Denial And Lies Are 'Almost An Intrinsic Part Of An Epidemic,' Doctor Says

DAVE DAVIES, HOST:

This is FRESH AIR. I'm Dave Davies in today for Terry Gross. Our guest, Nicholas Christakis, says the virus that causes COVID-19 will circulate among us in some form forever. Christakis is both a medical doctor and a sociologist and in a unique position to understand the science behind the coronavirus and place the current pandemic in the context of past attacks of deadly pathogens.

Plagues, he writes, reshape our familiar social order, require us to disperse and live apart, wreck economies, embolden liars and replace trust with fear and suspicion. He says they also elicit kindness, cooperation, sacrifice and ingenuity. In a new book, Christakis surveys the course of COVID-19, chronicles some tragic mistakes made by our political leaders, assesses how the pandemic may end, and considers some of its long-term impacts. Among his observations, if a vaccine arrives after two or three waves of the pandemic, it may be too late to make much of a difference.

Nicholas Christakis directs the Human Nature Lab at Yale University, where he is the sterling professor of social and natural science. His latest book is "Apollo's Arrow: The Profound And Enduring Impact Of Coronavirus On The Way We Live." He joins us from his home in Norwich, Vt. Nicholas Christakis, welcome to FRESH AIR.

NICHOLAS CHRISTAKIS: Thank you, Dave. Thank you so much for having me.

DAVIES: You're a medical doctor and a sociologist. And you direct the Human Nature Lab. What is that? What do you do?

(LAUGHTER)

CHRISTAKIS: Well, I am a doctor. I don't see patients anymore for many years. I haven't seen patients for about 10 years. But I was a practicing physician in hospice medicine. I took care of people who were dying. But my primary identity is as a research scientist and as a professor. I teach students. And the Human Nature Lab is my group at Yale. And the part of human nature we're interested in is that part that relates to how we interact with each other.

So we address questions such as the origins and functions of friendship in our society. Why do human beings form social networks? We look at ways that groups function. We look at how the introduction of artificial intelligence into our midst will reshape how we treat each other. We look at the flow of germs through social networks or the microbiome. We have a research initiative that looks at how people interacting allows them to share microbes in ways that reshapes their health, for example.

All of these phenomena, all of these things that move between us are affected by how we interact with each other and, in turn, affect how we treat each other. So the spread of ideas, the spread of money, the spread of germs, the spread of behaviors - all of those things depend on our interactions and, in turn, shape our interactions. It's this sort of network perspective, this sort of recognition that the whole is greater than the sum of its parts and that how the whole is assembled affects the experience of the parts. And an epidemic, to understand it optimally, requires a kind of bird's-eye view of the whole human network. And that's, I think, one of the things that network science brings to bear in understanding epidemic disease that's special.

DAVIES: You know, you're right that there are pharmaceutical interventions against plagues and pestilences over the years, typically less effective than nonpharmaceutical interventions - things like masks and social distancing. A lot of people were late in endorsing social distancing and masks. I mean, you noted that the World Health Organization was discouraging people from wearing masks as late as April 6th of this year.

You know, Dr. Fauci said in an interview on February 29 people, you know, didn't need to refrain from going to movies or malls at that point. My sense is reading your book, that you were watching this spread with some alarm because you're looking - you do a lot of research with social networks. Why didn't public health professionals act more aggressively sooner, do you think?

CHRISTAKIS: Well, amongst my colleagues, everyone was greatly alarmed in February. Now, why our political leaders didn't respond, I don't know. And it's the case that many political leaders around the world failed to take this seriously.

One of the arguments that I like to make about epidemics is that it's almost in the nature of epidemics that denial and lies about the - about what's happening is itself almost an intrinsic part of an epidemic, that in other words, everywhere you see the spread of germs for the last few thousand years, you see right behind it the spread of lies. And partly, that's because the person on the street wants to deny what's happening. And partly, it's because our political leaders don't want to take it seriously either. But it's their job to do so.

DAVIES: In the book, you cite a statistic. You say that if 70% of the public had begun wearing masks early on, it could prevent a large-scale outbreak of this pathogen. True? I mean, if we'd gotten on this and gotten really behind it early?

