the White House should use a better technology. So there’s a lot of controversy about that.

There’s another one called the Cepheid GeneXpert. This is based on a genetic testing platform that’s been used to detect other pathogens before. So it’s got a history to it, and they just adapted it to be able to test for SARS [severe acute respiratory syndrome] coronavirus-2. And it’s another point-of-care genetic test that returns results in about 30 to 45 minutes. So not as fast as the Abbott ID NOW, and still maybe not super practical for certain applications where someone’s waiting for 45 minutes. But way better than two to five days, right? So this is an accurate test. The chance of [a] false negative is about 5 percent. So that’s 95 percent sensitivity. I couldn’t find a specific number for the specificity or chance of a false positive. But it seems to be very specific and accurate. So this seems to be emerging as maybe the best option in terms of a rapid response genetic test.

And then another company called Quidel just came out with an antigen test that got emergency FDA [U.S. Food and Drug Administration] approval, [which] returns results in 15 minutes. And it’s not testing for DNA like the other two, the Cepheid GeneXpert and Abbott ID NOW. It’s actually looking for viral antigens, which are proteins, viral proteins. So not the DNA, but the proteins. And this test, unfortunately, has some issues in terms of accuracy, as well. The chance of a false negative is about 20 percent. But the chance of a false positive is very, very low. So some people are arguing that the way that this test could be used is to quickly screen a whole bunch of people. And if someone does test negative, but they have symptoms that are highly suggestive of COVID[-19], we could then send the sample out for the more accurate DNA test that takes 24 to 48 hours to return results.

So, even though this test isn’t highly accurate itself, it could be used in such a way that, in a beneficial way. And certainly, if it finds someone who’s positive, that’s useful because the chance of [a] false positive is basically zero. So I think as we move forward, we’ll see a combination of these different types of testing platforms that are used in different ways. And we’ll get there. I’m optimistic that the testing will improve.

Will Welch:  I’m glad to hear that you’re optimistic. And I think getting creative with these strategies and using multiple tests to determine when they have different error rates sounds like a good step in the right direction. So I’m glad to hear that.

Chris Kresser:  Absolutely, yeah. We can’t let the perfect be the enemy of the good, right? We need to kind of work with the tools that we have and use them in the best possible way.

So that takes us to the second important component of testing, which is determining if someone has already been infected with SARS coronavirus-2. So that would be antibody testing. And this is blood testing. And unfortunately, as I wrote in an email recently, the antibody testing that we have currently is not very accurate to say the least. And the good news is I think that will change over time. And even in some settings, it’s already probably sufficiently accurate. But for the general population, it’s not accurate enough. And I’ll share a little bit about why. So let’s see if I can break this down. It’s so much easier to talk about this with visuals or write about it in email, because it gets pretty complex.

But we’ve talked about sensitivity and specificity of a test:

  • Sensitivity is the ability of a test to correctly identify those who have truly been [infected], so true infected. So the true positives.
  • Specificity is the ability to correctly identify those who have not been infected. True negatives.

So in a perfect world, all of our tests would be 100 percent sensitive and 100 percent specific, but that’s not the case. There’s really very few tests out there, if any, that I know of that are both 100 percent sensitive and 100 percent specific. So the additional complication is that even if a test has relatively high specificity, which means it’s unlikely to return [a] false positive, let’s say the specificity is 95 percent, which would generally be considered to be quite good in the realm of testing. It’s not that simple with coronavirus. Because when the overall percentage of people who’ve been exposed to the pathogen is still low, then a specificity of 95 percent could still lead to a very inaccurate test.

So if we imagine a hypothetical group of 500 people with let’s say 5 percent of the population has been infected, which is about the rate that most experts are assuming now, for the [United States], like, in general. Of course, it’s much higher in some places like New York City and Seattle. It’s much lower in other places like Montana and Wyoming. But let’s just assume, for the time being, that about 5 percent of the overall U.S. population has been infected. So that’s 25 out of those 500 people that are truly infected. But if the test has only 95 percent specificity, that means that in the same group of 500 people, it will [also] return 25 false positives. So if you get a positive result with that test, there’s basically a 50 percent chance that it’s accurate. Again, we’re at a coin toss. So that’s not very helpful.

Will Welch:  Yeah, and that example, I think, puts it in a stark contrast. Ninety-five percent sounds like a really high number, but when you use that example, and you say that basically it becomes the coin toss, yeah, that paints a different picture.

Chris Kresser:  And it’s very much determined by the background infection rate, as that example indicated. So in Summit County where I live, the infection rate is estimated to be more like 1 to 2 percent. So, in that scenario, the antibody testing would be even more inaccurate in an example that I just gave. On the other hand, if there is a place like New York City where the true infection rate might be more like 20 percent, then your chance of [a] false positive goes down. So there are two ways that we’re going to get out of this. Number one is, and I hope this is the way that it happens more quickly, is that labs will come out with testing that is even more specific, has a higher specificity. So there was, for example, last week, I mentioned this in the email that I wrote, a German lab called Euroimmun AG introduced a test kit that’s been approved in the [United States] that has 100 percent specificity. So that means virtually no chance of a false positive.

And so if we have a kit like that, that’s really helpful. Because if somebody, if you do test positive, then you know it’s accurate. And you can be relatively certain that, at least to the best of our knowledge right now, we can talk more about this in a minute, you’re somewhat immune from [coronavirus] or you have a higher chance of being immune and not being contagious. And that could lead to actually meaningful changes in your behavior. It might allow you to go back to work; it might allow for certain behaviors that you wouldn’t do if you didn’t know that you’d already had the virus and you were no longer contagious. So I think we need this antibody testing to get more accurate before we’re going to be able to start to resume activities, like having larger groups of people together and doing things that would depend on knowing what people’s COVID[-19] status is.

Will Welch:  Yeah, especially in the context of the challenges around tracing that you brought up before.

Chris Kresser:  Yes.

