Jordan: I woke up one morning last week and I stepped outside and it felt like fall. You know the feeling I mean, it was warm, but no longer hot. Sunny, but crisp. It smelled fresh. And in any other year it would have made me smile because fall is my favourite season. In 2020, of course. It filled me with dread. Fall means the end of summer. And this summer might be the only break Canada gets from COVID-19 until we have a vaccine. It’s to think about what fallen winter will bring when it’s gorgeous out, and I can see my friends and my backyard and the patios are open. But we have to think about it. Or we won’t be ready when it hits. And in fact, depending on who you ask, we may have already blown a big chance to prepare for this winter. So, don’t shoot the messenger? But look, winter is coming. What are we going to do about it? I’m Jordan Heath Rawlings, this is The Big Story. Dr. David Fisman is an epidemiologist at the Dalla Lana School of Public Health at the University of Toronto. He’s our favourite person to talk to about horrible pandemics. Hi David.
Dr. Fisman: Hello.
Jordan: I’m just going to ask it straight up. Are we ready for what’s going to happen this winter?
Dr. Fisman: I suspect not quite. There seems to be a little bit of pandemic triumphalism going on right now, certainly in Ontario, where we are doing okay right now, our ICUs are fairly empty. I think we have 15 people in the intensive care unit with COVID in Ontario as of right now. Which is way down. We had a couple hundred, when things were at their worst. And, you know, to a certain extent, I think it’s a very normal human response. People are looking at this and saying, well, you know, we were told it was a big deal. It hasn’t been that big of a deal. But I think when you look at the history of pandemics, the fall wave after a spring or summer emergence tends to be the most severe wave.
Jordan: Why is that?
Dr. Fisman: It’s interesting, eh? So, the thought is those initial smaller waves, what we probably experienced in March and April, those are referred to as Herald waves. But it also happened in 1918 with a summertime emergence that then seemed to go away and then came back with a vengeance that fall. Probably what we’re seeing is what’s called seasonal forcing, which is basically that behavioural and environmental factors oscillate in such a way that they push the reproduction number of the disease up and down. You know, coronaviruses generally seem to be wintertime seasonal. This, we’re sort of doing okay with this thing through a summer. But whatever environmental factors facilitate transmission for flu or for coronaviruses, those tend to come back as the weather gets colder. What exactly that is is unclear. And my colleague, Jonathan Dushoff at McMaster pointed this out about 20 years ago, that this is probably an example of resonance. And, you know, resonance is a phenomenon that we see with, you know, music halls or violins or guitars, right? If you pull a piece of steel taut and plink it, it doesn’t make a particularly pleasing sound. But you put it on a wood resonator box, and all of a sudden you can get nice music. You know, particularly if you– not if I’m doing the plinking, but if you know what you’re doing. But that’s this– Jonathan’s idea is that infectious disease systems are the same. You have viruses that want to oscillate, with a one year period. And then they get tapped by different forcers at their intrinsic oscillatory frequency and it makes them surge in the season when they tend to show up. And that’s, he postulated that that’s the basis of influenza seasonality. That’s what we may be seeing right now in Australia, which if you recall through the spring, seem to really have everything under control with coronavirus. And now when they’re in, you know, in the Melbourne area, and Victoria, in their furthest South state, which is sort of like the furthest North state in the Northern hemisphere, they’re really struggling. Which, you know, may suggest that their seasonal influence at play. As we learn more and more about this virus, you know, there’s the early Japanese observation that it likes close and crowded spaces. Those get harder to avoid in the winter than in the summer. You know, for example, school’s front of mind right now. It’s a lot harder to have outdoor classes in February in Canada, than it is in July, August, September, October. So, you know, the calendar is going to be pushing us indoors. There may be actual environmental influence. It gets drier as the weather gets colder. That’s associated with fine respiratory droplets travelling farther. So an individual who coughs, for example, may be able to infect at longer range. So, you know, right now we’re okay, but this is when we’re supposed to be okay, late summer. So I think we’re probably going to see a surge in the coming months. If I had to guess, it’ll be driven by school opening, because we’ve taken these nice 10 person bubbles that most of us have been in through the summer, and now we’re massively cross-linking those.
