What the Numbers Say: Adjusting to a 'New Normal'
On Friday, May 7, CBC Journalist Manjula Selvarajah moderated a panel that tackled audience questions around what it could mean to share a planet with SARS-CoV-2 for the long haul. Evolutionary biologist, Prof. Sally Otto (UBC), infectious disease specialist, Dr. Andrew Morris (Mt. Sinai, University of Toronto), and infectious disease modelling leader, Prof. Jianhong Wu (York University), approached the discussion from their respective areas of expertise, offering a scientific approach to topics such as reopening after lockdown, vaccination safety for children, vaccine passports, and what our "new normal" could look like in the days, weeks, and even years ahead. Below are some highlights of our conversation.
Q: Let’s begin with a general question. From the modelling and the numbers that we have, where are we now?
Prof. Sally Otto: What's very interesting about the numbers is that this isn't about a virus; this is about human reactions to a virus. And so, the modelling requires that we understand both how the virus is spreading from person to person, but then also, how we react, and what our behavioural responses are. And so, we've seen that some people are saying, are we in the first wave, or the second wave, or the third wave? And those are really not the right way to think about it, because we're going to have as many waves as we react to spikes. So, whenever the cases start spiking, we respond. Maybe what's different about the current spike here in Canada is that this is the first time we've seen a spike that's not just due to a change in our behaviour, but due to the appearance of variants of concern. That is, substantially different viruses with enough mutations in them that they're actually causing kind of different disease characteristics.
Prof. Jianhong Wu: I would like to start with a couple of numbers, because I'm a mathematician, and I like numbers. Our first number is a good number: In Ontario, 40% of the entire population has received at least their first dose of a vaccine. We could have better news, but it's a pretty encouraging start. However, we have also experienced the emergence of several variants of concern. They’re called variants of concern because they’re more transmissible than the old virus cycling in and out of the country last year. It has increased by 1.7 to 1.5. What does that mean? It means the 40% vaccination rate is completely offset by the increase in transmissibility of the VOCs. So, where we are now? Right now, we are no better off than we were in December of last year.
The second number I want to show you is the magic number: the reproduction number. It was created by a mathematical modeller who also happened to be a family physician, and this is the number that really tells you, on average, how many additional new infections can be generated by a new infection introduced into the community. At the moment this reproduction number is close to one. When the reproduction number is larger than one, we don't know what's going to happen, and every decision-maker has to make hard decisions. They have to do everything possible to reduce the transmission, otherwise the disease will continue to grow exponentially.
If the reproduction number is less than one, everybody's happy. We can anticipate exponential decline and plan for a reopening. However, this is the most dangerous time. Replication theory says if you double down your effort, you're going to speed up the decline of the disease cases. [This strategy] will buy time for the public health to enhance other public health measures, like contact tracing, isolation, quarantining, and so forth. However, if you relax the restrictive measures prematurely, then it is going to take off again very quickly. You're going to return to the exponential growth.
Q: So, let me ask you this – and I'm sure the audience is thinking about this, too. When will the current wave end? Prof. Wu, can you give us a sense of that?
JW: Sure. We’ve been talking about first wave, second wave, and the current third wave. But strictly speaking, we have not had any “waves”. We started with the opening up process last May, when the first cases declined substantially to a level that we relaxed [public health measures]. So, the first wave never actually ended, it just rebounded. When we reopened, the cases grew and accumulated for a second time to take off to what we called the second wave. That also happened at the beginning of what we called the third wave. So, we actually never ended. It's all a continuation of the same wave.
When you ask when the third wave will end, that's really also dependent on what you mean by the the third wave? Are you talking about the end of the third wave in terms of COVID zero? Or are you talking about the cases going down to double digits or to a single digit? The situation is this: It's predicted that by the end of May, about 65% of the adult population in Ontario will have received their first vaccine dose. So, that's created a good condition for when we talk about relaxed social, the restrictive natures. However, as Dr. Morris just mentioned, there is a lag effect between the epidemic cases and hospitalization and the ICU beds. So, that lag effect will continue to play out and the [reopening] situation will not be possible in the terms of public health capacity until pretty much the end of June. So, we are talking about, potentially we can talk about starting the process of reopening in July.
