COVID-19: The week in review with epidemiologist David Fisman (April 26-May 1) speaks with the University of Toronto professor about the testing, the numbers, and the outlook for Ontario
By Nathaniel Basen - Published on May 01, 2020
Forecasts suggest that most places in Canada are either at peak or past peak in terms of COVID-19. (



David Fisman, a professor of epidemiology at the University of Toronto’s Dalla Lana School of Public Health, has been carefully tracking Ontario’s response to COVID-19. He’s also involved with the province’s coronavirus-modelling group. is checking in with Fisman on an ongoing basis to get his insights into the week that was — and the week ahead — in the province’s fight against the coronavirus. We caught up with him on Thursday afternoon. What do you see in the numbers this week?

David Fisman: So, probably the most interesting conversation this week has been around what comes next in terms of reopening the economy. In our forecasts, it looks like most places in Canada are either at peak or past peak in terms of COVID, so people are trying to imagine a future where we try to get back to some semblance of normality. There is a study in contrast in terms of the different approaches taken by Ontario and Quebec. In a lot of ways, the two provinces have parallel epidemics right now: both are big populous provinces in central Canada; both have a large metropolis that somewhat dominates the conversation and dominates cultural life — Montreal, in Quebec, and Toronto, in Ontario. They’re sort of these big centres of gravity, and within these centres of gravity, things are going less well than they are in the suburbs and the rest of the province. So that’s a parallel. 

Both provinces have ongoing problems with institutional outbreaks in long-term care and hospitals, even as things have somewhat subsided in the community — although Montreal has seen a resurgence, I believe, in the north end of the city. They have an almost identical case-fatality rate — it’s about 6.3 per cent in both places. And they have similar-sized epidemics: Ontario is pushing 20,000 cases and Quebec is almost at the 30,000 marks. That constitutes the majority of cases in Canada. 

So you’ve got these two places where most of the gravity is in Canada in terms of COVID both having press conferences explaining how they’re going to step down from the current level of distancing and taking very different approaches. Ontario has said they’re not going to define a timeline — the premier says it’s a roadmap not a timeline — that they’re going to go by what the epidemic is doing and go cautiously. There’s not plan to reopen schools before the end of May. And Quebec, taking a more accelerated approach, says they’re going to reopen some businesses starting May 4 outside Montreal and May 11 inside Montreal. The dates are laid out. Primary schools are reopening May 11 outside Montreal and May 19 inside Montreal. They’ve really got a strict timeline. 

For me, as an epidemiologist, that’s interesting because I think you can argue either position, but we’ve basically just set up a big Canadian natural experiment. Something to watch moving forward is what happens in those two places that started out in a not-dissimilar position and decided to move forward in sort of opposite ways. I can see the arguments on both sides, but, whatever happens, we’ll learn a lot about the way forward for the next time we have to make these decisions. And what are the arguments on either side?

Fisman: I think you can characterize this as walking on a tightrope. When we model this out, our modelling right now is focused on Ontario, what you anticipate is that weakening distancing — allowing us to have more contact with each other — results pretty predictably in a resurgence of the epidemic. The less you dial down distancing, the longer the window you have before the epidemic comes back. The slower you do this, the more time you buy. But that obviously comes at an economic cost. I guess the argument for dialling things back quickly is that you want people to get back to business, you’re worried about the economic losses that everyone is sustaining right now, and you’re concerned about the social and psychological disfunction that’s coming from this distancing, which is not trivial. It’s a big deal. So how do you calibrate that? That’s why we have elected leaders: they get to make that call, how they want to strike that balance. 

It really is like a tightrope, though. If you go too far in one direction, you’re going to have some terrible health consequences. If you go too far in the other direction, you’re going to have some terrible economic consequences. That’s not easy. So we’ll see who strikes the balance and who gets this right. The likelihood is that this disease is going to be with us for a little while and we’ll have to do this more than once, so it’s important that we pay attention to the next couple of weeks and see how things go. 

Whatever your approach, you have to strengthen your surveillance system. That’s my one criticism right now: I still haven’t seen a clearly articulated plan for how you do public-health surveillance when the epidemic has died down and you’re looking to restart your economy. I think it’s very important to have a clearly articulated plan for how we are going to know when to tighten up distancing again — which we probably will have to do. If this turns out to be a very seasonal disease, and sunshine and warmer temperatures make a big difference — and I’m not expecting that — but, if that is the case, then you still need to know for the fall. Testing has hovered at around 12,000 each day. How would you assess those numbers, and what about the current approach catches your eye? 

