What do we really know about the Omicron variant? And what’s the best way to stop it?

Jordan I’m not going to waste your time with a monologue because you don’t need to hear much from me about this.

Omicron News Clips …a variant of concern, and they’re calling it “Omicron”…

…Omicron, with its spiky profile, has now emerged in dozens of places, Japan and Israel, which closed borders. Also in France, UK, Australia, Brazil, Canada and Germany…

…we are banning the entry of foreign nationals into Canada that have traveled through Southern Africa in the last 14 days…

Jordan I don’t know about you, but the news of the Omicron variant has filled me with a little bit of despair. It can seem at times that we are so close to returning to some semblance of normalcy, only to have a new problem cause us to take two steps back. So what do we know about this new variant? What are we still learning? And when will we learn it? What do the smartest infectious disease experts in the world suspect right now? How far could this set us back? And on the other hand, what is the one big change Canada could make in our COVID approach that could help get us through the final mile of this pandemic, however tough it might be?

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. We’ve talked to him frequently during this pandemic, often, when something bad has just happened. Hello, Dr. Fisman.

Dr. Fisman Hello. Good morning.

Jordan Thank you so much for joining us. I want to ask you very quickly, because we’re going to get into what we know and don’t know about the Omicron variant. But first, when you first saw or heard the news about this variant rising, what was your initial reaction?

Dr. Fisman I think I was concerned partly because of the information sources and because credible people were concerned. It makes you more concerned. There’s been a lot of new variants that have popped up over the last year where there have been genetically distinct strains, and there have been a couple of media articles about them, and maybe someone put something on Twitter and said, oh, this could be a big deal. A lot of those things haven’t really panned out or turned out to be much of anything.

What you had here were some really credible scientists, both from the UK and South Africa coming forward, both with sequencing data in terms of what the genetic code is for this variant, and also with growth curves from South Africa, where it looks as though this thing is suddenly exploding in a country that’s been through some very rough times with the pandemic, but looked as though it was into a bit of a quiescent period. And it’s also summertime in South Africa as well, so it’s a bit of an offseason development. So I was quite concerned, and I continue to be, although we’re in a little bit less of an information vacuum than we were in five days ago. The pace at which knowledge changes is pretty astounding.

Jordan So what have we learned then, in the last five days or so that’s either different from or confirming those initial concerned reports?

Dr. Fisman I think there’s some really credible estimates of increased growth rates with this variant. And then folks, like there’s a wonderful epidemiologist mathematician in Switzerland named Christian Althaus, and Christian had a very nice articulation of when we look at something that’s growing faster in the context of a pandemic that’s been around for a while, there are really two things that can juice growth up. One is if it’s just intrinsically more infectious, and we saw that with Delta. All else equal, Delta is going to out-infect other strains, and that’s why it’s out-competed all the other variants in Canada and displaced them. But the other thing that you have, I think this thing has something like 32 different amino acid substitutions. So it’s really quite a different spike protein on the outside of the virus, which is one of the important, they call it an antigenic determinant. It’s sort of like the pattern that gets recognized by an immune response on the outside of the virus is very different. So you’d worry that an immune response would kind of miss this thing. And vaccination of prior infection wouldn’t protect someone as well. And that’s the other thing that can create the appearance of juiced up growth.

And as Christian pointed out, South Africa has had very high attack rates. They’ve had a lot of deaths around 300,000 deaths. So from that, you can back estimate what fraction of people in South Africa must have been infected by now. And it’s a very, very high fraction. But South Africa is actually an outlier in the African context, and maybe we can get into this, where they’re at nearly 30% of their population vaccinated, which is way above a lot of their neighbouring countries in Africa. So you have a fair bit of immunity or prior immune experience around this population. And yet you have this thing taking off like gangbusters, that raises the possibility that it’s growing fast because it evades an immune response. It’s probably a combination of the two.

There’s some preliminary data that was out in the Israeli media yesterday, suggesting that in the EU and South Africa, they’ve actually managed to do some quick analyses that do suggest that vaccine is quite protective still. So, a little bit of diminished protection, but it’s still protective. But in unvaccinated people, just as we saw going from Wuhan variant to Alpha to Delta to this thing, it does seem that in unvaccinated people, this is more likely to cause severe illness, something like two and a half times more likely. That’s very preliminary. But it does look as though it’s behaving as you would expect, based on the fact that this thing is peppered with mutations that confer the ability to evade a host immune response, increased binding. There are a bunch of different mutations on this thing that are thought to make viruses more virulent and better infectors. And it’s got a whole slew of them. So it looks like the preliminary data looks like it’s behaving much as you would expect, but the silver lining is people who are vaccinated seem to still be very highly protected, both against infection and against severe illness.