Q: Dr. Morris, perhaps I'll get you to chime in. You said that getting to that 80% [vaccinated rate] is difficult. Why is that?
Dr. Andrew Morris: If you ask people to eat a healthy diet that includes a fair number of fruits, vegetables and whole grains, it's a challenge. I know it seems like just a hope, but we have a lot of challenges with vaccines – both resistance and hesitancy. They're not the same thing, and it varies across the country. I would actually say that we're doing quite well in Canada. I think we should be very proud, not only of the people rolling up their arms, but also people who have indicated a willingness to roll up their arms. At the moment, it appears that it's only around 15% overall of vaccine hesitancy around the country, which is really fantastic.
But it is a challenge. People have valid concerns. Sometimes it's an issue of communication. There are also challenges in people accessing the vaccines. Some people don't have ready access. Transport mechanisms, language barriers, cultural barriers, and there may be, for a variety of reasons, distrust in the systems or institutions that provide vaccines. All of these things require kid-glove hands to ensure that we deliver vaccines to the people who need them most, will benefit the most, and [also to] everyone else.
What we're going to see over the next while across the country, is a combination of these mass vaccine clinics, and those are going to be dealing with the people who are most mobile and least reluctant to get vaccinations. And on the other hand, we'll have more targeted interventions, hopefully involving a family physician, nurse practitioners, and other primary care providers to make it easier for people to get full, customized explanations. Because what we really want to do is certainly get the most vulnerable of our population immunized, and also numerically, as Dr. Wu just pointed out, as many people as possible immunized.
The last thing I'm going to say to that is, up until just yesterday, that [vaccinated] population was really [just counting] people over age 18. But roughly one-fifth of our population are children or youth. If you don't immunize [our youth], you have to immunize almost 100% of our [adult] population to get us to 80%. So, as we have younger members of our population [now] eligible, it will make it easier to get to 80% immune. Our hope is that most of those people are immunized with vaccines, and not through being infected. We know that vaccinations work better than being infected. The immunity lasts longer. But I think it will be a failure if a large percentage of the population get immunized by natural infection, rather than protected through vaccines.
Q: Vaccines have been distributed to adults. This week, the guidelines were updated to extend vaccinations to children ages 12-plus. There's this whole issue around vaccinating younger children, though. What are your insights on that, especially as it relates to the possible reopening of schools in the fall?
SO: The latest news is that Pfizer released a study and they had no cases in the vaccinated group, and no adverse effects [in the 12-15 age group] other than the typical minor side effects of vaccination. So, that's really good news, and it was showing strong efficacy in that age group. We've already had the first under-15-year-old be vaccinated in Canada, so that was the news this week. A 14-year-old, I believe in Alberta, was vaccinated yesterday.
Here in BC, we don't know exactly what the rollout is for that age group. I suspect it's going to be June-July before we see the 12-18-year-old [cohort] vaccinated, but I think that will come as long as they have enough vaccines to ensure that everybody older than that is vaccinated with their first dose and in time for their second dose.
It does help on many, many fronts. First of all, there's a lot of uncertainty and a lot of fear among children, fear that they may get their grandparents infected, or that they may be spreading it. So, I think it will help allay the fears of youth, that they aren't going to transmit the virus, as well as allowing parents to just be a little bit more assured when their kids are going to school. Kids do transmit less. They're more likely to be asymptomatic, but they definitely do transmit, and they will contribute to that R. So, the more vaccinations we can get, the more we can reduce the growth rate of this disease.
And I should just add on this note that, as Andrew said, roughly on average, 15% of Canadians are hesitant, but if you look at the teenagers and the 20-year-olds, it's almost double that: closer to 30%. And I think that's partly because they think they don't need it, that they personally are unlikely to get sick, so why should they take a vaccine from somebody who needs it? And I think it's really important to emphasize that we're asking everybody to get vaccinated, not just for you, but to provide a halo of protection around those that are vulnerable in your community. So, every person that gets vaccinated is just reduction in that R and risk of transmissions from person to person.
