Jordan: Today, our guest is going to use the P word just so you’re prepared. And know prepared is sadly not the P word. That word obviously is pandemic and there is currently a mostly superficial debate over whether or not to use it to describe the spread of the Coronavirus, CoVid-19. The debate is mostly superficial because while public health bodies go back and forth on it, the actual public, who are scared, just hear one terrifying news report after another every day.
News Clip: Canada has recorded a tense case of CoVid-19 presumptive at this point… More than 50 cases here in the US and global fears growing… And today the DOW plunging… The World Health Organization now says there are more new cases of the coronavirus outside China, than inside that country… There are 50 countries and regions now affected, and as you can see, there’s CoVid-19 cases reported in every continent except Antarctica.
Jordan: Thus far, according to official numbers, Canada has largely been spared. But until recently, lots of other places around the world seemed exactly that way too. And now they’re not. So what happens next here and around the world? What do we know now about this disease and how it spreads and who it attacks that we didn’t know last month when it was just emerging? What should sensible Canadians do right now today? What should they plan for in the coming weeks and months? And what exactly does decades of expert research and models tell us what is likely to happen from here? And how does the world prepare for that? 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. His work puts him on the front lines of Toronto and Canada’s effort to battle this virus. Hi, David.
David: Hello. Thanks for having me back. Despite my, uh, faulty prediction last time.
Jordan: We won’t start, we won’t call it faulty because it was based on what we knew at the time. But we wanted to have you back because this has been evolving. And the last time you were on, we talked about CoVid-19, which wasn’t called that at the time. And you said kind of, the quote that stuck with me was, we’ve seen this movie before and now. I feel like I have seen this movie before, but it was called outbreak and a lot of people died.
David: No, I think, I think for good or ill, it is a sequel, but the script writers seem to have been more creative than we– than I certainly expected last week. And I have to go through– I’m not a psychologist, but I have been trying to learn about cognitive biases, because I think that in my bad takes on this, I’ve anchored on what I thought I knew based on prior epidemics, and this has turned out to be different in important ways. If we had recorded this a week ago on February 20th, I actually would have stuck to my guns. Um, because as recently as the middle of last week, I really felt like this was a massive epidemic, but the aggressive social distancing in China sort of had locked it down. And, um, I was quite smug with the class I teach at UofT and showed them, uh, model projections and those model projections for China are actually right. So China seems to have this largely contained within China. The difficulty is, it was like a forest fire in China that sent off all these sparks around the world, and a lot of countries contained the sparks. But it turns out that a lot of countries didn’t. So what changed for me last week was the recognition in Canada and simultaneously in Lebanon and in the United Arab Emirates, CoVid-19 cases with travel histories linking them to Iran, which at that time, I’m not even sure if at that time Iran had any cases, but had single-digit cases certainly by the end of last week, and several of those single digit cases were already dead. So given the leg between infection and, um, demise with this thing, the high fraction of deaths told you that this was already an old epidemic. And we ran the numbers over the weekend with some colleagues, some colleagues named Kamran Khan, Isaac Bogoch, my colleague Ashley Chu was the person who wrote this short paper, and in Ashley’s analysis, she looked at travel rankings for, um, uh, countries in terms of their closeness to Iran. Canada’s number 31. You know, so there’s 30 countries on the list higher than us, which include places with lousy public health systems like Syria, like Iraq, places that have been through civil conflict and that effectively are very vulnerable to infectious disease, cause they wouldn’t be able to identify it if it was there. And they had no cases, which is mathematically implausible that Canada’s importing cases, but Syria and Iraq have none. So that right there told you, uh oh. This is around and we’re not seeing it. The day after we did that analysis, Kuwait, Oman, Bahrain, Afghanistan, and Iraq said, Oh, we have cases. So we reran the analysis. And the TLDR on this is the estimated epidemic size, to see that volume of exported cases based on travel volumes, is an epidemic of about 20,000-25,000 cases, which is a huge epidemic. And even now, I think Iran is up to a couple of hundred cases that they’ve officially reported, it’s a tiny fraction of what’s actually going on. And this is disseminated. So it’s in, it’s in Afghanistan. It’s in Pakistan. It’s not in Syria, but nobody believes that. Uh, it’s not in Yemen, but nobody believes that. We haven’t had a single case in Indonesia, which has fairly close ties to Southern China. But I don’t think many epidemiologists believe that Indonesia has no cases. So, you know, Iran locked this down. Singapore had an outbreak and controlled it. But we now have outbreaks in, uh, South Korea that, the Korean health system’s very competent and they seem to be struggling to contain. We have a large outbreak in Northern Italy, which also looks large and old, like the Iranian outbreak with a high fraction of deaths. So this seems to be everywhere. And I think, and this is really, I mean, this is literally the last six days. So I think China got the job done locally, but you know, the cat’s out of the bag, or that’s the ballgame or whatever, whatever metaphor.