Dr. Fisman: So we’re effectively increasing contact numbers in the Ontario population, for example. Which is just creating all kinds of paths for transmission that haven’t existed while we’ve been separated. And we’ll see, you know, we have a few thousand, I believe, more ventilators and potential ventilator beds in Ontario now than we did have, going into this last spring. So we have some preparedness there. We have a lot more knowledge of this virus. Certainly in the intensive care unit, we have ICU doctors in the province who are really good at this. They’re really good at doing the best they can to keep people from dying. And that seems to be an experience where we’ve seen that, there’s published literature at this point. We have medications now, like dexamethazone that have been identified as helping people survive this and also keep them out of the ICU. So there’s a lot of good news. We have a vaccine coming fast. But–
Jordan: But, yeah.
Dr. Fisman: Yeah. Look, I mean, this is, I don’t know if you’ve seen that– this is probably not an appropriate digression. I don’t know if you’ve seen the marvellous thing someone’s done on the internet, where they took the bunny monster scene from Monty Python and the Holy Grail and they turned it into a COVID thing where, you know, Anthony Fauci is Old Tim, the Wizard, who says, ah, it’s a monster, look at the size of those teeth. And the Monty Python, Arthur and his knights say, It’s only a bunny! And he, you know, sends his big knight off to be head the bunny and the bunny, of course, you know, beheads him. And then they all run and attack the bunny, and they’ve got these labels that flash on the screen that say, you know, Florida, Arizona, Tulsa, you know, Tulsa rally and so forth, all the dumb things people have done because they’ve minimized the severity of this virus, and it turns out this virus is as advertised. So we have emerging infection fatality ratio numbers in Ontario that show us that, yeah, the infection fatality ratio in Ontario is about 1%, which is also what it was in Geneva, which is also what it was in Spain, which is also what it was in Belgium, which is also what it was in Sweden. So it’s like, we all think, Oh, we’re special. It’s different here. It’s not different here. It’s a virus. You know, it doesn’t really give a crap what language you speak or, you know, what your hobbies are or what your form of government is. It sees, you’re a culture medium for this thing.
Jordan: So how much of all the stuff that you just described makes a second wave inevitable? And how much of it. Can we mitigate if we’re doing the right things now?
Dr. Fisman: Look, I don’t know is probably the best answer to that question because I’m not Old Tim the Wizard, you know, I can’t look at chicken entrails and say, September is going to look like this. I can tell you that to date this virus, this epidemic has behaved exactly as models said it would behave. And if we throw in some seasonal forcing, and we increase contact numbers, we should see surges. That’s very expected. We also know that transmission risk isn’t homogeneous across society. This is clearly– the Japanese nailed it. It was the three Cs, I think now it’s the four Cs. Closed, close, crowded, and continuous exposure. Exposure for a long time. And that probably reflects the fact that this is an airborne disease at short and long distances indoors. There’s been a huge amount of pushback on that from folks in the medical community saying, well, we don’t see it. We’re not wearing N95 respirators in hospitals and we’re not seeing big outbreaks, and it would be. But that possibly gives us some opportunities where we can think of gatherings, indoor gatherings, almost on a two dimensional surface, where your X axis is, how economically valuable is this activity? You know, from not that valuable to essential for societal functioning.
Jordan: This is the bars versus schools debate.
Dr. Fisman: Yeah. This is bars versus schools. And then, you know, on your Y axis, you could have propensity to facilitate large airborne transmission events, where, you know, somewhere in the top right hand corner of this plane is meat packing plants. Somewhere in the bottom left hand corner I would say is me traipsing through the park. It has no intrinsic economic value to society, although I might enjoy my tripes. So we could think of trying to, you know, deal with risk on a plane like that. Sort of, it’s this 2-D surface, where the things that are low risk– do ’em, sure. Outdoor stuff seems to be fine. Stuff where contact numbers are low, stuff that’s happening in very well ventilated settings is probably fine, much lower risk. You can mitigate that risk further by people wearing good masks for source control. The tougher stuff is schools, you know, essential industry, factories that are continuing to function, and so forth. And there, I think that what we would ideally have done, but we won’t be doing, is really improving engineering in those places, improving ventilation in those places, using testing so that we can see silent infection before we have super spreader events. You know, our window of opportunity is closed already. We had five months to really think like that. And to be fair, understanding has really been evolving over those months. So, no, I think we are going to have some rough times ahead this fall.
Jordan: How much of an uptick is acceptable and how do you monitor that? And is it going to be, you know, wait, wait, wait, wait until it crosses that threshold and then locked down again? Or can we kind of play a whack-a-mole with this?