Q: When I've been fully vaccinated, will I be able to meet or hug someone maskless with a person who has also been fully vaccinated?
AM: In Canada, we haven't yet received official guidance about how people will need to behave. The vaccines are a really important part. Immunization is a really important part of public health control of an infection, and the protection that people get isn't just from the vaccine. It's also by making sure that there isn't much circulating virus, because people, even though they're immunized, they may not be 100% protected.
It's sort of like you're wearing a rain jacket that's water-resistant. If it's absolutely pouring outside, you're probably going to get wet over time through it, whereas if it's just sprinkling, you're not going to get wet. And vaccines function in many ways in the same manner, so that if there's tons of virus circulating, and everyone's being exposed to high degrees of virus, you're going to have some degree of infection being transmitted even if you've received both vaccinations.
For example, right now there is a lot of virus circulating [where I work]. I have received both doses, but I wear a mask, and feel the need to wear a mask when I'm indoors, both at the hospital and interacting with people. But if we get our rates down in Canada substantially, I shouldn't need to do that, and I shouldn't need to take any additional measures.
Where that occurs, I think that's going to be a public health decision. I think what I can say fairly comfortably is, that number needs to be pretty low, and the exact numbers, it's probably not that important, but it's got to be much lower than where we are right now.
Q: Drew asks: Pfizer said in early April that people will likely need a booster between 6-12 months from an individual's last dose. My last dose will be at the end of May. Should I be concerned that its efficacy will be greatly diminished come November, especially when that is a time when the rate of infection is likely to go up because everyone's indoors and the virus is seasonal?
SO: We don't have the long-term data yet, but the Pfizer efficacy is fantastic – certainly after two doses – and we have no real reason to believe that it's going to be short-term. I think the concern brought up by Pfizer's representative was that with the variants, so many cases, and so much evolutionary change going on, it may be that there's just too much change happening in the first year so you'll need to get a new booster with the main variants that are of concern.
I know Moderna just released the first data where they altered the RNA to match one of the variants of concern, B.1.351 from South Africa, and they're starting to test it. So, what we'll see coming out in the fall from Pfizer and Moderna are these slightly altered vaccines. And so, we're going to see these kinds of boosters. But whether we need them is still touch and go. We don't yet know if we'll need them.
Q: This is from audience member, Jenny. Are COVID-19 variants expected to mutate on an ongoing basis, or is the situation likely to converge to one or more mutations that would represent peak effectiveness of evolution in a human host? The "Captain America" of [SARS-CoV-2]...
SO: Evolution... you can't stop it. Mutations are a part of life, and thank goodness for mutations. Without mutations, we wouldn't be here. But when it comes to our diseases, we would love to stop evolution. We'd love to stop this virus in its tracks. And we won't. It will always change. Errors always occur whenever anything replicates, including a virus.
Now, so far, we actually haven't seen that many signs of a "Captain America" appearing, which is kind of surprising for a disease that has just entered into humans from an animal host before us. There haven't been a lot of humongous strides in the virus improving to survive in humans. For the whole first year, we really didn't see much going on in terms of evolutionary shifts until these new variants of concern at the end of 2020. So, that's quite interesting.
What will we expect to see with more and more people vaccinated? It's kind of an arms race, where our immune systems are recognizing the old variant. Any mutation that allows the virus to be a little bit better, undetected by our immune systems, that's what's going to be selectively favoured and spread. And we've seen that with other diseases like influenzas, where the virus is constantly evolving. We have either a flu shot or we get the flu and we become immune. So, that's what we'll expect in the long term. I should say, though, that the virus called SARS-CoV-2 usually doesn't mutate as fast as flu. So, we might not even need to get that kind of yearly vaccine boost like we do with the flu.
Q: This is a question from Eduardo. Considering the speed of vaccination around the world, what kind of COVID-19 dynamics could we expect over the next two years at a global level?
JW: Good question, because we are working on some projects related to mass international gatherings, like the Olympics. That is really related to how we can achieve this herd immunity globally to allow for global travel. And it's a very challenging issue, given the vaccine supply. It's a very unfair situation that some of the richest countries, who comprise a small portion of all countries, are taking the vast majority of international vaccine supply. So, achieving the level of vaccination necessary for the global economy to be reconnected again is a huge challenge.