Jordan: What happens when the cat is out of the bag for Canadians for sure, but in countries that haven’t seen it yet? You know, there was some controversy in the United States when one of the officials dealing with it said, it’s a matter of when, not if.
David: I think what you see there, to be brutally Frank is kind of the toxicity of the Trump administration and the White House where you have a senior public health official, just stating a plain truth. This is Nancy Messonnier of the CDC. Absolutely. It’s a matter of when, not if. People are acknowledging that in Canada now too. That’s just the plain truth. And you get the rapid pushback from the White House saying, no, no, no, it’s not going on here. That was undercut last night because we now have a reported case in, um, in Northern California. The details came out last night that this is someone without a known link to an area outside the United States who was transferred to UCDavis on February 19th, already intubated and on a ventilator. So already in intensive care. My fear in Canada, and I think many physicians, many of my colleagues here in Canada, is that we’re not looking aggressively enough for this in people without known travel linkage to areas of the world that we think this is spreading in. Because what Iran shows you is, it’s the quiet places are the problem. And so we need to be doing more to surveil this in primary care clinics and emergency rooms. And as was the case in you at UCDavis, test people with unexplained respiratory failure. Cause the last thing you want is for this to come to light because you have a SARS like event with a hospital outbreak.
Jordan: When you hear officials say, when not if, in your world, what does wen look like? Like what is that?
David: Yeah. No, I mean look, to my mind, there are two cases in Iran out of, I think we’re at 12 recognized imported cases in Canada. I think possibly two of those are secondary transmissions in Canada. Two of the cases are imported from Canada. The other imported cases have links to China. So the first case from Iran sounds like may have even been ill on the flight, presented quite promptly, was diagnosed. It sounds, reading the tea leaves, I wasn’t involved in care here, it sounds like the second case had been ill since February 15th and was twig to come into Sunnybrook and get tested by the fact that people were saying, Oh, you know, this may be around in folks who have traveled to Iran. So that to me, you know, those are the two you found. So the question is, well, where are the people you didn’t find? And what’s going to happen with those? So one of the messed up things about coronavirus, certainly with SARS and with Ebola, is there’s something called the Pareto principle, which is like the 80-20 rule. You know, 80% of the stuff comes from 20% of the people. For me as a professor, I’m not going to say 80-20 I’m going to say, 99% of my headaches, cause people will hear this, 99% of my headaches come from 1% of my students because my students are awesome. But that’s an example of a Pareto distributed process. In the context of infectious diseases that means, let’s say 80% of the secondary cases come from 20% of the primary cases. That’s something that’s called an over distributed Rnot, or a Pareto distributed Rnot. Some people are just better at spreading. Some people are better at spreading and some places are better to spread. So you look at the Korean Church, the mega church where this seems to have taken off like approximately like a rocket, and there’s something about their style of worship, I don’t know too much, it sounds like it involves a fair bit of physical contact. It seems to have been very, very good at transmitting this, and we had that in Toronto during SARS with religious communities as well. Hospitals seem to be very good places for super spreader events. You know, a person goes into respiratory failure and infects 14, 15, 17 healthcare workers all at once as they get intubated and then you get the dead, ends the zeros. So you know, this is kind of like tick, tick, tick, tick. You’re waiting for the boom. And we don’t know if the boom’s going to come yet, but I think the boom is probably going to come over the next couple of weeks. I don’t know if it’s tomorrow or three weeks from now.
