Matthew Ferrari is an epidemiologist and associate professor of biology at Penn State who studies infectious diseases and how they spread across populations. He uses mathematical and statistical tools to understand patterns of disease incidence. He talked with WPSU's Cheraine Stanford about the new coronavirus, what we know, what we don’t and what it means for our community and our country.
TRANSCRIPT:
Cheraine Stanford
Welcome to Take Note on WPSU, I'm Cheraine Stanford. Matthew Ferrari is an epidemiologist and Associate Professor of Biology at Penn State who studies infectious diseases and how they spread across populations. He uses mathematical and statistical tools to understand patterns of disease incidence. Matt Ferrari, thank you so much for joining us today.
Matthew Ferrari
Thank you for the opportunity.
Cheraine Stanford
We've heard the coronavirus called the new or novel coronavirus. What other coronaviruses have there been or or why is this different?
Matthew Ferrari
Coronaviruses are a class of viruses that have been around and and are part of the things that make humans and other animals sick all over the place. And in some sense, the the ubiquity of those kinds of viruses is is part of the problem is that every so often a coronavirus will will find its way from an animal host into a human host, and that's rare because it has to have the special kinds of mechanisms to recognize a human cell and invade a human cell and then ultimately cause illness. So it's very rare but it does happen occasionally. The two most famous cases prior to this were SARS and MERS. So Severe Acute Respiratory Syndrome, which emerged in the early 2000s, and MERS, which has continued to, to reemerge from camels into humans periodically. So those are all classes of coronaviruses, and those were new at the time and new to science. We had never seen ones that looked exactly like that. And the progression of disease was a little bit different. So this is just another of these. It's a class of viruses that we refer to as zoonotic virus it comes from an animal into a human and it caused an unusual collection of symptoms. This combination of pneumonia and coughing and tiredness and things like that. And then the progression of that disease, which again, in many people is mild, but in proportion, maybe 20 percent or so, is much more severe than we think of, in terms of what the the the common coronaviruses that we're used to would do.
Cheraine Stanford
Is it mutating?
Matthew Ferrari
Yeah, this is a great question. And I hope you don't mind if I step into professor mode here for a little bit, right?
Cheraine Stanford
Go for it
Matthew Ferrari
So every single virus mutates constantly. And this is a really important thing to keep in mind. Right? So the fact, so the answer to the question of is the coronavirus mutating is of course, yes, every virus is all viruses are mutating. In fact, the virus that gets into me and the virus that leaves me and gets into somebody else, you know, it's not the same it's not the same virus particle is going to get into me proliferate massively, and the and whichever one gets out of me and gets into somebody else is going to look a little bit different because it's going to be continually mutating and continually changing, right. So that's something that happens all the time. The difference, and the important difference is whether that mutation is functional, whether it actually reflects a change in the behavior of that virus, and the way that it causes illness or the way it gets into people. Right. And so all the evidence we have at this point is that there has been no meaningful functional change in this virus from the time it's emerged to China, to the virus that's circulating the United States, we can track some small changes, and that actually allows us to figure out where it might have come from where the introductions may have come from. So we can see that it is doing what normal viruses do, right? But it doesn't appear to have changed in any functional way that would mean it's transmitting faster or slower or infecting people differently or causing disease in any new way.
Cheraine Stanford
Another thing that people are talking about a lot is this idea of flattening the curve. This is radio, but I think we've seen the curve that you know, there's a big spike in the middle and then it flattens out a little bit. And we're being told, you know, the social isolation, these other things will help flatten the curve. First, can you tell us what that normal pattern of disease is and how flattening the curve actually helps? What does it mean to flatten the curve?