As the COVID-19 pandemic continues, we’re still learning a lot about symptoms, transmission, immunity, and more. In this episode of RHR, I discuss the newest developments around COVID-19 with health coach Will Welch. #coronavirus #covid19

What We Know about COVID-19 Immunity

Will Welch:  I think having these antibody tests, that’s huge. Now, this begs the question of any conversation around testing has to involve this discussion of immunity. What do we know about immunity to SARS-COVID-2 right now?

Chris Kresser:  Not enough, unfortunately. Yeah. There’s some conflicting data so far. On the pro side, there was a study actually published in Science. And they found, the researchers found T cells in the lungs of people with COVID, and that typically bodes well for the development of long-term protective immunity against the pathogen. On the other hand, we have a disturbing number of reports coming out of South Korea and China and other places, even in the [United States], of some people seeming to get COVID[-19] twice. People who tested positive for COVID[-19] were hospitalized, had a pretty serious case, then recovered, went home, and then ended up in the hospital again later only to test positive again with COVID[-19]. And so, some people believe that one or the other of the test results might have been wrong. So, as we’ve been talking about, there’s a chance of [a] false positive. So perhaps the first time they were sick, they actually had a flu and the second time was COVID[-19] or vice versa. Or some people are speculating that they never actually got cleared SARS coronavirus-2. And even though they became asymptomatic or had fewer symptoms, they were still struggling with it.

I think what’s clear at this point is, I’ve heard a number of virologists and epidemiologists express this, is that COVID-19 is one of the most diverse and I’ve heard words like “weird” and “bizarre” used to describe the virus and the disease that it causes. Because it really is a chameleon. It has so many features that we don’t even really yet understand. And I think this question of immunity and whether it’s lifelong, or whether it’s short-lived, or perhaps we get a sort of a certain amount of immunity to it, and we’re able to contract it again, but the second time it’s less severe. We don’t know the answer to these questions yet, and we really, we need to find out, because that, of course, the answer is going to drive many different decisions that we might make in terms of how to move forward in the safest way.

Will Welch:  And to go back to your analogy of just entering the second inning, only being three months [in] here in the [United States]. But globally, maybe in the fourth quarter of 2019 is when it started to emerge, we’re still collecting data from a scientific standpoint. It’s hard to answer questions like this with just a handful of data points in some areas for certain questions.

Chris Kresser:  Absolutely. As you know, that’s not how, the scientific process doesn’t work well under pressure, generally. And to be methodical and accurate with these processes takes time. And it’s incredibly frustrating for everybody involved because we don’t, we feel like we don’t have a lot of time. We want the answers now and we want to be able to make informed choices based on those answers, but it takes time to collect all of these data and make sense of them and also for the peer review process to happen. I mean, that’s another thing that’s difficult about the research that’s being published right now is that a lot of it isn’t peer reviewed. Because we’re trying to get it out as quickly as possible, which I think is the right approach. But we’re sacrificing accuracy for speed. And we just have to be aware of that and we have to not get too attached or wedded to any particular result, especially when it hasn’t been extensively peer reviewed.

Will Welch:  Yeah, you’re seeing a lot more preprints coming out of the non-reviewed journal articles. And I think we’re banking on widespread scientific literacy and understanding of the scientific process to accurately kind of contextualize that information. And I’m not sure we can do that.

Chris Kresser:  Yeah. It’s pretty clear that we can’t if history is any indication of the future. And we’ve already seen some pretty high-profile examples of where that can go wrong. The Santa Clara study was a seroprevalence antibody study that was done to try to estimate the rough prevalence of COVID[-19] infection or SARS coronavirus-2 infection in the population in Santa Clara. And I’m sure as many people recall, the study results came back suggesting a dramatically higher prevalence or incidence of COVID-19 in the population there. Something like 80-fold higher than was typically assumed.

And then those data that were published by the researchers who did that study have been roundly criticized and challenged by other researchers. But it made quite a big splash in the media at that time and it became even a rallying call for the group of people who believe that we’re overreacting to this virus and that really many more people are infected and don’t have any symptoms at all. And therefore, we should end the lockdown. So these are serious, these findings, and especially when, whether they’re right or wrong, they can lead to pretty significant policy implications.

Signs and Symptoms of COVID-19

Will Welch:  Yeah. Another area where things have shifted a bit is around our understanding of the signs and symptoms of COVID[-19]. And that seems to have been shifting recently. What have we learned about this?

Chris Kresser:  Again, that it’s weird or bizarre. I mean.

Will Welch:  Those are technical terms, right?

Chris Kresser:  Those are technical terms. Yeah. Like, it’s so heterogeneous and diverse. It really can present so differently in different people. I mean, starting with, for some people, zero symptoms. There are people who have tested positive who had absolutely no idea that they were infected by the virus. They had no clinical signs or symptoms of COVID-19 at all. Then on the other end of the spectrum, we’ve got very, very severe pneumonia and complications that lead to death.

So that’s a pretty broad presentation and you’ve got kind of everything in between. You have different populations being affected in different ways. As everybody knows by now, those with preexisting conditions like diabetes and heart disease have roughly [a] three-fold higher risk of death. People with obesity, even without any other kind of issues, have a much higher risk of hospitalization and that for some reason appears to be happening more in young people who are obese. We have no idea why. You’ve got generally kids who are typically not very affected at all and thought to be maybe even less contagious than adults. They tend to develop a pretty mild illness if they develop any illness at all.

And then on the other hand, we’ve been hearing over the last two weeks about a very severe multisystem inflammatory disease that’s developing in a very small fraction, fortunately, of children. And inexplicably, they develop this weeks after they initially contract the virus. So they have maybe mild illness for the first couple of weeks during the period that most people would be sick. And then, for some reason that we don’t yet understand, two, three weeks after that, they develop a very severe and potentially life-threatening multisystem inflammatory disease.