Jordan: And what happens in Canada when that boom hits, what do we do?
David: So, so that’s, that’s a great question. I think what we do and what I had hoped and what I’d actually said publicly at an event at U of T last night, is I’d like to see some clear messaging from public health authorities, I think at the federal level it’s happening, here in Ontario, that not only reflects the situation as of February 27th, but shows a little bit of situational awareness and forward thinking. So right now, or as of yesterday, the official messaging on the public health Ontario website said there’s no transmission in Ontario. As far as I know, that’s a true statement. Based on what’s happening in other places in the world, and we can’t cut ourselves off from everywhere else in the world, I think it’s appropriate to look forward a few weeks. And to think about, you know, are we gonna actually try to contain this in Canada? Are we going to go full Huabei and lock places down? Or I guess full Lombardi now, and lock places down? Well, if we’re going to try and do that, uh, at least transiently to buy some time, you need to tell people that because they need to prepare. They need to have supplies in their house in case their neighborhood gets locked down. They need to go to the grocery store and get some canned stuff in case the grocery store is closed down. They need to think about how they’re going to balance work and kids, if schools get shut down. So you need to tell people that upfront, that there could be fairly large scale social distancing measures. I think thinking a little bit ahead can be helpful for people because we need to organize, and I think that applies at the community level and it also applies in hospitals. And I know there are a lot of folks thinking about this now, and calling out for a little bit clearer guidance. The four S’s of pandemic planning are space stuff, staff and systems. So we’d hope that at some levels of government, people are thinking through supply chain. Do we have enough ventilators? Where will we put people when the hospitals are full? Um, uh, do we have enough staff? What are we going to do if people get scared and don’t show up for work? What are we going to do if health care workers get sick and need to be cared for? How are we gonna communicate? How are we going to do surveillance? How are we going to keep our critical supplies and you know, bare necessities flowing during what’s going to be a very disruptive time? There’s some for– you can, you can be a little bit forward thinking. So I think we’ll probably pass through a period where we attempt to contain this in Canada. And it’s fairly aggressive, you know, I don’t think we can go full Huabei, we’re not an authoritarian country like China is, but I think we’ll try and, um, I think that probably won’t work because it’s not contained in lots of other places. And it’ll keep coming. And then I think we’ll settle into some sort of modus vivendi. It’s not the apocalypse, it’s not contagion. Um, it is probably the worst flu season you have ever seen, kind of on steroids, and then times 10 in terms of case fatality. Because the case fatality looks like it’s settling out at something like 10 to 20 times worse than a bad flu year. And what happens–
Jordan: That sounds horrible.
David: It is horrible. And, and anyone who works in healthcare in Ontario will tell you that when we have a very bad flu year, our hospitals are stuffed to the bursting with sick patients and we get a log jam. So we have to be thinking about that kind of surge. Again, summertime may buy us a little bit of time because we’ll see how seasonal or not seasonal this turns out to be.
Jordan: Well, that was my next question, like Donald Trump, and not to, not to sound like a Trump in asking this question, but one of the things that he said that seems like it makes it kind of crude sense is that like if we can just hold out until the weather gets warmer, this’ll go away and we’ll be okay.
David: No, I mean that, that’s an extremely wrong statement.
Jordan: Well okay, stop on that for a minute because I have a followup. You mentioned a minute ago that warmer weather, the summer could buy us some time. So what role does weather play in the spread of this virus?