Jordan I think what a lot of people listening to this might want to know is, how should this materially change their own approach here in Canada in terms of risk assessment, public behaviours, this kind of stuff? So far, we haven’t seen massive changes from any of the provincial governments. So I think people are kind of nervous about this, and they feel a little bit on their own.

Dr. Fisman Right. So there are a couple of things. I mean, one thing to maybe talk about is what we perhaps ought not to do or ought not to do for too long. There’s a guy named Jorge Caballero who is an infectious disease expert in the US who’s done some really neat stuff looking at where on Earth, aside from South Africa, has this thing emerged and he’s finding it in sequence banks in the US, in European countries. The UK, at this point has acknowledged that they have community transmission of Omicron. Even our imported cases into Canada, the two initial cases in Ottawa were travellers from Nigeria, which is take my word for it is pretty far from South Africa. This idea that you have this short list of countries where you’re restricting travel, restrictions on travel probably only makes sense if you actually have a gradient in risk, and if it’s everywhere, then arbitrarily cutting off travel from a couple of countries doesn’t make much sense.

What’s probably more appropriate, and we haven’t done a ton of this in Canada is beefing up border controls, including testing at the border and proper quarantine for international travellers. But there’s been a tremendous reluctance to do that. So it’s interesting to see testing has been reinstated at the airport, except if people are coming from the United States. Well, that’s a big loophole right there. So there’s a little bit of probably theatre at this point, and hopefully Canada will start to scale back on some of these initial reactions, which I think when you don’t have information, it’s appropriate to act and gather information. But now we know a bit more.

In terms of what we can do to protect ourselves, it really is, as you say, much the same sorts of things one would have said a week ago. Canada’s a laggard on providing third doses in terms of vaccine. It’s pretty clear that this is a three dose vaccine. The fact that we’ve gotten a little bit of extra mileage out of spacing some of our doses out is great, but it’s still a three dose vaccine in Canadians, as it is in other people in other countries, and we know that efficacy does wane over time. So we need to open up boosting in Canada and stop throwing vaccine in the garbage. Vaccinating kids, we’re now getting into that. That’s very important.

And then the other low hanging fruit, we’ve sort of all the way along been kind of fighting this with one arm tied behind our back, about two, three weeks ago, you actually had some movement in terms of acknowledgement of how this predominantly spreads. It spreads via aerosol.

Jordan Well, this is why we wanted to talk to you originally. We even booked you for this conversation before the variant showed up to talk about exactly this, about the longtime coming admission of aerosol transmission. So I guess I want to ask you on that note, when did you and your colleagues first suspect or first start to see data that this was aerosol driven? How long ago was that?

Dr. Fisman When did I see it and when did I understand what it meant? I mean, I saw it along with everybody back in February 2020 with the Diamond Princess cruise ship, where you had this disease moving around a cruise ship and spreading among people who were in no direct contact with each other. The Japanese by March 2020 were noting that COVID was way more transmissible indoors than outdoors. That suggests aerosol transmission. I think in September 2020, I did a talk for the chief medical Officers of Health of the different provinces through Public Health Agency of Canada on how this being aerosol solves a lot of the mysteries in terms of transmission of COVID. This very skewed reproduction number we had with original COVID, where often it was non infectious, but you could have super spreader events. How you seem to have these remarkable super spreader events in particular locations, like at choir practices, for example, or karaoke bars, which really suggested that this is about aerosolization.

Around that time, a bunch of aerosol scientists, including Don Milton, who’s at University of Maryland and Lydia Morawska from Australia, wrote this open letter to World Health Organization saying, it’s aerosol. It’s very clearly this is transmitting via aerosol. That’s, in a sense, great news because it opens up a whole toolkit. And the response from the WHO and from national public health agencies, including from Public Health Agency of Canada, was basically to blow this off. Pardon the pun, I guess. In terms of WHO there’s an infamous tweet that’s still up that says COVID is not airborne with caps lock on.