CHRISTAKIS: Yeah. So I think what's important to understand about this pathogen or about epidemics in general is that no single intervention is typically enough to stop an epidemic. And what I - the way I like to think about this and the way many epidemiologists think about this is something known as the Swiss cheese model. So imagine you have pieces of Swiss cheese that you're stacking up, and each of them has some holes in it. And they're random pieces of Swiss cheese, like you're making a sandwich and you're piling up pieces of Swiss cheese.

If each piece of Swiss cheese represents a defense, a layer of defense - for example, one piece is wearing masks, and another piece is closing schools, and another piece is banning gatherings, and another piece is washing your hands, and another piece is, you know, restricting travel or something. If each of those pieces represents some intervention and each of the holes is sort of randomly positioned in each slice, by the time you stacked up two or three or four slices, none of the holes overlap. And so a virus can't get through. It can't penetrate all the layers of defenses. So if you just use masks, you stop a lot of viral transmission, but you don't completely stop the epidemic. You also need to do something else.

And incidentally, this is why there was a super-spreader event at the White House. They relied on just one line of defense, which was testing. Testing was not enough. You need to do testing, let's say, plus masking or testing plus masking plus physical distancing. And this Swiss cheese model also helps us understand why different countries have succeeded in combating the virus using different mixes of interventions. You don't all need to use the same intervention. You can - each country or each region can use a different mix of interventions and still have success.

So, for example, in New Zealand, you know, they had border closures plus testing and quarantining. And in Greece, they had school closures and mask wearing and contact tracing and so on. So this is why masks are helpful, but they're not enough and also why we can understand a great variety of other ways in which our response to the virus among us can and should be optimized.

DAVIES: I've got to ask this question directly. I mean, we're in a political season where, you know, management of the coronavirus is clearly an issue. I mean, by - you know, by March, April, it was very clear that we had a very serious problem. And, you know, consistent national policy would be helpful. How do you rate the administration in its handling since then from - you know, from when that was clear up to now?

CHRISTAKIS: Oh, I mean, I think we clearly needed a national response. I mean, you know, having a patchwork of responses is like designating one part of the swimming pool as suitable for urination, but not the other parts. I mean, we are a whole nation that's bound together. And so we clearly need, in my view, a national response.

In fact, in some ways, you could argue we need an international response. But certainly from our own parochial point of view, we needed a national response. And even though it's the case that many other leaders in European countries made similar mistakes to our leadership, I don't think that lets our leaders off the hook. We're the United States of America. I expect more from us. We have the CDC. We spend 17.7% of our GDP on health care, and this is our level of preparedness? I mean, this is how our great nation is brought this low by this pathogen? You know, I think it's awful, frankly. It's incompetent. And it was, in many ways, unnecessary. We could've done and we should've done, in my view, much better. Why - when the Chinese shut down their country on January 24, why we weren't preparing to manufacture PPE and ventilators is mind-boggling to me. It was as if we were trying to wish the pathogen away.

DAVIES: All right. Let me take a break here. I'm going to reintroduce you. We're speaking with Nicholas Christakis. He is a medical doctor and a sociologist at Yale University. His new book is "Apollo's Arrow: The Profound And Enduring Impact Of Coronavirus On The Way We Live." We'll talk more in just a moment. This is FRESH AIR.

(SOUNDBITE OF MUSIC)

DAVIES: This is FRESH AIR, and we're speaking with Nicholas Christakis. He is a medical doctor and a sociologist at Yale University. His new book about the coronavirus is called "Apollo's Arrow."

The president's adviser, Scott Atlas, has been associated with the idea that the U.S. could achieve herd immunity, you know, without a vaccine, that letting it spread may be the best and safest and quickest course to getting back to normal. Is this a workable idea?

CHRISTAKIS: It's an idea. There is such a thing as herd immunity. Herd immunity is when a large-enough fraction of a population have acquired immunity to the condition, either naturally because they got infected or by vaccination, such that when that large-enough fraction is infected, even unimmunized people get protection. And the gist of the idea is that, look, if the virus has a certain level of contagion and if half the people are immune to it, even if someone by dumb luck were to somehow get infected, they couldn't find anyone to spread it to because many of the people around them would be immune. And as a result, the epidemic would peter out.