David: Seasonality is fascinating. There, there are two components here. One is, you know, you think about high school math and what a sine wave looks like. We think the reproduction numbers for a bunch of infectious diseases look like sine waves. So they go up and down through the year. They oscillate. The difficulty with pandemic diseases, which this is one, I’ll use the P word, is that what makes them so nasty is the whole population susceptible to the disease and in as much as the reproduction number is a function, both of its basic components, contact rates, duration of transmissibility, infectivity, it’s also the effect of reproduction number’s also a function of what fraction of the population susceptible to disease. Which right now in Canada, it’s approximately a hundred percent. What happens is once a disease becomes endemic, like influenza, we have some carry over of partial immunity year to year, which damps down that reproduction number, which means that as transmission oscillates, because of environmental factors, schools opening and closing and so forth, in some seasons that R not gets, the R effective, sorry, it gets pushed below one and the outbreak goes away. I think you have a nice example of what could happen from H1N1, which was a much less severe, much less virulent infection. Um, we had a big wave in April in Ontario. We don’t get flu in April here. We get flu in the winter. So that was an out of season wave, uh, which is also called a Herald wave in pandemics that you get these out of season, funnily timed, uh, epidemics. So you know, when I say, I think some are, may buy us a little bit of time, we have natural social distancing schools closed. People are outside, they’re less indoors cramped together, you have glorious ultraviolet B radiation all around us that does nasty things to the genetic material of bacteria and viruses. So that’s awesome. It’s nature’s disinfectant. That said, if we get a hiatus during summer that buys us some time, allows us to build surge capacity, allows us to plan for fall because we’re all susceptible. And this won’t go away. You know, if it bounces down to the Southern hemisphere, you’ll get reintroduced to the Northern hemisphere. So we can flatten this epidemic curve and stretch it out. But I don’t think at this point we duck this anymore.
Jordan: So if that means that as the headline of one particularly terrifying article said, this week we’re all going to get this, or at least many of us are…
David: Yeah.
Jordan: What is it going to look like? What do we know now about what the disease does? How it, who it impacts most, that kind of stuff that we didn’t know when it was just emerging?
David: So, so the signature of this disease seems to be age-related, a increased risk of mortality, which is pretty scary. Um, there are a lot of diseases that are like this. Folks won’t probably have heard of H7N9 influenza, which was a bird flu strain that emerged in China a couple of years ago, was exactly like this. Uh, we have a disease all the time in Ontario called Legionella, which is a bacterial disease, which looks like this. We all get exposed to Legionella is all the time. They’re ubiquitous in our environment, but nobody gets the disease until they’re 50 in Ontario. And something happens to your immune system after age 50, that suddenly, um, seems to impede your ability to respond to these infections. And I think people are going to continue to argue about the absolute case fatality for a while for CoVid, because we don’t really know the true denominator, and we’re going to have to wait for what are called serology studies to find that out. But in terms of the relative risk of death in China, it’s about 1% for people my age. That’s the 50 year olds. It goes up to 3% for the 60 year olds, it goes up to 7% for the 70 year olds, and then it’s 15% for those over 80. So you get this Mark takeoff and then, under, you know, a hardy Mazel Tov to you, 30 something year old guy, you know, once you’re under 50 it really dwindles away to the sub 1% which is not to say they haven’t had deaths in younger people, it’s just much less common. And to me as a parent, the silver lining in all of this is that kids seem to be just fine.
Jordan: Even young kids who have the same problems with the flu?
David: Especially young kids so far. Um, one of the interesting things is there’s been a marked under recognition of infection in kids. There was– China CDC put a paper paper out last week on the first, uh, 44,000 or so virologically confirmed cases. 1% of those are in children under 10. I don’t think that means that kids are uninfectable, which, a very smart epidemiologist, I recently reviewed a paper by very smart epidemiologist who said, you know, we modeled this, but we dropped kids because they can’t be infected. Yeah. It’s not the first virus– it seems like *sniff* it doesn’t, it doesn’t smell right. The, um, so I think that’s, that’s implausible. And indeed, there are infected kids. And this would be, um, consistent with other viral diseases like hepatitis A and chickenpox where kids get infected but get much milder disease than adults. So there’s something about infecting a grownup with a disease that kids get that, that makes the outcome worse. Uh, so kids get hepatitis A a lot and, and seldom get very ill. Adults get hepatitis A and, and are a much greater risk of things like liver failure. So something happens to us immunologically, as we age, that puts us at greater and greater risk. Now, that doesn’t mean kids aren’t epidemiologically important. And I think we may have a bit of an “aha” moment coming with this in the, in the scientific literature, in the coming weeks and months, that– and this is important in terms of school closure– that with a lot of respiratory viral diseases, kids don’t really contribute a lot to mortality burden, uh, but they contribute a lot to transmission. So if you look at flu waves, a colleague John Brownstein has done this in Boston, you look at flu waves by age and Boston based on primary care testing data. It’s a series of waves that go through the population from youngest to oldest. And so the oldest or the oldest folks are kind of cut off, the youngest folks, I mean, you’re a parent, you know what kids are like both with their bodily secretions and in terms of how they play and interact. They are just amazing vectors for communicable disease. So we hug them even when they have kind of this transparent goo coming out of their noses. You know, you’re so cute, I can’t, you know, um, and, and, and I think that’s a, that’s a marvellously effective way to transmit a disease.