So those are just a few of the examples of how diverse this is. But from all the data that have been collected, we can come to some conclusions about what the most common presenting symptoms are. So, perhaps somewhat surprisingly, the number one symptom in terms of the minimum percentage of people that experience it is loss of smell or taste. And this is one that only became apparent a few weeks into the virus. In fact, I [have] a family member who, when I wrote, I did an Instagram video with an update about this symptom, loss of smell or taste, [said] that was the only symptom she was experiencing. And so it led her to go and get tested, and sure enough, she tested positive for coronavirus.

So this can be one of the main symptoms and, perhaps in some cases, the only symptom. Number two is cough, which is of course more typical and expected. And number three is fever. And then beyond that, you have shortness of breath, other upper respiratory symptoms like sore throat and stuffy or runny nose, fatigue, fairly common, muscle aches, headache, confusion, and gastrointestinal symptoms are a little more common than with some other similar conditions, up to close to 20 percent in some studies. But notably with kids, gastrointestinal symptoms seem to be much more common than in adults. And again, we don’t know why that is.

So those are the main ones. There are other bizarre, less common symptoms that are popping up that are confusing people. But I think statistically speaking, those are the main ones. What I would say is if somebody develops any type of flu-like illness where any of these symptoms are present, then I think it makes sense to get tested given the diversity of how it can present. If you’re able to get tested in your area and you do develop any of these kinds of symptoms, I think it makes sense to go ahead and get that test.

Will Welch:  Yeah, that does make a lot of sense. And I assume if you’re symptomatic to stay home. Like, that’s another good piece of advice, right?

Chris Kresser:  Stay home. Yeah, I mean, [in] some places, people are kind of still required to stay home. But even if you’re not, it’s yes, definitely a good idea to limit your exposure to other people and even limit your exposure to family members when you’re at home. If you can kind of set up a little quarantine area for yourself at home, especially if you’re living with people who are at higher risk, I think that’s a wise thing to do.

What Determines Your Risk of Infection?

Will Welch:  Yeah. And so you said, in a lot of places, people are still required to stay home. But many states are ending their stay-at-home orders. How can people stay safe as they venture out into the world again?

Chris Kresser:  Yeah, this is the million-dollar question right now.

Will Welch:  So you’re going to answer it for a million dollars, right?

Chris Kresser:  Well, we all want to know. And again, this is a difficult calculation to make and a difficult question to answer in a general way. Because the answer would be very different for someone who is 80 years old with diabetes and heart disease and who’s overweight than it would be for someone who’s 25 and healthy with no preexisting conditions. But in a general sense, I think we can break down the risk of acquiring SARS coronavirus-2 in a pretty simple formula. So the risk of infection is equal to the amount of exposure to the virus times time.

So the greater your exposure to the virus, like the more viral particles that you are exposed to and the longer you’re exposed to those particles, the higher your risk of infection. And there is, I think, a physician who is an infectious disease expert, Dr. Erin Bromage wrote a great article summarizing all the research that’s been done to quantify the different types of behaviors like coughing, sneezing, breathing, and how many viral particles and respiratory droplets those behaviors can produce. And thus, that actually helps us to determine that first exposure part of the formula.

So sneezing is the worst. A sneeze releases about 30,000 respiratory droplets traveling at 200 miles per hour, which it’s just so fascinating to learn about this stuff, even though it’s a little bit morbid. And the droplets from a sneeze are small. So they can travel all the way across the room and they’re also more likely to linger in the air, which is, of course, not what we want. And coughing is not quite as bad. Significantly less respiratory droplets, but still plenty to get you sick. So a cough releases about 3,000 droplets traveling at 50 miles per hour. And while most droplets from a cough fall to the ground quickly, they’re larger. Some can linger in the air for a significant amount of time. And Dr. Bromage pointed out that if a person is infected, a single cough or sneeze can expel as many as 200 million viral particles.

Will Welch:  Wow.

Chris Kresser:  Now, to put that in perspective, most experts estimate that as few as 1,000 viral particles are needed for an infection to take hold. So talking is also potentially problematic, especially loud talking. One relatively new study, which I mentioned in an email I wrote recently, found that talking can release about 1,000 droplets, and those can linger in the air for about eight to 14 minutes. And then breathing can release anywhere from 50 to 5,000 droplets. Most of the droplets from breathing fall to the ground quickly. So even though a breath may contain enough droplets to infect someone, the risk is going to be lower because the droplets fall to the ground quickly.

Now, just a side note here on masks. There’s been a lot of discussion and controversy about  whether people should be wearing masks. But I think if you understand this research that we’ve just covered, it makes it very clear why wearing masks can be enormously helpful even if they’re not N95 respirators or medical grade masks. Because when someone’s wearing a mask, if they sneeze or cough or even if they’re talking, the droplets that contain the virus are not going to spread out into the room and linger in the air. So this is, it’s a pretty straightforward thing. Wearing a mask is not about protecting yourself from the virus, it’s about reducing the transmission of the virus from any breathing, coughing, or sneezing that you might do, whether you know you’re infected or not. So I think this research sheds some light on why face coverings can be helpful.

Will Welch:  Yeah, and you talked initially about the social and cultural implications in the virus spread, as well. And wearing a mask also signals to other people this is something important to do. So I think it serves another purpose, as well.

Chris Kresser:  Yeah, it’s unfortunate that wearing, the decision about wearing a mask has become highly polarized and politicized. And we could look at it as we did, we looked at having a garden at home during World War II. There was this concept of victory gardens because there were food shortages. And people were encouraged to grow their own food in so-called victory gardens to support the war effort. We really came together as a nation. And women got jobs bolting airplanes together. There was a massive effort on a national scale, to fight a common enemy. In this case, it was the Germans in World War II.

And we could look at interventions like masks in the same way that it’s not about protecting yourself, although indirectly it becomes that. Because if you’re reducing the risk of infection and spreading, you are actually protecting yourself. But it’s really more about protecting each other, especially the most vulnerable among us. And it’s about fighting this common enemy of coronavirus. And that’s something that we could have potentially united around and done together. But now, the decision about whether to wear a mask is no longer one that’s made for social good, or to protect our health and the [health of the] people who we love. It’s really more of a political statement at this point. And I find that to be very, very sad.