I can anticipate that in certain parts of the world, there would be a sufficient amount of the vaccine available to cover a large portion of the population, but there are countries that you really have to find innovative solutions to combine the limited, growing supply of vaccine, along with other things. I know some of the very innovative approaches, for example, adopted in South Africa, to combine the vaccination along with rapid testing to really identify who has a certain kind of immunity gained from natural infection, and they also combine this with technology to identify the most vulnerable populations, and to also identify the people who are the most active transmitters of the disease.
These kinds of combinations will facilitate a global, integrated approach. Using the vaccine is a major tool, with medical interventions to fight away the COVID-19. So, in the next two years, I feel that the global economy will resume some connections, and global travel will be possible, but I assume either it will be regulated by government agencies or will be forced by industry to require certain kinds of immunization passports for travelers.
MS: Brinja's wondering what conditions may be required before the US-Canadian border could be opened?
JW: I can talk about that a little. The US vaccination rollout has ramped up very quickly, so they might have a better protected population [than Canada]. Actually, we used to be in a better position, so both countries will be in an equal position now to consider whether the border should be re-opened. I think we will not be able to open unless we know that the situation on either side is fully under control, and that we have clear information about the role of [disease] importation. Until that happens, surveillance is not fully established and it will be difficult to prevent a local outbreak if the bigger outbreak is not fully controlled.
MS: What does your use of the word “controlled” mean here? It obviously doesn't mean zero, right? Could we define that a bit more?
JW: First off, we should be able to count our own cases first, so that we fully know the risk of importation. However, our cases are so high that a contact tracing system has not yet been fully established. One thing I really want to emphasize: while we are in lockdown situations, the public health system should be further enhanced. There should be further investment to really enhance the capacity to prepare for reopening, [define] what reopening means, and also [consider the] reopening of the borders. We should have our own surveillance systems to know where the new infections come from, and only then you can identify what are the infections related to the border control. It's a major, important issue.
Q: What do you think the likelihood of a vaccine passport is here in Canada, and is this a good method for keeping us safe or are there some potentially harmful implications?
SO: We've had vaccine passports required for yellow fever in many countries around the world. That's a pretty common requirement. I could see some countries will require evidence of vaccines. We've required evidence of recent rapid testing. It seems similar to that. But I would say more importantly, that's kind of a stick. What are the carrots, and what are the sticks that we're going to use to get that number of vaccinated individuals above 85%? How are we going to get it so that we have enough of a buffer of protection? And the other thing is, while we only have 85% protected, that means we have 15% of Canada that is susceptible still to the ravages of COVID-19.
And so, I think we might see businesses stepping up and saying, look, if you want to come into our restaurant, or into our nightclub, we want to see that you've been vaccinated, just to protect our clients. So, we might see those sorts of encouragements, but I think [with] the vaccine passports, there are some countries where you’ll just need to have that certificate in order to travel [there]. That's an incentive. I do know it's not really the Canadian way to work by sticks on these things, but in West Virginia they're offering $100 if you get vaccinated. I don't know what age group that is, but that's an incentive. That's a carrot.
AM: I think in the short term, oddly enough, the concept is probably easier than in the long term. And the reason is that right now, I think we can feel fairly comfortable that if someone's immunized, then they're protected. What is definitely a foreseeable event to occur sometime down the road is that being “fully” immunized may not actually mean you're protected, and that's the concept of needing boosters. There may be regionalities to that kind of protection. It may be dynamic.
And being able to control that, and then decide when you can say that somebody's protected… what's that period of time from their most recent vaccinations? which is different than most other viral vaccines we've had in the past. If you're vaccinated from Hepatitis B, or Yellow Fever, you're vaccinated. This is a little bit different, and it will potentially add some complexities to it.
Q: Do you think mass implementation of rapid testing would be a viable solution once 50% of the population gets vaccinated, as opposed to a provincial or a national lockdown?