Matthew Ferrari
So the best metaphor that I usually find for an epidemic is is like a campfire or a forest fire, right? So there are a lot of people out there that are susceptible to being infected, right, so they have no predisposing immunity. If the virus comes in contact with them, they will become infected and may likely experience disease. And if there's a lot of those people out there, and they're tightly packed together, it's like having a lot of a lot of firewood on a campfire or a dense dry forest. Right. And if you were If you were to set a match to that, it might flare up dramatically. And the bigger that forest and the more fuel there is, the faster that fire is going to burn, right? But a fire that burns really quick is going to spread through that forest rapidly and burn everything. Right? And it's going to burn really hot and really fast. Right? That's oftentimes that's really what we're talking about when an epidemic spreads. Now that fire is going to burn itself out because it's going to burn through the entire the entire forest, right. And that's what happens when it when an epidemic takes off. And then it will have gotten through the entire population gotten everybody sick and there's nobody left to get sick and the epidemic will will will tail off at the end. Right. Now, the issue is how hot of a fire can your system really support? In this case, a hot fire means lots and lots of people getting sick all at once. Right? And again, even though the majority of people will experience mild symptoms, or flu like symptoms that wouldn't require a significant medical intervention that can be managed at home, 20 percent of people that experience this infection require hospitalization. And if you can imagine if 20 percent of the world's population needed to be hospitalized in a short in short order, then we would rapidly run out of hospital beds, we would rapidly run out of ICUs, our doctors would be completely run ragged, right? And in that event, when there isn't enough health services for everybody that's ill, then the outcomes for each one of those people are that much worse. So that's the sort of doomsday scenario that we're talking about. And so the idea of flattening the curve means that we won't put quite the same demand on the health system.
Cheraine Stanford
So it still sounds like there's still going to be lots of people who are going to get it and maybe it's the same number of people. It's just that it would be spread out?
Matthew Ferrari
The simplest representation of flattening the curve would would mean exactly that, right. You get you get, give or take about the same number of people sick over a much longer time period. Right? And I'll be honest, that doesn't sound very good either. And especially given the, the the economic and psychological consequences of this outbreak, I don't think any of us of us want that thing, right. But what were the other thing that we're doing by by flattening the curve is buying ourselves time to come up with other kinds of interventions that might, might help us shorten the curve on the back end. And if we can do that, then that will get that might that still might not get rid of this virus 100 percent. But that will buy us even more time to develop the new drugs that lots of people are working on, that will be specifically targeted at this virus, right. And in order to develop those drugs, we need to do the basic science r&d, but also test them in in populations, ensure that they're safe and effective, assure sure that we know the the correct dosing regimens that don't have negative consequences, go through all the regulatory procedures and develop the industries that can scale them up, produce them in mass quantities and get them out to everybody in the world, right. And then if we can do that, then we'll have bought ourselves even more time for developing developing a new vaccine. Right. And that also is a thing that takes a long time to develop both in terms of r&d, but then also testing.
Cheraine Stanford
I know from the research, we're 12 to 18 months out from a potential vaccine.
Matthew Ferrari
That's right
Cheraine Stanford
So the term social distancing and restrictions, things like people working from home, only essential businesses being open. A lot of the least initial restrictions, there's a discussion about it being through mid-April or so, is that enough time to make a difference?
Matthew Ferrari
Yeah. Wow, that's a great question. And that's really two questions. So let's, let's, let's address it in parts. Right. So let's first talk about this thing called social distancing. Right? So again, right now, behavioral interventions are really the only tool we have at our disposal. And so that's why we're relying on them so heavily, right? We don't have the drugs yet. We don't have the vaccines yet. And so we're going to use the tools we have at our disposal to try and buy us time, right to put things in place so that we can use those and in fact, our existing medical infrastructure, I think, probably can handle this thing. Right. But we've got to give it enough time to get set up, right. Our doctors and our health systems were caught unawares when this thing took off, and we really need to give them the time to build the staffing, build the procedures, get everybody trained, right, and get ready to handle this thing as it increases, and so that's why we're so reliant and that's why it's so important for us to use these behavioral interventions. And again, I think it is worth notice- it is worth noting some of the the secondary consequences of, of social distancing. There are economic consequences, there are psychological consequences, right, everybody is, is dealing with this and we have to recognize that we're playing a cost benefit game here. And that it's important to use the time that we have that this is buying us to put in place those other procedures so we can relax it so we can start to return to normal operations and get everybody back working again and getting everybody seeing each other and interacting with each other again, and building our communities. Right. The term many of us are trying to sort of shift the terminology a little bit to talking about physical distancing, which is what we're actually doing, rather than social distancing, right. We actually want to maintain the social fabric of our communities and interact with each other online and, and use some of these other mechanisms to, to stay in touch with each other. Because in fact, what we're doing here is a community-based response.