Will Welch:  Yeah, it really is unfortunate. So back to, again, you mentioned a second ago the time and exposure components of that equation that Dr. Bromage talked about. And coughing and sneezing and talking having a certain kind of exposure level right away. What’s the time component there?

Chris Kresser:  So the time component is, well, let’s talk about time and even another aspect of exposure. So exposure also is determined by whether you’re indoors or outdoors. So you imagine kind of being stuck in an elevator that’s broken down with two other people with COVID[-19] for six hours. That’s kind of a worst-case scenario.

Will Welch:  Recipe for disaster.

Chris Kresser:  Yeah, you’re probably going to get COVID-19 or have coronavirus, rather. So on the other hand, if you’re outside and you’re taking a hike and somebody passes you, even if they have coronavirus, and even if they’re not wearing a mask, if they’re just breathing and walking, the risk, as far as we can understand, is relatively low in that outdoor setting. And there’s only, in fact, been a single outbreak of COVID-19 that’s been traced to an outdoor setting. So the good news in all of this, there’s always some silver lining, I think that means that taking walks or doing other outdoor exercise and even spending time with other people in small groups outside while maintaining appropriate social distance is likely to be pretty safe.

On the other hand, the highest risk of infection occurs when spending long periods of time with larger groups of people in enclosed spaces, and that’s particularly true when ventilation is poor. So indoor birthdays, parties, funerals, weddings, restaurants, offices and other indoor workplaces, conferences, churches, choirs, especially because when people are singing, [they] emit a lot of respiratory droplets and viral particles, and maybe theaters, these can all be sources and they have been of significant outbreaks. Then you have something that’s a little bit in between like brief trips to the grocery store, or other retail locations. So you’ve got a much larger space than an elevator, for example, or even a small office. And also, people aren’t spending as much time in a grocery store. So the amount of exposure is lower and the time is lower, and therefore, the risk of infection is lower. If you’re just going in there, doing some shopping, and coming out, especially if most shoppers are wearing masks, and you’re wearing a mask.

So then you think about things like should I go back to work, [and] should I go back to the gym? Those questions kind of depend. If your office is well-ventilated, adequate social distancing is maintained, people are wearing masks, and there are relatively few employees present, I think the risk is pretty low. But if ventilation is bad and there are lots of employees packed close together and masks are not being worn or required (so, for example, the recent outbreaks in meatpacking plants), then the risk is pretty high. With the gym, if the gym’s strictly limiting the number of people that are present and ventilation is good, and they and you are being vigilant about wiping down surfaces, the risk is pretty low, though higher than it would be with outdoor exercise. But other indoor activities where people are packed more closely together or you imagine something like jiu-jitsu, where you’re rolling around on the floor with someone, and then probably the risk is a little bit higher.

So I think if we take precautions, and we understand these data and the risks, then we can actually make informed choices that can allow us to at least resume some parts of our life. Today, for example, I went on a great mountain bike ride. And I view the risk of that as being extremely low. And it’s something that really supports me and makes me feel good and is a great self-care thing for me to do. So if you have access to that kind of thing, it’s great to be able to do that now. But I think it’s still too soon to do some other activities that we might love to do that pose a higher risk.

Our Emotional Responses to the Pandemic

Will Welch:  Yeah, and I think a lot of people will be glad to hear that as we get into, the Northern Hemisphere, anyway, spring and summer and all the activities that come along with that. So we’ve talked about the different ways in which this pandemic is affecting people, including the psychological aspects. But what about our emotional responses?

Chris Kresser:  Yeah, I mean, we’ve touched on this a little bit so far. But I think they’re really important. And as I said earlier, perhaps the most important factor here because they determine almost everything, at least on an individual level. How we approach risk, how we conceive of and contextualize this whole pandemic, what actions we’re likely to take or not take as a result of it. And then, of course, more day-to-day, personal responses to the pandemic. Like how well we’re able to cope with it or not and relate to the other people in our lives, our partners and kids and people we’re sheltering in place with or interacting with as we start to get back out in the world.

And one of the things that I’m noticing a lot as we go through this is that, I mean, we’ve been in a situation, Will, that you’re well aware of and we all are of increased polarization. And that doesn’t just apply to politics. It certainly does apply to politics, but it applies to many other areas of life. Health, certainly, you’ve got like the vegan versus meat eating debates that can become just absolutely vitriolic and vicious. You’ve got lots of discussion about gender and its place in society and how that’s approached, and that can become vitriolic and hateful.

You’ve got all kinds of topics where it’s difficult to hold a nuanced opinion, and certainly to express it without receiving a lot of negative feedback from both sides. And there just seems to be a lot of anger and rage in the social and political discourse of today. And there are a couple of social psychologists, I believe you know one of them, Will, Jennifer Lerner. And is it Dacher Keltner?

Will Welch:  Dacher Keltner? Yeah.

Chris Kresser:  Dacher, yeah, that did some research, and found that anger is closely associated with increased feelings of certainty, control, and optimism, which seems strange that anger would be linked in some ways to optimism. But what they think is when we feel very uncertain, information that helps us to direct our negative emotions toward a specific target, whether that’s a person or an institution or an idea, is psychologically comforting. And that sense of powerlessness that we have in a really complex and overwhelming situation makes it feel good to blame something or someone else, institutions or people, because it increases our sense of control and optimism, even if that sense is an illusion of control. And I think that’s partly why the response has become so highly politicized to COVID[-19] is that when we’re dealing with an invisible enemy, a very complex and overwhelming one, and when we’re in a situation where we’re not dealing with win-win choices, we’re dealing with lose-lose choices, humans don’t function very well in that situation. And we do tend to start blaming other people or other groups or other institutions, because that helps us to kind of catalyze our energy and direct it somewhere else.