Fisman: Yeah, so the testing numbers are up, which is great news. The per cent positive are down, which is also great news. We are now at double the daily test capacity in the province than we were two weeks ago, so there’s no arguing with that. That’s great. My question is, how are we going to use testing moving forward to keep people safe and identify when the disease is resurging? Right now, we are overwhelmingly testing people who feel sick and say, “I have symptoms: please test me — I’m sick.” The question is how we are going to use this same tool for situational awareness, and how we are going to use it for surveillance out in the community. Usually, we would do this with something called sentinel surveillance: if these were normal times, you’d just add COVID testing onto people’s flu tests in doctors’ offices and out-patient clinics. But a lot of those are closed right now, so you can’t necessarily do that. 

The question is, are you going to go to grocery stores or street corners, or set up in parking lots and test random people? That’s probably something we have to figure out. We probably have to figure out strategies for protecting institutions and congregate settings, which we haven’t done a very good job of so far. What you see is that diseases like influenza, it’s very seasonal, but influenza outbreaks in nursing homes happen all year round. If there is seasonality to COVID, then you’ll probably see the same thing — it goes away over the summer in the community, but the nursing homes and the shelters and the congregate settings remain at risk. So that’s the second consideration in terms of how you’re going to use testing differently to protect those settings. That means regular testing of people going into those settings, be they new patients or residents via admission screening; regular testing of health-care workers; regular testing of shelter workers; regular testing of anyone who’s working in long-term-care facilities. I haven’t seen any concrete guidance from the province on that, and it’s important, because, whatever happens in the community, those places are going to remain high risk for more outbreaks. 

The other setting where things got concerning this week — and where one hadn’t seen this previously, and now that we’ve seen it, it’s concerning — is that, as much as you want to fight like hell to keep this out of congregate settings like long-term care, you need to fight like hell to keep this out of isolated northern communities, particularly First Nations communities in the north. 

I think that the worst news in Canada this week was the La Loche outbreak in Saskatchewan, an isolated Indigenous community up where the highway ends in northern Saskatchewan — it has a rip-roaring outbreak. Many of us remember in 2009 with H1N1, when it got into northern Manitoba and into isolated fly-in Indigenous communities, it took a horrible toll in terms of deaths. It’s because these places are isolated that they’ve been protected; if you live in a fly-in community, it’s hard for people to come up and introduce the virus. But that cuts both ways. That means that, if someone does come up and introduce the virus, it’s hellacious. There aren’t a lot of health resources up there. There aren’t intensive-care units in these communities; there aren’t ventilators. It’s hard to get people out — you have to medevac people out by air, and it’s hard to get large numbers of people out. 

So I think the country as a whole really needs to fight like hell to keep COVID out of isolated northern communities. That means a lot of testing, almost like what I said at the nursing homes — everyone who’s going in needs to be tested regularly to keep this thing from being imported. We need to have aggressive use of personal protective items if this gets in. There are already issues with crowding in these communities; it’s very difficult to do social distancing in some of these communities. It’s very difficult to get people out to care. So you really need to do your damnedest to keep the disease out of these communities, and, if it gets in, to get it out as fast as you can. So that’s probably the most important development this week. We’ve discussed this a bit already, but how would you assess Ontario’s public-health authorities this week?

Fisman: I think testing is better. We need to see a better-articulated plan on how surveillance is going to happen — my focus is on Ontario, so I want to see a fully articulated plan in terms of how that will happen. There’s been a lot of emphasis, and it was in the Ontario roadmap, on contact tracing. I’ve been a bit of a Debbie Downer on the contact-tracing side of things. I think that, if there’s a disease where you miss so much — we’re learning from sero-epidemiology that we probably miss between 80 and 90 per cent of cases — and we also have this over-dispersed reproduction number, where cases can cause superspreader events: to me, relying on contact tracing as something that, by itself, is going stop the disease from resurging is a little bit naive. But, you know, that’s a difference of opinion between me and some of my colleagues. And if we can do contact tracing, that much the better. It doesn’t have to be one or the other. If you do contact tracing, that’ll make whatever distancing you have more effective. If you do distancing, that’ll make contact tracing more effective. I’m just skeptical we can get the job done with contact tracing. 