And herd immunity is the natural end to epidemics. You know, prior to the invention of vaccines, this is what typically would happen. The virus would spread and spread until some certain fraction of people were infected and - which varied by different germs, have different levels that are required for herd immunity. And once that was reached, then the virus became what is known as endemic. It was still there, but it wasn't - didn't have the same power to cause, you know, a lot of death in an epidemic fashion. So that's what herd immunity is. And so the question is, is that a rational strategy to shoot for? And I don't think the answer to that is yes. I think we can do better than that.

We have better means to prevent death among ourselves now, whether using nonpharmaceutical interventions to slow the spread of the pathogen and give us time to invent and deploy methods to preserve our lives or most importantly, to invent a vaccine because that is a safe exit from the current crisis. The reason we're flattening the curve right now, the reason we're engaging in masking and physical distancing and all the other stuff is to buy time so that we can invent a vaccine. And therefore, we can have herd immunity through vaccination, not through, you know, natural acquisition of infection and immunity.

DAVIES: I was interested to read in your book that in other cases where we've developed vaccines for infectious diseases like tuberculosis and measles and - that often by the time the vaccine arrives, the infection rates have already naturally lowered dramatically. What does that tell us?

CHRISTAKIS: Well, that's a general principle in public health, which is sort of in the background of all of the conversation. That's called the McKeown hypothesis, which was a very powerful idea from about 50-or-more years ago where Thomas McKeown the medical historian observed that if you plotted on the X axis time and on the Y axis, the number of people dying from any given infectious disease - tuberculosis or measles or diphtheria or whatever - and then you plotted the deaths, you have this sort of steep New England sled run of a graph, you know, where the mortality is high and then sort of drops precipitously. And then, there's, like, a long straightaway, you know, when you get to the bottom of the hill and the sled is just sort of coasting along.

And what he did is he generated these graphs for all these conditions, and then he put an arrow on the time point at which the specific treatment had been invented to treat that condition. So in the case of tuberculosis, it was isoniazid. In the case of diphtheria, it was, you know, antitoxin. In the case of measles, it was a vaccine and so on. And what he found was that, ironically, that moment when the specific treatment was invented typically was on the flat straightaway of the sled run long after mortality had disappeared or had declined substantially.

And his argument - correct. His correct argument was that really what causes the disappearance of infectious diseases is rising wealth and living standards and community and public health interventions. So the principle there is that what really matters in the control of infectious disease is not so much the pharmaceutical interventions, but the kind of way of living that we have. And that same principle in a smaller scale also applies with respect to the epidemic disease that we're currently facing.

DAVIES: Yeah, so let's play this out. You know, we're being told that a vaccine, you know, is being developed at warp speed. And maybe, that comes in a month or maybe six months or maybe a year. Are you saying that it may not affect the infection rate that much?

CHRISTAKIS: No, I'm not saying that because this is a bit of a different situation with an epidemic disease and the kind of acute, like, you know, novelty of the pathogen that's just striking us right now. And we're all vulnerable to it. I do think the vaccine is going to be very important. And if it arrives in time, I think it could play a role. Honestly, I'm a little pessimistic, however, that it will arrive in time to make a difference. And so we talked a moment ago about herd immunity. One of the things that's going to - you know, while we're trying to develop a vaccine, the germ is - the virus is still spreading among us. Only about 10 or 11% of Americans are infected. Probably about 45 or 50% of Americans need to be infected before we reach herd immunity. And the virus is going to come back in waves over the next year or two. And more and more Americans are going to get infected. And eventually, we're going to reach that critical threshold probably sometime in 2022.

So that's going to happen. You know, that is happening in the background unless we want to be so extreme that everyone lived as a hermit. In other words, if we all just stopped interacting with anybody, we could stop the spread of the virus. But, you know, that's not going to happen either. So - or we could invent a vaccine, which, I think, we're likely to have a vaccine of unclear safety and efficacy - probably more than one vaccine - sometime in 2021. But, you see, that's just the first step. Then we have to manufacture the vaccine in large numbers of doses, distribute it, which won't be easy.