Will Welch:  Yeah, that makes a lot of sense, and to be sitting with uncertainty, and you talk about nuance and vulnerability there, for now, we’re three months into this, that’s a long time to be sitting with so much uncertainty and vulnerability. And so it seems natural that people would gravitate toward a more optimistic state, and happiness is great when it’s associated with optimism. But you’re talking about the connection between anger and optimism here, and that’s created this situation, which is pretty combustible.

Chris Kresser:  Pretty combustible is a great two-word summary of the situation that we’re in. And it’s really easy to understand why we would make choices like this whether they’re conscious or unconscious. Because uncertainty is one of the most difficult experiences, I think, for human beings to tolerate. It really triggers that fight-or-flight response and we feel vulnerable; we feel like we can’t really respond effectively. Like, if you study animals in nature, for example, if an animal is threatened by a predator, and then escapes that interaction, the animal, at least in that situation, can run or fight. Because the enemy there is visible; it’s present right then and it’s kind of an acute situation that comes and goes relatively quickly. That kind of stress is not harmful necessarily over the long term because it just has a short-term impact, and when we can mount an effective response through fighting or fleeing, it has far less of an impact on us.

But studies of chronic stress have found that when we can’t fight or flee, when we can’t mount an effective response, and we feel helpless or powerless, the impact of that stress on our bodies and our minds is far more significant. And I think this is the place that we all find ourselves in. And so I think it’s a kind of biologically hardwired response to seek a target, again, a person, an institution, or something outside of ourselves that we can then fight because that actually helps us to process the stress that we’re feeling.

Will Welch:  Yeah, it takes all the uncertainty out of it [and] provides some clarity in the situation, as well.

Chris Kresser:  Absolutely. So it’s just something to be aware of, I think, for all of us and to guard against. And there are other ways of dealing with this kind of stress that are perhaps more productive, like getting support. We’ve talked a lot about mindfulness and meditation, gratitude journaling, all the tools we’ve discussed [and] I’ve talked about in webinars and emails and social media posts recently to build more resilience and grit. Because that’s what we need to get through the situation.

Will Welch:  Yeah, yeah. And you mentioned optimism before and it’s a great asset for balancing out stress when it’s tied to positive feelings and happiness. And there are many things to be optimistic about. You’ve talked about [them] in a number of your emails and podcasts, as well.

Chris Kresser:  Absolutely.

Will Welch:  So some things to be optimistic about might be travel and being able to see people again. So how should we be thinking about risk at a personal level when we consider things like travel, eating out, meeting up with friends, and maybe our summer plans?

Assessing Your Risk Comfort Level

Chris Kresser:  Yeah, it’s a great question. I think it’s important to understand that risk tolerance is very much an individual calculation. So one person might be comfortable with taking certain steps and doing certain activities that another person would be absolutely uncomfortable with, even if their circumstances are the same. Maybe they’re the same age, they don’t have any preexisting conditions, but they just approach these kinds of situations differently. And I think as a kind of meta comment, before we dive into specifics, it’s really important to understand and accept your own level of risk tolerance. Because I think that if you go too far outside of your own comfort level with risk, that’s going to generate its own stress. And what we don’t need now is additional stress.

Will Welch:  Yeah. And we talk about in the health coaching program a lot, meet yourself where you are. And I think that would be really good advice paralleling what you’re saying.

Chris Kresser:  Exactly. So let’s even take a step further back and talk about ways to think about risk from a public health perspective or at a larger population level.

So one of the failures in communication that we talked about earlier in the podcast was over reassurance on the part of leaders and health authorities, and not making it clear to people that we’re kind of in this for the long haul. That it wasn’t going to be a brief lockdown, followed by a return to complete normalcy. And along with that, I think, there’s been a failure of communication about how to even think about risk. It’s pretty clear now, I think we can all agree that we can’t get, there’s no scenario here where we can get risk to zero of getting coronavirus.

Even if an effective vaccine is developed, and even if effective antivirals are developed, and even if we shelter in place, and everybody just stayed home, we couldn’t get that risk down to zero. And even if we could get the risk to zero by, let’s say, sheltering in place and everybody being on lockdown indefinitely, it’s pretty clear that that would lead to other very big risks of economic turmoil or full-on catastrophe if it continued in lockdown mode, which then leads to death and disease from other causes and increase in suicide and so many other impacts that are just as significant as impacts, if not more so, than the impacts from COVID[-19].

So I think we really need to start with the recognition that there’s always some trade-off when we’re talking about risk reduction. It’s foolish and even dangerous, I would argue, to assume that there’s always a win-win option where you take this action, and all the problems are magically solved. That’s just not happening here. And so I think the better way to think about this is using a harm reduction model.

So harm reduction is a concept that has been employed in public health policies and approach[es] to addiction and even things like speed limit, which I’ll come back to in a moment. So let’s talk about clean needle programs. This is an approach that’s been used for decades now. And it comes out of the recognition that heroin addiction is a very serious addiction. And despite best intentions with group and individual therapy and treatment programs, many people are going to continue to use heroin. And so if they can be provided with clean needles, you’re not going to reduce the risk of issues that arise from heroin use itself. But you can then reduce the risk of disease transmission and other problems that can happen from using needles that are not clean. So that’s an example of a harm reduction model where we’re saying, okay, we may not be able to get the risk to zero here or reduce or eliminate harm, but we can take steps to reduce it.

I think speed limits are an even better analogy for what we’re going through right now. There are about 38,000 traffic deaths a year in the [United States]. And I think it’s pretty clear that if we reduce the speed limit to one mile per hour, just do a thought experiment here.

Will Welch:  That sounds fun.

Chris Kresser:  Yeah, we would probably eliminate almost 100 percent of those deaths, right? It’s pretty hard to die in a traffic accident if you’re going one mile per hour. And I mean, it sounds kind of ridiculous, right? But the fact is, we have already made a calculation where we have collectively agreed as a society to set a speed limit that will certainly lead to thousands of deaths each year. But we have agreed as a society to do that, because we recognize that if the speed limit was significantly lower and low enough to prevent all deaths, that would lead to many other undesirable consequences. How would food get delivered to [the] supermarket? Imagine trucks on the highway going one mile per hour. By the time the food gets there, it’s rotten in the stores and it would lead to …

Will Welch:  My nighttime food order would take till tomorrow to get there.