Cheraine Stanford
Do we need to give it more time? I mean, you know, most people started putting these in place it, you know, two weeks or some places a month for some. Is that enough time?
Matthew Ferrari
Yeah. I wish I wish I had a good I wish I could tell you if it's enough time. I think the most important thing is for, for us to understand the limitations of, of how to assess whether it's enough time, right. So it's impossible for us to know at the outset, whether it will be enough time and what we need to do is we need to track the cases as they're increasing and see whether or not the the curve does start to flatten in the way that we're expecting, right. It's important to note that the cases that we're seeing now are people that were infected seven to 10 days ago, right? So the way this the way this virus works is you get exposed to the virus and then on average, five to six days later you start to experience symptoms. And the average person doesn't go and seek care on the first day they start feeling off. So it's a few more days before you start to realize 'I'm kind of feel a little kind of feeling a little weird. Maybe I should tell somebody,' right? So now you're talking about seven, eight, 10 days before someone that's infected is actually going out and seeking health care. And that's when we can count them. Right. So what we're seeing now is the result of infection that happened 10 days in the past, right? And what that what that means is that everything we're doing now in these behavioral interventions won't be apparent for another 10 or 14 days before we can really feel confident that the things that we're doing now are having an effect on flattening the curve. So, it's possible that everything we're doing now is is enough, right? And we're going to see things that are going to look great. But we're not going to know that for another two weeks into the future. It's possible that what we're doing right now isn't enough. And we'll see that cases have slowed but not slowed enough. Right. So, 10 to 14 days from now, we'll have some evidence that would suggest maybe we actually need to do things a little bit stronger. Right. So hopefully, what we're doing now is going to be effective. But we I think the really important thing is that everybody has to realize the the challenge of monitoring that and measuring that and evaluating that. And it's going to we're going to have to have some patience because it will take some time to to really feel confident that it's working.
Cheraine Stanford
If you're just joining us, this is Take Note on WPSU I'm Cheraine Stanford. Our guest is Matthew Ferrari an epidemiologist and Associate Professor of Biology at Penn State.
Cheraine Stanford
There have been some articles that I've seen about the fact that perhaps the coronavirus will will die down in warmer temperatures like in the summer. Do you know if there's evidence to that being true or not?
Matthew Ferrari
There hasn't been any convincing evidence that I've seen at this point. And again, there's, there's a couple of threads to keep in mind for that. One is that we've seen this thing broadly distributed across the whole globe, and it is increasing and growing everywhere. And while it might be cold here in Central Pennsylvania right now, you know, we're seeing this virus spread in places that are much warmer than us right now. So that's the first bit of evidence right. The second is that there might be an environmental link with this and it might over time once it's established, if it sticks, if it sticks around forever, might have a regular seasonal fluctuation, much like the common cold or flu, right. But right now, this virus is not limited by temperature. Right. So I think right now, it's this is just not the time where a minor change in environmental conditions or temperature conditions is going to have a very big effect, because the virus is largely responding to how much resource out there, how many people there are, that can be infected. And that's really what's driving things. We may see those seasonal patterns becoming important and relevant, you know, one to two years from now, if this virus stays around that long.
Cheraine Stanford
I think what most people really want to know is a question that I know you can't really answer, which is, how long will this last? So I'm not going to try to ask you to predict but do we have a sense of, are we weeks, months, years out from some sense of normalcy?