There's something known as the cold chain. Basically, the vaccine needs to be refrigerated from the time of manufacture to the time of injection, which is not easy and, most importantly, accepted - that is to say, most Americans have to be willing to take the vaccine. And that's going to take a year or something. So either way, we get to 2022, in my view. So my feeling is that, unfortunately, during what I consider to be the immediate impact period until 2022, we're going to be living in this changed world where we're wearing masks and doing physical distancing. And, you know, our economy is so adversely affected, unfortunately.

DAVIES: That's really a bummer to hear (laughter).

CHRISTAKIS: It is a bummer. But, see, this is the thing. You know, plagues are also a time of grief. You know, we're grieving not just the loss of people we know, you know, who died or our health, we're grieving our loss of a way of life. We're grieving the fact that we can't have dinner parties with our friends. We can't go to movie theaters. I mean, this - just like we were earlier discussing how plagues are a time of lies, they're also a time of fear and they're a time of grief. And I think, in some ways, as a nation, we just need to - I won't say grow up. That sounds too flippant. I mean, we need to accept this unpleasant reality.

And this is, again, where I think leadership is so important. I mean, one of the things that's crucial is public health messaging credibility, you know, people who get up and tell it to us even if it's uncertain. Say, I'm not sure of exactly what's happening. But I think this is most likely and here's the data, because we need to prepare the nation, in my view, for this reality. I mean, what makes us think that we're so different, you know, that we Americans in the 21st century, in our wealthy country, will be spared this fate? There's no reason we should be spared. And I think that preparing the nation to come to grips with this unfortunate reality is crucial.

And, you know, we will see the other side of it. I mean, one of the things that's also important to recognize is that plagues do end. They have always ended. Even the bubonic plague ended. It's rare that there are so severe that the society is entirely annihilated. Although, that has happened, too. But that's not the situation we're facing. So there is also grounds for optimism in ways we can talk about.

DAVIES: So at some point, you know, several years from now, what will our relationship be with this particular coronavirus? You say it will be among us forever.

CHRISTAKIS: Yes. I think a very likely outcome is that this virus will become like some of the other cold viruses, the other four variants of coronavirus that just cause the common cold. You know, I think over at least - certainly over a century time interval, that's what's likely to happen. And what's likely to happen, I think, is that we will - remember that in this particular virus, if you get it when you're young, it's relatively benign. And then I think you will have some kind of lifelong protection or long-term protection. It's unclear how substantial that protection will be.

But what I think is likely to happen is that people will be exposed to this pathogen when they're young, will have a mild illness, they'll get some kind of protection. And then if they're re-exposed later on as adults, they'll get a mild illness again. As opposed to what's happening now when adults - all the adults on the planet have no immunity. And when they get it, you know, they're likely - they have a chance of dying. In a way, I think, it'll be like chickenpox. You know, you get chickenpox as a kid, it's unpleasant. But you don't die from it. If you've never had chickenpox and you get it as an adult, you could die from it. So I think it's going to be sort of like that is, I think, the ultimate outcome of this pathogen.

But in the intermediate period, I think we're going to have to come to terms with it. I think it will settle down. I think we will reach, as I said, either herd immunity or from vaccination or more naturally. And, you know, it's going to become a fact of our lives. But we're not going to be living as we are now forever. I mean, I think what's going to happen is that the immediate pandemic period will last until 2022, approximately. And then we're going to - will have recovered from the biological and epidemiological shock.

But then, if history is a guide, we'll have a couple of years of recovering from the psychological, social and economic shock. And, you know, the economy is not going to bounce back immediately. People aren't suddenly going to go back to airports or restaurants. So I think we're going to have this sort of intermediate period of a couple of years until, let's say, 2024. And then, beginning in 2024, I think we're going to have a kind of post-pandemic period.

DAVIES: Let me reintroduce you again. We're going to take a break here. Nicholas Christakis is a medical doctor and a sociologist at Yale University. His new book is "Apollo's Arrow: The Profound And Enduring Impact Of Coronavirus On The Way We Live." He'll be back to talk more after this short break. I'm Dave Davies. And this is FRESH AIR.

(SOUNDBITE OF CHICK COREA'S "SONG FOR SALLY")

DAVIES: This is FRESH AIR. I'm Dave Davies in today for Terry Gross. We're speaking with Nicholas Christakis, a sociologist and medical doctor from Yale University whose new book examines the course and impact of the COVID-19 pandemic and some of the mistakes made by political leaders and managing it. It's called "Apollo's Arrow: The Profound And Enduring Impact Of Coronavirus On The Way We Live."