It’s gotten increasingly awkward because folks who say, oh, it’s these large droplets, it’s spatter and snot at close distance so you don’t need airborne precautions, have been progressively moving the goalposts in terms of what you would need to say for this to be an airborne transmitted disease. I mean, at this point, what we know is you can transmit this around corners, big splatter droplets don’t go around corners. We know this goes through ducts. We know that the reproduction number is now the same for Delta as it was for chicken pox. And chicken pox is widely acknowledged to be aerosol. We know we can culture this virus from the air, actually get live virus from air samples that’s been done a number of times now. So every time a new paper comes out, that sort of is knocking one last nail into the idea that this is just transmitted through close contact and droplets, you’ll have a moving of the goalposts.

And I think the most embarrassing moving of the goal post, frankly, was a group connected to the WHO started proposing that, well, you can’t say it’s aerosol until we do human challenge studies with this virulent virus. So we give it to people on purpose and then watch what happens in a sealed room or something like that. In 1948, we had the declaration of Helsinki after the Nuremberg doctors trial, that sort of said we don’t do stuff like that. It’s pointless and superfluous when we have this whole database now. But you have folks who are just total bitter enders. And I think it comes down to a few things. A lot of these people have had illustrious careers in science and medicine. But part of this is just this inability to say, yeah, I was wrong, we need to change.

And what you see is I think the more senior folks in my field, infectious disease, just really going down with the ship. The more junior folks, because medicine is so hierarchical, I think for the most part, a lot of them do get it. I think for many of them, it’s very hard to say this out loud because medicine is terribly hierarchical. I think it’s interesting because you’ve got the issue of saving face and credibility: is it more important to you to be right than to protect people during a pandemic?

There are economic aspects to this as well. And you can see, even with Dr. Tam, who sort of all but said, this is airborne. She said it hangs in the air like smoking, it’s borne by air. Do we have a more abbreviated formulation for that concept? Yes, we do. The word airborne would mean the same thing. But a lot of these senior folks have studiously avoided the word airborne because airborne has regulatory implications.

Jordan Why was there this resistance? I just looked, by the way, just to make sure it was November 4 in which Theresa Tam sent out a series of tweets that indicated that COVID was transmitted through aerosol or implied that anyway. So that is 18 months later, and I understand not wanting to be wrong. I understand that’s a natural urge. But the bigger concept to me is if we actually put that on paper and put it into public health regulations, what has to change immediately? And does the resistance come from that?

Dr. Fisman Yeah, it does. In terms of what needs to change. I think the most important thing in terms of what Dr. Tam said is it gives people an appropriate mental model. So, for example, when I look at the news just to pick at random, for instance, there’s a super spreader event that happened in Saint John, New Brunswick this past week. There’s a get together at a Legion Hall. One of the Legion members, I believe, has lung cancer, and it’s a get together to raise money for this Legionnaire. And they were very cautious. Everybody had to be two dose vaccinated. And as one of the organizers said, they followed all the public health guidance. Well, they did, and that’s the problem is the public health guidance is silly. The public health guidance is very much about surfaces and touch and physical distance from one another, which is helpful in terms of aerosol. Again, getting back to smoke, it’s going to be more concentrated near someone than far from someone. But what they don’t mention is ventilation.

And so you look at this kind of, it’s a typical Legion Hall. It’s this kind of red brick kind of square building with a couple of windows in it. And you imagine there’s probably not a lot of air exchange there. You have an individual in the room. They had an open bar. So people are taking off their masks to drink, and presumably there’s some singing, some talking and laughing. So you’ve got aerosolization going on in this closed space with poor ventilation, and you’ve got a super spreader event. Now you’ve got 20 people infected and reading between the lines and the media accounts. It sounds like these are older guys, some of whom are going to get quite sick from COVID. So if you change people’s mental model, you can have that gathering at the Legion Hall, but you can do it safely.

You can use something like a carbon dioxide monitor to know what the CO2 is like. If it’s poorly ventilated, maybe it’s just a matter of cracking the windows that you have. That can be quite dramatic. But maybe you want to get a few HEPA filters in there and just suck these viral particles out of the air. We have Canadian manufacturers now of highly efficient respirators that fit to your face. People need to understand that’s actually important. Those things really do work to filter out aerosol. And you don’t have to be vulnerable. We don’t have to have lockdowns. We don’t have to have these case counts rise to a level where they’re threatening our health system, and we have to shut things down. If we use the science that we have, this all becomes much easier. That’s what the science is for. It’s to show us how to deal with this in a surgical way.