Matthew Ferrari
Yeah. Yeah, exactly. I mean, I keep I've been studying infectious diseases and outbreaks like this for for a long time and I really wish I could lean on that experience to give everybody the answer that they want. And I can't. And if anything, I can tell you that maybe don't trust me because I've always gotten it wrong in the past. Every prediction has missed the mark by some amount. But so there's a couple of things that we there's a couple of ways to look at this question. Right. So one is just to look empirically, where else has it gone up and come down? And and what was the timescale of that? Right? And how do we compare to that? So if we look at Wuhan in China, which is the the the city in Hubei province where this outbreak started, right, it took them 12 weeks about from the emergence of this virus to the flare up of the outbreak until they got it under control and to the to the first time they had five days in a row of zero cases. Right. So that's 12 weeks and that's under pretty draconian response. They really, you know, went and went into full lockdown. And people went into their apartments and stayed there for weeks or months at a time. And they encircled the town and didn't let anything come in and didn't let anybody go out. So under a, you know, under the most severe restrictions, China was able to end that outbreak in 12 weeks. I think that would be a very optimistic view for the United States right now. The distribution of this virus across the United States is much broader than it was in China. Eighty-five percent of all the cases in China occurred in Hubei province alone. And so the outbreak was maintained at relatively low levels throughout the rest of China. So I think that 12 week number is a lower bound and optimistic bound. I think it would be reasonable to think that we might see a peak of cases somewhere in the period between May and June, and then you know, it'll take a while for that peak to, to die off. Right. So I think that it's, I can't make a strong prediction, but I think it's reasonable to assume that we that this virus will be a part of our lives in a meaningful way throughout the summer and we should expect some level of disruption through that time period. If it goes away faster, then we'll all be happy and you guys can all you know, you guys can all happily hang out at the bar and talk about about, you know, how alarmist Ferrari was. And, and I'm going to, I'm going to welcome that if that's if that's the case, right. But I do think it's important for everybody to be considering the risks of things happening on that timescale for a couple of reasons, right. One is, if we trivialize what this thing might do, then we're not going to put in place the level of response that's necessary, right? So sometimes it's important to consider the worst-case scenario, because you need a call to arms to get everybody engaged and involved in ensuring that the worst-case scenario doesn't happen. And if things were to take that long, right, the things that we would need to put in place to ensure that we could that we could achieve that, many of those things, we have to start now. Procurement for hospitals, development of new drugs, development of clinical trials to evaluate existing drugs, right, those things all take time and if we wait to find out that the optimistic scenario didn't play out, then we're that much further behind the ball.
Cheraine Stanford
I think another set of questions that we got was really about how the disease is transmitted and if we are sure, fairly certain that we understand how it's being transmitted,
Matthew Ferrari
So, we're pretty sure how it's transmitted in the majority of cases, right. It's transmitted by respiratory droplets or by fomites. Right. So those are, you know, jargony words. Respiratory droplets are the spittle and sputum that comes out of your mouth and your nose when you're talking or coughing or sneezing or things like that. And we can all think about what happens when we get it when we start excitedly talking about something and, you know, little bits of little bits of saliva go flying out of our mouths and we don't think about that from day to day when it's happening, but it happens all the time. And that's one of the reasons that physical distancing is so important. Yeah, you might not you might go to the bar, and it might be loud and you're having a conversation, you're putting your heads together and talking closely and you never touch each other. Right? So you might think, Oh, yeah, we're not there's no way that we can transmit to each other. Right? But really, what you're doing is you're talking close and talking excitedly and those little respi-, you know, those little bits of droplets are flying around and might land on someone's nose or eyes or mouth, right. So that One of the ways, the other thing that happens is that those droplets end up on surfaces, right. That's, we call that fomite transmission. It ends up on that surface, you touch that surface with your hand, you touch your mouth with your hand or your nose or your eyes. And, and again, you know, that's not just am I having a conversation with somebody really close and transmitting to them that way, but were the people before me at the bar, having a really excited conversation and then I went, and I went up to the bar, and I ordered my drink and I put my hand down, and I and I, and I touched my mouth with it, right? So that's where we worry about high traffic surfaces, places like things like doorknobs and, and stair rails and things like that places where lots and lots of people are coming through. That's one of the reasons that we're doing things like telecommuting and shutting down offices and buildings, right, is because those are high traffic areas where lots and lots of people are coming through and even though you're not directly interacting with another person, right, you might be there in short order after they had just come through, right and and run the risk of touching a surface that they had, that they had contaminated.