If it's likely that we will be with this until 2022, when at some point we'll have a vaccine, but in the meantime, there will, you know, more people will be infected, which will give us something closer to herd immunity. What about the argument that it would be smarter to simply embrace the virus, accept mass and quick infection and get there sooner?

CHRISTAKIS: Well, let me explain why that's not a good idea in a very direct way. So if you had gotten this pathogen back in March, you would have had a higher chance of dying from it than if you get it today. Why is that? Well, because in the last nine months, we've learned how to take care of you. And in fact, we have discovered that a drug called dexamethasone, which is a simple steroid - which incidentally, the president also got - if given to you, if you're seriously ill, can prevent you can reduce your risk of death by 20%. In other words, if you got seriously ill from coronavirus in March, you would have a certain chance of dying. Let's say 25% chance of dying. But if you get it now, you might have, let's say, only a 20% chance of dying. That's a - seriously ill. That is to say now you would only have a 20% chance of dying. That is a big difference, and that's why we flatten the curve. So that's why not to go for the rapid herd immunity strategy right now.

That's one illustration of the reason is that by getting - by postponing the illnesses until a later point in time, we allow our scientists and our health care system to function better. If you get sick from this condition like that's happening now, for example, in Utah and in Idaho and in parts of Texas and in Oklahoma that are - where many of their hospitals in many cities are being overrun, when would you rather go to a hospital, when it's packed to the gills and the doctors are exhausted and the nurses are sick from the condition, or would you rather go when the hospitals are operating normally? Obviously, the latter. So this is why not to let the virus just run loose in our society.

DAVIES: What will be some of the lasting emotional impacts of the virus and the social isolation we've endured?

CHRISTAKIS: I think, first of all, in the long term, you know, in five or 10 years, I think society will have returned largely to normal, although there will be some enduring impacts which - of a variety of fronts, including things like working from home or certain economic impacts, which we can discuss. On the more shorter term sort of emotional things that you were alluding to, One of the things that's very typical - and we're seeing evidence for that in the United States - is during a time of a serious epidemic, religiosity rises. People become more religious. And that actually generally is reversed when the epidemic goes away. You know the saying - there are no atheists in foxholes. Well, we're under a barrage right now. So, you know, people get religious.

But then afterwards, you know, the religiosity sort of returns to baseline. I think there's other habits that are happening right now that are a little unclear how long they will last. But I think there's a lot more independence that's being cultivated. I mean, there's more home cooking and home plumbing repairs and home medical care. And, you know, people are expected to be more independent when, you know, social interactions and the economy, you know, are reduced and the economy slows down. And I think there is, however, a lot of potential harm that's happening to our children from the school closures, from the fear of what's happening, from the job losses that, you know, let's not forget, tens of millions of Americans have lost their jobs from this.

I think we're going to have a serious recession that lasts for quite some time as a result. And I think young and other vulnerable members of our society will be preferentially affected. And many young people will carry these marks for a very long time. So there are a host of different kinds of impacts - social, psychological, economic, clinical - on different people - young, old, middle-aged - of different backgrounds - Black, white, different races - different levels of wealth. It's a serious thing that's happening to us, and it is going to have multiple impacts.

DAVIES: You know, you've written that at times of plagues, people look for scapegoats. They sometimes turn on one another. On the other hand, it's a time when people need to come together to battle what's going on. What are you seeing here? Are we becoming more charitable, more empathetic or the opposite?

CHRISTAKIS: I think both of those are true. I think there is - on the one hand, you would, you know, there's this - when there's a serious threat afoot, you can have a kind of temptation to have sort of every man for himself. But it's also in the nature of contagious diseases that we need - that we're sharing a common enemy, so the impetus to band together to confront the common enemy is heightened. And it's in the nature of this enemy that collaborative work is necessary.

You know, if there was an invading army on our frontier, each individual citizen can't do anything about that. I mean, you can, you know, grab your gun and go to the frontier, but you can't stop the invading army. And even if every citizen independently grabbed their gun and went to the frontier, that's not very effective either. You need coordination. You need leadership. You need a way of working together to repel the invader. And that's the kind of invader that we have. That's the kind of adversary we have in this virus. We must and we are - slowly but, you know - working together to confront the virus. And this working together includes things like collectively implementing the non-pharmaceutical interventions. It's almost an oxymoron. You know, we have to work together to live apart.