Singapore, for example, which has a very different society and a very approach to privacy than we have in Canada, has sort of gone whole hog on electronic contact tracing, and they just experienced a very big resurgence in COVID related to congregate settings — in their case, dormitories for migrant workers. To me, that reinforces the fact that big gatherings of humans are the vulnerability, and distancing is the approach we know that works. Contact tracing is nice if you can do it, but you can’t bet the farm on contact tracing. 

The other really interesting development that I just learned about today is that the Oxford vaccine group in the U.K. looks like they’re on to something that’s potentially promising. They have, I think it’s a live attenuated virus vaccine for COVID, that’s going into a very squashed-together safety and efficacy trial. 

We talk about phase-two trials as uncontrolled immunogenicity and safety studies, and then phase three is the big randomized control trial: they’re balling that all up into one over the next couple of months with a vaccine they think is promising. Then, in parallel, the Serum Institute of India and AstraZeneca, the big pharma company, have agreed to do the manufacturing of this vaccine, which is untested and unproven, while the trials are going on. So, if the trials are a success, they’ll be ready with a vaccine ready to go into people’s arms in the fall. I’ve never seen anything like that, and that’s a huge gamble for those companies and those governments that are involved — I believe the U.K. government is underwriting that to an extent. But, if that gamble pays off, it will be a major win for the planet. The vaccine debate has been odd to watch: there are people who have said it will take 12 to 18 months, others who say it will take less, and others who say much longer. There seems to be no consensus at all.

Fisman: I’ve been one of the 12-to-18-monthers, and I thought that made me an optimist — 12 to 18 months for a new vaccine that we’ve never had before would be pretty ridiculously fast. With H1N1 in 2009, that was an influenza strain. We know how to make flu vaccines, because we make them every year. That still took six months to get that into people’s arms. To think of a pathogen where we don’t even have a vaccine to start with — we’ve not made one at scale before — to think that could happen on this timeline would never have occurred to me. 

You’re talking about, if this thing emerged in November in China — which, increasingly, it looks as though it did — if we’re getting a vaccine into people’s arms in October, that’s not a timeline I would’ve thought plausible. And there’s risks to this. Vaccines made in a hurry can be associated with adverse affects that don’t get picked up in small trials. You saw that with narcolepsy in 2009; you saw that with Guillain-Barré syndrome in 1976 with swine flu — which is why the trials are important. If you’re going to put this into tens, hundreds of millions of people’s bodies, you need to know it’s a very safe thing. It will be interesting to see this play out. It’s quite a gamble, and it’s a brave gamble, and I appreciate what they’re doing. I hope for all of our sakes that it works out. What else will you be looking for in the next week? 

Fisman: In my very myopic worldview, I’ll be watching Ontario and Quebec, which have these different approaches, and I’ll be very curious to see how this plays out. A huge success story is the Maritimes — all four maritime provinces now have reproduction numbers well below one. So it will be interesting to see Newfoundland and New Brunswick and Nova Scotia — Prince Edward Island doesn’t seem to have allowed any transmission of COVID at all. They have about 1,000 people still on home isolation there. It will be interesting to see over the next week or two how the Maritimes try to restart their economies. They’re the real Canadian success stories right now.

I think the provinces out west, there’s been a bit of an inversion, because Alberta, Manitoba, British Columbia, and Saskatchewan were really quick, initially, to control spread, and now they’re dealing with resurgences — all those provinces are. The hottest of the hot spots seems to be Saskatchewan right now. There’s a lot of sortof western enthusiasm, in particular in southern Alberta, for opening the economy back up — the leaders there are under a substantial amount of pressure to let people get back to work. But, of course, it’s a little bit like — I sort of mocked an editorial by Thomas Friedman in the New York Times about a month ago this idea of restarting your economy while the epidemic is raging is sort of like rebuilding one side of your house while the other one is still on fire. 

To me, as an epidemiologist, that’s what that approach is: spraying water on one side of the house because it’s not in flames. That doesn’t make any sense. So we’ll see how the west does; hopefully, it continues to settle down. Overall, our Canadian outlook is pretty promising, and it’s been very stable for maybe the past two weeks. Things look like they’ll be pretty flat by the second week of May. I hope that that forecast comes true.

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