Chris Kresser:  That’s right. No two-hour Amazon Prime food delivery. Try two weeks or more. So, yeah, I mean, this is something we don’t, I’m sure few of us ever think about when we’re out driving [and] we see a speed limit sign. That sign is essentially a compromise, where we’re saying we’re going to accept a certain number of deaths per year, so that we can have a functioning society.

And this is where we are with COVID[-19]. Where we, in this reopening, we are saying this is almost certainly going to increase the number of people with serious disease and deaths. But we’re doing this because we need to have a functioning society. And you can, the analogy is that some of the measures that we’re going to continue to take in terms of promoting social,  continuing to social distance and advising that people wear masks and all the other interventions that we’ve talked about, that’s sort of like where we’re setting the speed limit. Right? And just as there’s a different speed limit on the freeway, as there is a different speed limit on a backcountry road or near a school, we’re going to have to set the speed limit to be different for reopening in different parts of the community, depending on what the level of risk is, and harm is in those communities.

Will Welch:  Yeah, I know [we were] talking about nuance before. There’s a lot of nuance that goes into how do you set that in a way that’s both opening stuff up and you don’t risk too much from the economy, but you don’t close it down and risk too much from a health standpoint? That’s a tough point to set.

Chris Kresser:  That’s the million-dollar question. With speed limit[s], we have at least research to guide us on where to set that speed limit to kind of maximize the social utility and minimize the deaths and accidents. But even that’s controversial, right? You have the Autobahn in Germany, [where] you’ve got an 80 mile per hour speed limit on some interstate highways, and then you’ve got [a] much lower speed limit in other states. And so I think we’re going to see a similar varied response in different states and in different places based on how they assign relative value to the social good of reopening versus the social, physical, and health harm of COVID[-19] cases and deaths. So there’s really no right or wrong answer here.

And what I wish is that just as I wish there was a more productive, constructive debate or discussion around nutrition choices, I wish there was a more productive and constructive discussion happening around this question, which I think is a very valid and interesting question that deserves real, kind of dispassionate discussion. But it’s turned into a very polarized and often political kind of statement rather than any true discussion. So that’s the 30,000-foot view at a population level in terms of thinking about risk and harm reduction.

In terms of individual level, I think we need to apply those same principles. We first need to recognize that there’s no way to completely eliminate risk, short of going and living in a cave somewhere. But then again, you introduce other risks, which are significant and valid. And then assessing your own risk tolerance. Are you a person who generally has higher or lower risk tolerance? So you start there. And then, if you’re thinking about something like travel, it would be assessing your risk factors. Do you have a preexisting condition like diabetes or heart disease? Or are you obese? Do you have preexisting lung issues? If you do, that sort of pushes you a little further into the more cautious. We think about it as a spectrum where on the left, you’re going to be not cautious at all, [and] on the right, you’re going to be more cautious.

If you have risk factors, that pushes you a little further over to the right, or if you live with someone who has risk factors, that pushes you a little further to the right. Think about the importance of the trip. Are you going to be with a relative, like someone in your family because there’s been a death in the family? Funerals aren’t really happening that much right now. But let’s say there’s a death or there’s a birth of a new baby. That’s a much more important, perhaps, event than something that is work-related and not essential or even a vacation.

You have to evaluate your tolerance of risk, as I said, and also your tolerance of inconvenience. Because especially if you’re going to be traveling by air right now in places where that’s possible, from everybody that I’ve talked to [who] has traveled by airplane recently, it has not been a pleasant experience. So there are a lot of precautions that need to be taken when traveling. And it’s already, air travel, with all the procedures, checkpoints, and stuff, was somewhat unpleasant, but it’s become even more that way. You need to think about whether you can practice good hygiene and social distancing, both en route while you’re traveling and wherever you’re going to end up. So I think those are all considerations for travel.

I generally think car trips are safer than flights at this point. And so we’ll probably be seeing a lot more road trips during the summer. In terms of getting together with groups, in some places they’ve relaxed the restrictions on [that], or relaxed the sheltering in place order. So, in theory, it’s possible to go out and have dinner with some friends at their house or vice versa. I would apply the same kind of framework that I just mentioned. Assessing your risk factors, evaluating the importance of the gathering, evaluating your tolerance of risk. Can you practice good hygiene and social distancing in those situations? Are you potentially going to be exposing other people that are at higher risk?

So, for example, I’d really love to see my parents. It’s been a while. I’d love for them to see their granddaughter and they’ve got other grandchildren that they haven’t seen, and they’re really missing them. But so far, other than some distanced outside visits that they’ve had with my brothers and their kids who live close by, there has been very limited in-person interaction because we’re really wanting to protect their health. And we know that people who are asymptomatic can be carriers. So that’s something, too, that is difficult and sad. I feel sad about it. But I feel more strongly about protecting their health and well-being until we learn more about this virus.

Will Welch:  Yeah, and I think you make a good point there about we’re not just making decisions for ourselves, we’re also making decisions for the people that we’re interacting with. And those can be the people that we care about the most who may have certain risk factors, like parents.

Chris Kresser:  Yes, yes, certainly.

Will Welch:  So we’ve talked about the million-dollar question. How about the five-million-dollar question? How do you see this pandemic ending?

How Might the Pandemic End?

Chris Kresser:  Yes, that’s the five-trillion-dollar question, perhaps, or even more. Now we’re thinking in trillions for sure in terms of economic impact. So yeah, there are a lot of ways to think about this. And I mean, let me just say, I’ll start by saying, I don’t know. And I think anyone who claims to know with certainty how this is going to play out is not being totally honest. And I’m, of course, not an epidemiologist or a virologist or an infectious disease expert. So my opinion is just based on following this very closely and being connected to many of those types of professionals and having lots of conversations with them and following all the research and news as everybody else is.