But it also includes, you know, all this scientific and medical and other advances and public health advances that we're making. You know, we are working together as a species to develop knowledge that we can then use to fight the virus. So I, you know, I'm optimistic in this regard. Like I said, you know, we're going to see the other side of this. I think Americans are going to see that they - that collaborative effort is required. I think as deaths mount in the coming winter, I think the motivation to do this will rise. And, you know, I have hope and expectation that we will do a better job than we have in fighting the virus.

DAVIES: Let me reintroduce you again. We are speaking with Nicholas Christakis. He is a medical doctor and sociologist at Yale University. His new book is "Apollo's Arrow: The Profound And Enduring Impact Of Coronavirus On The Way We Live." We'll continue our conversation in just a moment. This is FRESH AIR.

(SOUNDBITE OF MUSIC)

DAVIES: This is FRESH AIR. And we're speaking with Nicholas Christakis. He's a sociologist and medical doctor from Yale University whose new book examines the cause and impact of the COVID-19 pandemic. It's called "Apollo's Arrow: The Profound And Enduring Impact Of Coronavirus On The Way We Live."

What are some of the most informative insights that we have from the 1918 influenza pandemic, the so-called Spanish flu, you know, both in terms of science and social behavior?

CHRISTAKIS: Well, it is the last major respiratory pandemic that we've had in the last hundred years or so that was, you know, severe. I think this - the 2019 coronavirus epidemic is probably going to be the second-worst respiratory pandemic we've had, so almost as bad as 1918 but not as bad. And so it is important to look back and see what happened to the people then and how did they respond but at the same time, to recognize that was a different era. That was before antibiotics. It was before modern telecommunications. It was, you know, it was - the economy was much more rural. People lived already in a more spread-out way. There was less urbanization.

So many things were different. But there are other things we can learn that are actually quite informative. We can see the time period that it took for people to bounce back between the 1918 pandemic, let's say, and the roaring '20s. Or we can look at the impact of school closures. And a very nice study was done looking at and showing that the sooner that a city closed its schools, the lower the impact of the pandemic in that city. It's very difficult to discover those things by doing experiments. You couldn't organize a national experiment right now where you closed schools in some areas but not in others. So we have to rely on natural experiments that were done, you know, in this case, a hundred years ago and look at the data and see what can we learn.

So there are quite a number of things we can learn. Masking is another thing. We - very ironically, there were the same fights about masking, if you can believe it, a hundred years ago. In some ways, that's really depressing to me how little we've progressed as a nation that we're still having these arguments. You know, masking is clearly helpful. There were anti-masking leagues, you know, a hundred years ago, people protesting the same thing, using almost the same arguments. So - but there were studies - scientists published studies showing that wearing masks reduces droplets. You know, a hundred years ago we had this work done.

DAVIES: But a lot of discussion about science and the extent to which people listen to scientists and value science. When this is over, will we value science more?

CHRISTAKIS: I would hope so. I mean, I think there's a very interesting sense in which, for a variety of reasons, I think our society has a kind of thinned-out intellectual discourse. You know, I think we have - we sort of see expertise as a kind of elitism. You know, experts are somehow seen as elites rather than as knowledgeable individuals and therefore are to be, you know, to be treated with suspicion. We have politicized and polarized to an extraordinary extent. We've lost the capacity for nuance in our conversations. You know, things are black and white. You're either with me or against me. You know, either you do this or you do the opposite. We don't sort of compromise or see things as having shades of gray.

And all of these features - the loss of nuance, the polarization, the distrust in science, the denigration of expertise - you know, have made us extra vulnerable to the impact of this virus. You know, this virus has struck us when we're weak in this regard. So I would hope that in a way we would learn our lesson. And there are some ways in which, if we see that science is a very powerful tool at our disposal to understand what's happening to us and to develop countermeasures, that this might, you know, lead to a kind of a more sensible perspective amongst the average American towards the utility of science. And we can argue about what policies to implement. We can have our ideological differences. But in an ideal world, we would let the scientists do their job.