Dr. Fisman: Yeah, I think we have played whack-a-mole over the summer and that’s been okay. I don’t think we’ll be able to this fall, is my best bet. You know, the goal here is vaccines are coming. You know, let’s say six months. I don’t know what the time horizon is going to be for Canada to get good amounts of vaccine. It’s coming. The scary time is going to be September, October, November, I think. It may stretch into December, January, if we’re good at controlling this, because that flattens and stretches out the wave. The goal here is not to prevent anyone whatsoever from getting infected. The goal is to prevent, you know, mass death events on the order of, you know, things you’ve seen in Italy, in Spain, and in New York and so forth. Where that’s going to happen is, again, if you have ICU fill up and saturate, and then you’re really getting into this terrible situation where people continue to come and you can’t help them, and now you lock down because the ICUs are pretty full. So we’ve done this once and we had to do it once. I think doing it a second time is going to be harder. But I think ultimately this has to be tied to what we’re monitoring. I’ll tell you right now, we do sort of a surveillance report every morning and send it to some folks in government. And what we keep circling back to and emphasizing is the case age is low, right? You’ve got– people seem to have figured out, older people are scared of this, younger people are not scared of this, and they’re behaving according. So what we see is the lion’s share of cases in Ontario right now are in people aged under 40, which I am by no means an advocate for the herd immunity stuff. Again, we’re at 1% infection now in Ontario, it’s really dumb to say let this burn, you’re going to kill a lot of people. But, in terms of folks under 40 getting infected, you know, the risk of death is vastly lower. I mean, there’s a recent meta regression that was done of– sorry. Mehta regression is kind of a regression model that uses data from a bunch of different studies, looking at infection-fatality ratio, that’s death per infection, not death per identified case, which is case fatality. You know, linear regression is this idea that it’s, you know, high school math, where you’re sort of drawing a line that has a slope, and you’re trying to draw that line so at best fits the different data points you have on, again, on an X/Y plane. You can do linear regression on infection-fatality ratios from all these different studies and they fit a straight line really nicely if you log transform them. By log, you know, into their base 10 logs. So, you know, there, ten to the zero would be 1%, ten to the one would be 10%, ten to the two would be a hundred percent, ten to the negative one is 0.1%, and so forth. And you can actually make a nice straight line with infection fatality by age group, by ten-year age increments, so you basically increase a log risk in your likelihood of death with every 10 years you age. So under 50, the risk of dying from this thing is really, really low. It happens. I think they just had a 19 year old die in Montreal. So it does happen. And if you let this burn enough, you’re going to lose 20 year olds and 19 year olds and 30 year olds. But overwhelmingly the people who die are going to be over age 50. And I think you see that in the data, that the per test positivity in Ontario has fallen like a rock in people over age 60. It started to creep up, interestingly, in the last two weeks in people age 50 to 59. But mostly where we’re seeing that positivity is in the 10- to 30-year-olds, who clearly are behaving differently than older people. But what you see is that they seem to be sort of back to normal life, the under thirties, and it’s reflected in the test numbers. They’re the folks getting infected.
Jordan: And I think part of that is, you know, and I understand the psychology behind that is that this is the only summer we’re going to get, and there is likely to be hard times and possible lockdowns in the fall. And they’re trying to get something out of this year.
Dr. Fisman: Yeah. I mean, I think I get it too. And as I say from a population point of view, I’m not into the whole blame and shame thing, because I think there are policy levers that you use to change population behaviour. I don’t think you rely on shaming people or saying, ah, pull up your socks and, you know, show individual responsibility. And it’s a tough ask to say, you know, why don’t you have a garbage, boring summer to protect older individuals who you don’t know from a disease that you don’t believe you have. That’s a fairly dramatic ask. So it’s unsurprising to me that compliance with that has been limited. The difficulty now is of course, with schools and universities, you’re taking these folks who are in the highest stage group, and we’re going to put them in some closed, close and crowded settings. You know, university dorms and schools. In addition to, you know, I mean, thinking about the U of T campus, where I teach, it’s right downtown. As my colleague has said at a panel we had this week, you know, opening dorms in the middle of Toronto, it’s sort of like landing a cruise ship there in terms of ventilation and transmission of COVID. And, you know, obviously students don’t stay locked in dorms. They go to restaurants and grocery stores and parties and so forth. So, you know, to me, it seems pretty likely that we’re going to see a surge.
Jordan: Well, if you were in charge of our preparation right now, and I mention this just because you mentioned, you know, there are policy levers, we could push their strategies. What would we be doing right now that we’re not doing?