But my sense of this question, I mean, there are many variables [that] will affect the answer to this question, of course. So one of those is whether immunity is permanent to SARS coronavirus-2. If it is, then we can see it coming to a kind of distinct end where it really just, the number of new infections just gradually drops to almost zero and it’s effectively over. If immunity is not permanent, then it’s unlikely to end per se so much as it, that it might kind of gradually peter out or gradually lose significance and end up, or even persist at a significant level, but hopefully with smaller waves over time and maybe less severe impacts. So there’s a scenario in which immunity might not be complete such that people who have been infected before don’t get infected again. But it may be that the second time that they get infected, the effects are less severe.

So those are some scenarios that depend on what happens with immunity. And there’s been some interesting recent news about this. We still don’t really have the answer to that question. But there were brand new data that came out from South Korea just this morning that showed that people who tested positive for a second time, [who] they’re calling re-positives, are only shedding dead viral particles and they’re not actually infectious. So that’s good news, because that suggests that an immunity may be longer lasting and people aren’t getting it twice.

There were also some new data published this morning, as well. I mean, this is how fast things are moving. I do some preparation for the episode and then literally 12 hours later, I have to add or change things based on new data. So survivors of SARS[CoV]-1 from 2003 were found to retain neutralizing antibodies, nine to 17 years later. So it’s possible that functional antibodies to coronavirus can persist for a lot longer than previously shown. Because the idea has been that antibodies to SARS and MERS [Middle East respiratory syndrome] are shorter term than for many other viruses. So those are some positive new data that have come out recently in favor of the idea that we might develop immunity.

Another really important thing to understand is that it may be a misconception that we have to get to 60 percent infection rate in a population to see benefits. And that’s commonly the threshold that is thrown out there for reaching so-called herd immunity, which is the point at which the virus stops spreading through the population because enough people are infected already. And describing this is pretty technical. And we’ve already been going for a while. So I think I’m going to skip the hardcore technical explanation. But essentially, there are two numbers that are important to understand, and I think they’re widely misunderstood and have even been misused in a lot of articles.

  • One is R, which is the expected number of people that one infected person will pass the virus on to.
  • The other is R0, sometimes called R naught, which is the expected number of people that one infected person will pass the virus on to in a population where everyone is susceptible.

So the only difference between those two numbers is that R refers to how transmissible a virus is in a population where some people already are infected and not susceptible, whereas R naught or R0 is how many other people you will infect in a population where everyone is susceptible. So R0 is mostly impacted by things like social distancing and contact tracing isolation, because those are the most effective measures when everybody is susceptible—when the virus first hit the scene back in January and February. But R actually depends on two things, the R0 value and the percentage of the population who are not susceptible.

So, as you can probably gather, as the number of people in a given population goes up, then R will decline, even with no changes in social distancing, masks, etc. So somebody did an analysis using both R and R naught, and they found if just 13 percent of the population becomes infected, assuming an initial R naught value of two, R would drop to 1.75 with no changes in social distancing or masks or anything. At a 25 percent infection rate, R drops to 1.5. So that’s a half point drop from the initial R naught value just from more people getting infected. And then, if you combine that drop in R with a drop in R naught because of the social distancing measures and masks and things like that, then it’s conceivable that you could get to an R less than one where the number of infections starts to decline rather than stay stable or increase quite a bit before the percentage of the population being infected gets to 60 percent.

So, for example, if R naught can be dropped to 1.5 through social distancing, and masks and other measures, then you could potentially get to an R below one or where the infection stops spreading at a 40 percent infection rate rather than 60 percent infection rate. So this is still not, these are models, [and] models are not perfect, as we’ve learned. But I think that’s somewhat encouraging news that hasn’t been widely understood.

Will Welch:  Yeah, I think that’s helpful context that as more people get infected, things change. And as we do more behaviors, like wearing masks and staying home, things will also change. And scientists are out there collecting data to find out the impact of these different things. And as you’ve said, more and more is out there and being reported, and we have a better sense of what that impact actually is.

Chris Kresser:  Absolutely. And of course, in any discussion that we have about how this is going to end, we need to talk briefly about vaccines and antiviral medications. So there’s been some big news on the vaccine front this week.

One report from Moderna, which was just released yesterday, at the time of this recording showed positive phase one trial results in a very small sample size, eight people. Normally, data would never be announced for eight people. But these are the times we live in, right? And these eight people produced neutralizing antibodies to SARS coronavirus-2 that were similar to antibodies seen in the [patients with] COVID-19 [who] had already recovered. So that’s a very positive finding. Of course, this is only a phase one trial. There [are] lots more steps to go through. But it’s an encouraging result for sure.

On the other hand, we had results from the Oxford lab that suggested that their vaccine won’t fully protect against the disease, but just reduce its severity, which is similar to how the flu vaccine works. And the downside of that is that a vaccine that reduces symptoms rather than completely prevents infection takes a lot longer to develop than one that does prevent infection. And it also requires studying a lot more people. Because if 20 to 40 percent of infections are asymptomatic, assessing the reduction of disease severity as the primary endpoint rather than preventing infection requires much larger trials with more people and much longer study periods.

So that was kind of a bit of not so great news on the vaccine front. And then there are other significant challenges with vaccines. It’s not just a question of can we develop a vaccine and will it work and will it be safe? It’s also a question of can it be deployed at the scale that it needs to be deployed at in order to be effective and help get us to a herd immunity situation or to end this pandemic? And that depends on manufacturing capacity. And it’s not something that we can necessarily just throw money and resources at and get the outcome that we want because there is a shortage of certain supplies that are critical in the manufacture of some of these vaccines. And it seems almost silly in a way, but the glass vials that many vaccines are stored in require a certain type of sand that they’re made from that’s in short supply. And so that could be a bottleneck, pun intended.

Will Welch:  And we’ve seen it with the PPE, with masks, with ventilators.

Chris Kresser:  Of course.