DAVIES: Right. Getting past the election probably will help, right?

CHRISTAKIS: Yes, I think so. I think everyone would rather argue. In other words, what I don't understand about our current public discourse is why we would put our heads in the sand. For example, take climate change. There's so much fight - or gun deaths, you know, gun epidemiology or the biology of gender, for example. So both the left and the right, both the far-left in the far-right have their, you know, have their preferred topics which they would rather not have science shed light on.

What I don't understand is why we can't assemble the facts as best we can in using the scientific process and then have our ideological dispute about what to do about those facts. Why one or another side would wish to suppress the facts so as to avoid the ideological dispute, that's what gets us into trouble, in my view. So, for example, the argument about masks. Let's do the experiment. Either the masks help or they don't help. Let's let the scientists do their job. And then we can decide, OK, even if masks are shown to be effective, we're not going to use them because of our ideological commitment. Or even if the masks are ineffective, we are going to use them for whatever other reason. But let's get the science straight first, and then we can have our ideological dispute. Let's not cloud the waters is my concern.

DAVIES: Your most recent book before this was called "Blueprint: The Evolutionary Origins Of A Good Society." I haven't read it, but my understanding is it offers an optimistic view of our, I guess, biological capacity to live together in empathetic and supportive ways.

CHRISTAKIS: That's right.

DAVIES: It's a little hard to be optimistic these days when you see all this bitter partisanship in the country. And now we have this dreadful pandemic. What did your research tell you that should give us hope?

CHRISTAKIS: I think we're a remarkable species, honestly. I mean, thank you for giving me the chance to say this. You know, I am an optimist. And I see the good in people. And I like to see the good in people. And it's not - but I'm naive. I'm aware that many people are awful. And I'm aware of all the horrors, the inquisitions and the pogroms and the enslavement of others and the poverty. And I'm well aware of the horrors that human beings can inflict on each other.

But at the same time, we have so many wonderful qualities we humans do that are very rare in the animal kingdom. These include the capacity for love, the capacity for friendship, the fact that we cooperate with each other, that we make sacrifices to even benefit strangers, that we teach and learn from each other. These things that many listeners are probably taking for granted are actually very rare in the animal kingdom. And yet, we do them naturally. We evolved to do them. And I think this is miraculous (laughter). You know, I think that these wonderful qualities that bind us together, you know, that are - that reflect our common humanity are unbelievably unbelievable and wonderful to see. And so this is one of the reasons I'm optimistic.

Let me say something about this that connects the points. One is that you can even - there's even a sense in which the spread of germs is the price we pay for the spread of ideas. What do I mean by that? One of the reasons we have evolved to live socially is to learn from each other. Any animal can learn on its own. A little fish in the sea can learn that if it swims up to the light, it'll find food there. But we don't just learn independently like that. We learn socially. You put your hand in the fire, you learn that it burns. So you - that's independent learning. Or I can watch you put your hand in the fire. And I get almost as much learning and I pay none of the cost, which is incredibly efficient, that capacity for social learning. So we evolved to live socially, in part, to get the benefits of the spread of ideas.

But the irony is that the germs exploit those same qualities. The fact that we live socially, the fact that we make social networks - these are the highways across which the germs travel. That's why I said the spread of germs is the price we pay for the spread of ideas. But the irony is that the opposite is also true - that it's through the spread of ideas that we're going to beat back the germ. It's precisely because we can work together. We can cooperate. We can exchange information. These are the tools we're going to use, ultimately, in my view, to have victory over this virus.

DAVIES: A hopeful note. Well, Nicholas Christakis, thank you so much for speaking with us.

CHRISTAKIS: Thank you so much for having me, Dave.

DAVIES: Nicholas Christakis is a medical doctor and a sociologist at Yale University. His new book is "Apollo's Arrow: The Profound And Enduring Impact Of Coronavirus On The Way We Live."

(SOUNDBITE OF MUSIC)

DAVIES: Coming up, Maureen Corrigan reviews Jess Walter's new historical novel about the Wobblies and a landmark free speech protest at the turn of the last century. This is FRESH AIR.

(SOUNDBITE OF ROBBEN FORD AND BILL EVANS' "PIXIES") Transcript provided by NPR, Copyright NPR.