Dr. Fisman: I don’t think there’s been a tremendous understanding within public health in Ontario, A) of the degree to which asymptomatic and presymptomatic transmission are important, and that’s gotten us into trouble before with the nursing homes. And I also think there’s been a failure to be able to shift gears on the different ways you use testing. I think a lot of labs are very focused on sort of a medical model where you have someone and you’re trying to diagnose them with a disease, that one person, and then from a public health point of view, you then try to do contact tracing or what have you. What we’re trying to do with testing for surveillance has much less to do with the risk to individuals and much more with a risk to populations in specific places. So when I think about things like, saliva testing, because, you know, it’s very difficult to stick swabs up little children’s noses, you know, even if you don’t have to do nasal pharyngeal swabs, which is sticking the swab in the place, I think we’ve talked about this, that the milk comes through when the milk comes out of your nose when you laugh when you’re drinking it, that’s your nasal pharynx. Swabbing kids, for example, to look at activity in schools is problematic. I mean, that’s, nobody’s idea of a good time. And you’re talking about doing that a couple of times a week. That’s a real problem. So that’s where things like saliva tests would have been very attractive. We won’t be using them at a large scale, because Health Canada’s still not approved them. But they’re there, and they’re being, you know, our professional– you would know this, our professional athletes are using them in the NBA, has stayed pretty safe. You don’t need to identify the individual who is infectious. That’s a signal. And in fact, having negative pools, you know, there’s been a lot of talk of, Oh, you know, those are insensitive, so we’ll miss miss individuals. What you actually are looking for with these pools– with these saliva pools would be an all clear to continue on. So if you’re gathering a vat of spit from small children twice a week in your school, and you’re not seeing a signal and you’re not seeing a signal and you’re not seeing a signal, that’s not dumb. It’s not dumb to do that testing. What that is doing, is that saying there is no COVID in our school right now. Carry on, right? It’s like monitoring the chlorine in your pool. You know, you don’t wait until your pool turns brown and has, you know, a layer of scum on the top and then monitor the chlorine and say, Oh, I should add some chlorine now. You know, it’s sort of maintenance. You’re making sure that there’s an all clear and you can continue operations. And I don’t think that’s understood at all by the folks running Public Health in Ontario. So I think that’s a shame. You know, I’ve had a number of discussions with colleagues over the summer about outdoor education. There are great outdoor education models in Canada. There’s land-based education, which is an Indigenous idea where you actually learn from the land that we live in. And that lends itself absolutely perfectly to COVID because it gets us out of closed spaces. So there’s a lot of pedagogy that can happen outdoors, but we’re of course not leveraging it. We’re putting kids into closed, close and crowded spaces, many of them built in the 1926 with commensurate ventilation infrastructure. So, you know, I think that that’s an unfortunate one. But again, we still don’t have a provincial mask order, that was people kicking and screaming in different health units in Ontario and local medical officers of health doing it. So I think, you know, I mean, I haven’t exactly been, particularly polite or subtle in my remarks about public health leadership at the provincial level. I think it’s been crappy. There’s, you know, there’s a lot that we could have done. Every time the coin is in the air, I feel like our chief medical officer of health calls it in the wrong direction. Whether it’s migrant workers and asymptomatic transmission, whether it was longterm care, whether it was community spread, you know, it’s like almost predictable. And now I think we have a pretty suboptimal school reopening plan, mostly related to the failure to reduce class sizes. Which would have been our one kind of relatively easy way to keep contact numbers low, given that we can’t revamp the ventilation in schools in, you know, two or three weeks. You could go to smaller class sizes, move things more outdoors. And again, you know, there’s this obsession with, will you be one metre apart, two metres apart, it doesn’t matter if you have an airborne cloud of droplets that hang in a poorly ventilated space. So that’s sort of been unfortunate. And of course, you know, again, it’s had the blessing from our chief medical officers of health, as one would expect, because he does seem to have signed off on lots of stuff that I don’t think has been particularly wise or particularly kind to people.
Jordan: Well, that’s why we want to talk to you, so that we know what the experts are thinking, who aren’t working for the government. So thank you for this. And I’m off to resume my stockpiling now.
Dr. Fisman: Take care. It’s nice to talk to you.
Jordan: Dr. David Fisman of the Dalla Lanna School of Public Health. That was The Big Story. I’m sorry I didn’t have better news for you. If you want more heads to thebigstorypodcast.ca, you can find all our previous episodes with David right there. You can also talk to us at @thebigstoryFPN on Twitter, or you can email firstname.lastname@example.org. If you like this podcast, and fine, even if you don’t, you can find us in your podcast player, you can leave us a rating and leave us a review. I hope it’s a good one. Thanks for listening. I’m Jordan Heath Rawlings. We’ll talk tomorrow.
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