SO: [Because] there's so much uncertainty on exactly where that herd immunity level is, it means we're not going to be able to go and open up everything [at once]. We're going to have to do this in layers, and retain some layers of protection until we get the cases down to zero, or near zero.
I think rapid antigen testing is a really important layer, and I suspect that for two reasons. First of all, COVID has always been associated with a certain fraction of asymptomatic individuals – people that have no symptoms – either because they don't yet have the symptoms, or they never get the symptoms. And [there are also] some of these breakthrough cases, where people who were vaccinated still get COVID. Those seem to have more asymptomatic cases and more individuals that are getting really mild cases. So, in order to detect them, we may need to really increase the use of these rapid testing procedures to catch those people that just feel fine and aren't aware, or have been vaccinated, and still feeling fine, and yet may be carrying the virus and passing it along. Denmark is doing this [rapid testing], I think, weekly. The United Kingdom is allowing anybody who wants a rapid antigen test to get one. And that just allows us to monitor and make sure that we don't have cases running around that we don't know about.
Q: Let's talk about this idea of the 'new normal'. First of all, I think we have to define what we mean by new normal. Prof. Wu, you mentioned that there might be a possibility of a little bit of a breakthrough in July. Is that right?
JW: Right. This will depend on what vaccination is going to look like. We know by the end of May, we're going to have 65% of the entire Ontario population potentially vaccinated for the first dose. Then you take a few months to get a second dose to all the individuals who want a second dose, and that will cure the condition. Starting from July, you can think about a limited lifting of restrictive measures, to potentially sending kids back to school. That would be something we really would be excited about.
I just want to say that you really have to think about this from day one when you're going to remove the stay-at-home order: Planning towards the new normal has to be very carefully done, but the new normal will be pretty much the same everywhere. The real question is how you are going to get to the new normal, and how quickly and how smoothly you can reach that new normal. This is the most difficult part.
MS: So, it sounds to me like you're saying the new normal is the current normal, to some degree.
JW: No. Current normal is what we had in December, remember? But the vaccination rollout is speeding up, so that is creating conditions that are much better than December. And so, you should expect some businesses to re-open with social distancing and limited capacity enforced. And as I said, it's the community's decision [whether] the kids go back to school, and that's the new normal. Also, we may be able to travel with evidence of full immunization, and that's the new normal. My new normal as a scientist is that I don't have to update the situation every day! I may slow down and have room to breathe, to digest information and to analyze information, that I don't have time to do in such a big rush.
MS: So, perhaps we'll get each of you to weigh in on this last question. What is the future going to look like, in terms of public health and pandemic preparedness? Prof. Otto, I'll start with you.
SO: This pandemic has really changed how science is done. It's incredible to see scientists around the world sharing data, looking at data, analyzing it in new and different ways – and we needed that, because we knew nothing to start with about this disease. A lot of science is [now] shared on Twitter, so the role of social media in really quickly getting results out to the public. Rather than those kind of slow journeys to a published paper, we're seeing science posted immediately on bioRxiv and medRxiv. And that's a sea change in how science is done, and I think we're going to see a lot of that stay with us.
One of the things I would really like to urge Canada to do just a bit better is [to] be a bit more open with our data, because we are gaining the benefits of this openness elsewhere, and seeing remarkable studies coming out from the United Kingdom where they have just so much sharing of data that we're getting great pictures about what's happening.
AM: I think the questions started off around the issue of public health, and by my gray hair, you can see I've been around long enough to [witness] SARS. We did have Walkerton in Ontario, with E. coli and H1N1. And we've had a bunch of other public health issues with Lyme disease, West Nile virus, etc. And despite all those things, public health has been massively neglected on a federal level and provincially. There's always a lot of energy right up front and shortly thereafter, and we'll never let this go back to how it was before. But it's a very small percentage of our federal and provincial budgets [that] are put into public health, and all the things that are required to protect the public.
I would love to be proven wrong and say that that's going to change now. I'm very uncertain. It's a neglected area, and there are many scientific fields involved in public health. A lot of the stuff I do with antimicrobial resistance is around that, and up until now it's been neglected. The measure of whether we have learned our lessons or not will be what we do to the structure, and how much is really put in to change the future around this?