Will Welch:  All these supply chain issues are really coming to …

Chris Kresser:  It’s so frustrating, right? Because you think, like, wait a second. We can’t just make more cotton swabs? Like, those are not, we’re not talking about high-tech gear here. Or a mask actually like an N95, it seems like when we just bought them in boxes before, they seemed pretty low-tech. But they’re actually quite difficult to manufacture and there are only a few companies that do it, and they can’t just ramp up capacity immediately. They have to build the equipment. So it’s the glass vials, the stoppers that you use to plug up the glass vials for certain vaccines. Certain materials are needed in those stoppers because they can, if you use the wrong material, it can interact adversely with the vaccine, and those are in short supply. Only a few companies make those. And so, again, these are sort of the not very sexy or glorious aspects of the process, but they might end up standing in the way of getting to the point where there’s not only a vaccine that’s effective, but there’s one that can be distributed widely.

And that’s the other challenge, or thing that’s worth pointing out, [is] just like with the flu vaccine, there’s probably not just going to be one vaccine. There’ll be multiple different vaccines, some of which might be more effective and safe for kids, and some of which are better for pregnant women, some of which are better for the elderly. And so we’re going to have, there’s probably going to be multiple vaccines, and then there’s going to have to be this effort to distribute them on a wide scale. So I have, I’m definitely not an expert in this area. But I think the idea that we would have, it’s at least possible that we could have an effective and safe vaccine in 12 months. But that would be if every single thing goes right in the process. But that’s different than saying, everybody listening to this show will have access to that vaccine in 12 months. I think that’s almost certainly not going to be the case. Because there’ll be a relatively long path from when the vaccine is ready to when billions of doses of it are available or even hundreds of millions for people in the [United States].

And then there’s, of course, just the question of safety that’s on everybody’s mind because previous vaccines for coronavirus have led to antibody-dependent enhancement, which actually can increase the severity of acquiring those coronaviruses. And that’s something that everyone’s going to be looking out for in the development of these vaccines. And I think, fortunately, in the Moderna case, and maybe also the Oxford case, there was no evidence of antibody-dependent enhancement. But these sample sizes are very small. So they need to have much larger sample sizes to be able to rule that out.

Will Welch:  Yeah. And you also talked about another strategy, which would be the antiviral drugs, as well. Did you want to touch on that?

Chris Kresser:  Yeah, again, it’s not my area of expertise, but I’ve been following it pretty closely in talking with our infectious disease doctor on staff, Dr. Asfour, who’s been on the show a couple of times. And certainly, there are some drugs like remdesivir that have emerged that seemed to lessen the severity of COVID[-19]. And I think that’s a promising route for development. I was listening to a podcast with Marc Lipsitch, who’s an infectious disease specialist, [who] works a lot on vaccines, and I’m sure many people have read or heard something from him during this pandemic. He’s been pretty vocal. He was saying that one of the most promising areas for therapy is coming up with drugs that can be taken very early, that will slow or stop the progression of COVID[-19] to the point where it gets very severe. Somebody first starts to feel symptoms, they take this antiviral medication, and that significantly reduces the likelihood that they develop pneumonia.

If we had medications like that, rather than just relying on medications that people take when they get to the hospital, and they’ve already progressed to a serious point, that would be a huge step, because it would really dramatically reduce the burden on the healthcare system and lessen the severity of infections. And I think, arguably, that would be an easier goal to obtain is developing drugs like that. Because if you look at most antivirals that exist today, they do tend to be much more effective when they’re taken early on in the progression of the disease, and they become a lot less effective the later they’re taken. So I think that’s a fruitful avenue for exploration.

Will Welch:  Yeah. I’m hearing from you that there are lots of potential points of intervention and that this is going to be a multifaceted strategy of all these pieces of the puzzle coming together to slow this down to a point where the economy opens up, [and] we can all start to get back to some of the things that we enjoy. But it’s not going to just be a silver bullet. It’s a lot of things here in the mix.

Chris Kresser:  Yeah, 100 percent. And I think it’s also important to understand that this is not going to be a linear progression. I think that’s another thing that the powers that be failed to communicate. There was this idea that we’d have an early spike and then it would just be all downhill from there. And I don’t think that’s going to be the case, at least in some places. It may be in certain areas, but it may not be. We’re probably going to see sporadic waves of outbreaks and spikes as we kind of resume more normal activity.

There may, unfortunately, even be additional times where we have to go back to shelter in place, at least in certain areas. Nobody knows how this will play out. But I think cultivating what we’ve talked about many times now, cultivating realistic optimism is the best approach where you pay attention to what some of the worst-case scenarios could be, or at least, not great scenarios. And you do your best to prepare for those so that you are prepared if they happen and you’re not caught totally off guard either practically or psychologically. While also making sure to spend an equal, at least an equal amount of time attending to opportunities and upsides and bright spots that come about from COVID-19 and our experience with this pandemic. So that’s definitely my approach and it’s the approach I continue to recommend for everybody.

Will Welch:  Thanks, Chris. I think realistic optimism is probably a good note to end on. Thank you for all the information, [and] for breaking things down. I think it’s really helpful. It’s been a helpful context for me. So I appreciate it and appreciate the opportunity to get to ask you all these questions.

Chris Kresser:  Well, Will, thank you so much. It was a pleasure to answer those questions. I think you did a phenomenal job and it was a great conversation, and I appreciate you being willing and game to jump in and do it on such late notice.

Will Welch:  Happy to. [I] appreciate it.

Chris Kresser:  Okay, everybody. [I] hope this was really helpful. Feel free to send it on to a friend or family member you think would benefit from it. I’m just really eager to get this information out to as many people as possible so that we can make our response to this.

Stay safe and healthy and sane, and really come together and support each other as we move through this. That’s my hope that over time, we can try to be a little more on the same team as we approach this because we really are all in this together. And I think that’s abundantly clear. We’re connected whether we want to be or not. So it’s a good idea for us to keep that in mind as we navigate this. Keep sending your questions in [to] ChrisKresser.com/podcastquestion and I look forward to talking to you soon.