It is a bit depressing because you have these authority figures who are saying things that are not really connected to reality. They’re connected to it’s almost like a religious sect or something where there are these beliefs that people who belong to the sect must have in order to be accepted by the other sect members. And even if they’re irrational, it’s part of how you belong to the sect. But in terms of the resources, once people say the “A” word and it’s airborne, there are protections for workers, they would need to change how they deal with this in hospitals, and for hospitals, the existing airborne precautions. We don’t have the resources to manage COVID the way we would manage measles or tuberculosis, which best practice is going to be put that individual in what’s called a negative pressure isolation room, so air doesn’t come out of there, it gets sucked in.

If you have 30 or 40 COVID patients, which sounds like what’s happening in New Brunswick now, with this outbreak in this hospital, you don’t have enough negative pressure isolation rooms. So you may actually have to do things differently and come up with new protocols. But those are doable. Those are things you can do. But the jumping off point is you actually have to understand the science and how this thing spreads.

Jordan Thank you, by the way, for explaining that, because I feel like that is a more detailed explanation than I’ve had, certainly from anybody in a position of authority at public health. The last thing that I want to ask you about, and it kind of plays off what you just said. It sort of seems depressing that we’re still doing this 18 months later. There’s been a lot of talk around the new variant and rising cases that A: we’re back to square one or this variant could put us back to square one. And I’m sure anybody hearing that is going to have this sinking feeling in their stomach. And I know that when we’ve talked before, you’ve said to me, pandemics end and that’s something I’ve clung to during the peaks of the waves. Where are we in that phase now? Obviously, it hasn’t ended as quickly as we would like, what are the chances that this could set us significantly back? And if it’s not going to and we’re still kind of in the normal pandemic phase, how long is left in that phase?

Dr. Fisman Yeah. So the short answer is, I don’t know, because we’ve known about Omicron for five days or so. The honest answer to that is, I don’t know. Let me give you what my answer would have been before Omicron, and then I can tell you how this new variant probably fits into things. What you have seen since February 2020 at the global level is that the reproduction number for this virus, for all that it’s apparently evolved in ways that have made it more infectious, the reproduction number has gotten pulled down steadily towards one. And what you see with the current wave, before the South Africa stuff hit what we can see is looking around the world, most places, including African countries, were doing quite well in terms of growth really having subsided, that these big waves seem to be ending. So last spring, when Delta emerged in India, we had a global wave that topped out at almost a million cases a day. The current wave, and I don’t know if Omicron will change this, but the current wave seems to have topped out in the mid 500,000 and be on its way back down. And this is at a time of year when we’re more indoors, aerosols behave a bit differently. You would expect the reproduction number to be a little bit seasonally juiced in the Northern hemisphere where this wave is coming from. But it’s nothing like what has come before in terms of these waves.

Part of that is learning, you know, people have figured out how to somewhat have control of this, but part of that is also population immune experience. And I think the figure is something like 53% of the world’s population, you’re talking 4 or 5 billion people, I guess four and change, have had at least one dose of a COVID vaccine. Not all COVID vaccines are created equal, but they pretty much all seem to do something. They pretty much all seem to work, at least somewhat, the vaccines that are in wide use. So you have a lot of immune experience from vaccines. You’ve had less access to them in Africa and Africa looks quite different from the rest of the globe in terms of vaccination coverage. As I say, South Africa in the mid to high 20% coverage is an outlier in the positive sense in Africa, they’re much more vaccinated. Most African countries haven’t got there. They’ve been at the back of the line. People talk about vaccine apartheid. You sure see that with Africa, back of the line and still waiting for vaccine.

But you also have, in addition to that vaccine induced immunity, you have immunity from people coming through infection and surviving. So all of that means that we have a population that really has a lot of immune experience with SARS-CoV-2. And in as much as Omicron is just peppered with mutations, most of the genome, including most of the spike protein, is similar to what came before. So no, I think the important thing is there’s no reason to think this goes back to square one. Can it be a setback? Yeah, it can be a setback. How big of a setback? It’s going to take time to know. But in a sense, these things contain the seeds of their own destruction. If it’s highly, highly infectious, it’s going to mop up residual susceptibility faster. And we’re clearly heading towards the end of this thing. For all a development like this is pretty depressing.

Jordan That’s very comforting to hear. Hopefully the next couple of months are not too difficult. Hopefully we all start taking proper aerosol precautions and wearing proper masks. Dr. Fisman, as always, thank you for explaining this to us.

Dr. Fisman Pleasure. Thank you for having me.

Jordan Dr. David Fisman of the Dalla Lana School of Public Health at the University of Toronto.

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Thanks for listening, I’m Jordan Heath-Rawlings, we’ll talk tomorrow.