Cheraine Stanford
What about packages and mail that's shipped to us? And then takeout containers?
Matthew Ferrari
Yeah, what the work has been done has shown is that basically, so yes, this thing can get onto a surface and stay viable, certainly for a period of hours and in idealized conditions, maybe even longer than that, possibly for days, right. But again, let's be clear, when I say that those are idealized laboratory settings, right. And the more porous the surface, the less long it can it can last, right. So so for example, on on, they found that it could last for maybe several days on a copper surface right. Now when you think about it, not many of us have copper surfaces around so we don't need to worry about that so much, right. But, you know copper and then stainless steel, maybe it can last a little bit longer and, and less on a wooden surface and less on a on a on a particulate surface or a paper surface or something like that. Right. So the more porous the surface, the shorter the duration that this thing can last. Right? So that's the first that's the first thing to keep in mind. And even on those surfaces, while the while it is still possible to recover infectious virus, there's a rapid degradation of the virus. So what does that mean for the things around us? We should definitely still be cautious about any surface, whether it's a door handle, you know, a stair railing, or packaging for something, right, that interacts with lots of other people. Right? That doesn't mean we need to completely avoid those things and we still have to go shopping and we still have to get to places we get to right. What it does mean though is that when you've interacted with any kind of surface or any kind of, you know, physical product that other people might might likely have interacted with recently, right, then you should just be thoughtful and try and wash your hands as soon as possible and avoid touching your face to complete that cycle of transmission, right, just getting from the surface onto your hands is no particular risk. It's getting from the surface to your hands, to your mouth, or to your nose or to your eyes and that's that that's the behavioral interaction that we want to break up.
Cheraine Stanford
Can we stop viruses like this in the future or are they sort of inevitable?
Matthew Ferrari
They're sort of inevitable. There's no way to stop these things from ever emerging. There are ways to prevent them from spreading broadly and there are ways to build robust health systems that can react to them very quickly. So, you know, yeah, you can't, you can't predict the, you know, these, these rare occurrences and evolution and natural selection are way more creative than than we are. Right. But again, we can build robust systems that can react to them really quickly. And I again, I think we have a really, it's really important that we learn from the experience of this outbreak to ensure that the structural inequities, the structural vulnerabilities in the U.S. system in the U.S. health system, in access to care in the in the ability of our manufacturing systems to rapidly pivot and produce necessary products. You know, those are vulnerabilities that we're all just learning about because things were pretty good for a while and we didn't need them. We didn't need to worry about them. And I think now it's really important that going forward, right, we account for this and build that kind of robustness and redundancy into our systems so that we won't be caught off guard again, in the future.
Cheraine Stanford
What is something you want to make sure that people hear if nothing else from this interview, kind of loud and clear about either this virus or what it's taught us, whatever it is, what is something you want to make sure that our audience understands?
Matthew Ferrari
I think the most important thing is that right now, this is a community-based response and the only way that we overcome this is to work together as a community to do so. So, no matter where you are on the various spectrums, there are people that are worried about this mostly as a health issue and people that are worried about this mostly as an economic issue, right. The solution to all of that is to try and come together and end this thing as quickly and efficiently as possible. And that requires that we all come together and work together to provide a community solution to this. And I think again, it's a really powerful time for us to to reflect on the role of our behavior individually in providing a safe and healthy community for everyone else around us.
Cheraine Stanford
Matt Ferrari, thank you so much for talking with us.
Matthew Ferrari
You got it.
Cheraine Stanford
Matthew Ferrari is an epidemiologist and Associate Professor of Biology at Penn State who studies infectious diseases and how they spread across populations. Hear more Take Note interviews on our website at wpsu.org/takenote, I'm Cheraine Stanford WPSU.