Jordan: And there’s a kid gets over it and–
David: And then the kid gets over it–
Jordan: And the adult hangs on.
David: To me, that’s the silver lining in terms of kids being spared. And again, that’s very consistent with what we saw during SARS, which was kids didn’t get that sick.
Jordan: Now that we’ve done all the, uh, thoroughly terrifying stuff, what should Canadians do, who are listening to this? You mentioned earlier, uh, should we be telling them to hit their grocery store and bring home canned foods? Have we reached that stage yet? Should we just be planning to potentially get there?
David: You know what, there, there are a few things that I think people have to think of. They have to think about the more vulnerable people in their lives, which in this case is older people. Not to be too grim about this, but we all should be having conversations about end of life care and what people want. As you say, 1% is a large number. If we have a, you know, a cumulative attack rate, by the time this is over, if 30% of the population, that’s a lot of people, and if 1% of those folks die, that’s a lot of deaths. Um, so we should be having those conversations about, if you get sick with this, what would you want us to do? I think on the medical side, people are going to have to have these conversations about, you know, if we have one ventilator and two patients, how are we going to decide who gets that? That’s over on the medical side. On the public side. I think people should have emergency kits in their house. I’ll– a longstanding red cross recommendation. You should have some food that doesn’t spoil. You should have a flashlight and batteries. You should have a radio with batteries. You know, none of this stuff is pandemic specific. Think ahead about how you’re going to interact with people, how you’re going to live your work life. Do you have to go in? Can you video conference? Can you tela-conference. I mean, we’re blessed in the sense that we can do a lot of work at this point without interacting face to face. Remember, this is large droplet transmitted. Masks aren’t going to help you except in as much as they keep your hands off your face. So this is all about limiting contact, disinfecting dirty surfaces. If you’re like me and you have to ride the subway to get around, have some hand sanitizer, clean your hands when you get off. So social distancing and hand hygiene are going to help you a lot. And because this is such a low reproduction number disease, remember, on average, each old case only makes one new case. If you reduce transmissibility by half, that makes a huge impact on the spread of this disease. So I think, you know, self protection, thinking about how you might distance yourself, uh, thinking about your future work and travel plans and how those might be affected, um, having some emergency supplies in your house and having some important conversations with your, with your family about what happens if this is an emergency and if people get sick, what do they, what do they want done?
Jordan: On that uh, entirely cheerful note. Thanks David for helping us with this.
David: Thanks so much for having me.
Jordan: Dr. David Fisman and epidemiologist at the University of Toronto. That was The Big Story. If you’d like more, you know where they are, thebigstorypodcast.ca. We’re on Twitter at @thebigstoryfpn, tell us if we scared you, we’re sorry if we did. I’m scared too. You can also find us in your favourite podcast player, Apple, Google, Stitcher, Spotify, Dog Catcher. That is a podcast player. I did not make it up. Claire Brassard is the lead producer of The Big Story. Ryan Clarke and Stefanie Phillips are our associate producers. Annalise Nielsen is our digital editor. Thanks for listening. I’m Jordan Heath Rawlings and we will talk Monday, when hopefully the numbers have gone down.
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