WEBVTT - The New Coronavirus Strains 0:00:15.396 --> 0:00:23.796 Pushkin from Pushkin Industries. This is Deep Background, the show 0:00:23.836 --> 0:00:27.436 where we explore the stories behind the stories in the news. 0:00:27.916 --> 0:00:33.156 I'm Noah Feldman. In recent weeks, three new variants on 0:00:33.316 --> 0:00:37.436 COVID nineteen have been occupying a lot of attention in 0:00:37.476 --> 0:00:41.076 the news. There's a variant in the UK that is 0:00:41.076 --> 0:00:45.836 apparently more contagious and possibly more harmful. Then there is 0:00:45.836 --> 0:00:49.556 a variant in South Africa and one in Brazil, at 0:00:49.636 --> 0:00:52.316 least one of which and possibly both of which do 0:00:52.596 --> 0:00:57.396 appear to be less responsive to existing vaccines, or two 0:00:57.676 --> 0:01:02.636 antibodies created by people who've already had COVID. How alarmed 0:01:02.676 --> 0:01:05.956 should we be about these developments, How will they affect 0:01:05.996 --> 0:01:09.396 the interaction between the rollout of the vaccine and the 0:01:09.436 --> 0:01:12.516 progress of the disease, and what will it all mean 0:01:12.676 --> 0:01:15.836 for when we can begin to get back to conditions 0:01:15.876 --> 0:01:20.636 resembling normal. Here to talk us through these challenging questions 0:01:21.116 --> 0:01:25.676 is Mark Lipsitch. Mark now qualifies as a friend of 0:01:25.676 --> 0:01:28.276 a Deep Background for his regular appearances on the show 0:01:28.556 --> 0:01:32.276 to help explain the coronavirus pandemic to us, stretching all 0:01:32.316 --> 0:01:35.516 the way back to February of twenty twenty, when he 0:01:35.596 --> 0:01:38.876 was one of the first epidemiologists to sound the alarm 0:01:39.116 --> 0:01:43.116 about the coming pandemic. Mark is Professor of epidemiology at 0:01:43.116 --> 0:01:46.196 the Harvard chan School of Public Health, and he's also 0:01:46.236 --> 0:01:50.316 the director of the Center for Communicable Disease Dynamics. There, 0:01:50.836 --> 0:01:54.956 he has spent years creating and analyzing models that study 0:01:55.036 --> 0:01:58.516 pathogen spread in a population, and he's also studied how 0:01:58.516 --> 0:02:01.796 to effectively communicate this information to decision makers and the 0:02:01.796 --> 0:02:05.396 wider public. All of that study has turned into practical 0:02:05.476 --> 0:02:08.716 reality over the last eleven months. We're very lucky to 0:02:08.716 --> 0:02:11.796 have back to talk about this mutation and its consequences 0:02:12.156 --> 0:02:14.956 and the lessons we've learned from living with COVID now 0:02:15.196 --> 0:02:21.156 for nearly a year, Mark, welcome back today. I want 0:02:21.156 --> 0:02:24.196 to start with the South African variant, which has been 0:02:24.236 --> 0:02:27.316 getting a lot of attention because of the question of 0:02:27.716 --> 0:02:30.516 the extent to which it is or is not susceptible 0:02:30.556 --> 0:02:34.036 to the vaccines that have been created. So I want 0:02:34.036 --> 0:02:37.236 to begin by asking you, how worried are you about 0:02:37.236 --> 0:02:40.916 the South African variant and what are the consequences of 0:02:40.916 --> 0:02:42.996 that worry for your picture in the big sense of 0:02:42.996 --> 0:02:46.636 where we're headed. Well, I think most observers, including me, 0:02:46.676 --> 0:02:51.876 are seriously worried that this will complicate efforts to protect 0:02:51.876 --> 0:02:55.876 people by vaccination and reduce the quality of immunity from 0:02:55.916 --> 0:03:00.356 natural infection. Because there's evidence that for the South African 0:03:00.436 --> 0:03:04.436 variant that both of those things are likely true, the 0:03:04.836 --> 0:03:10.876 extent of the concern is still really matter ulation. Most 0:03:10.916 --> 0:03:13.516 likely is that there will be some degree of immunity, 0:03:13.956 --> 0:03:18.036 maybe more immunity to severe infection than to getting infected 0:03:18.076 --> 0:03:21.956 at all, but it really remains to be seen. It's 0:03:21.996 --> 0:03:24.956 not a good sign. It will certainly make things harder, 0:03:25.156 --> 0:03:27.596 but I think the degree of that is really a 0:03:27.676 --> 0:03:31.196 matter of complete speculation right now, and is the reason. 0:03:31.236 --> 0:03:35.596 The underlying reason for why both vaccine efficacy might be 0:03:35.636 --> 0:03:38.956 reduced as well as why natural immunity might be reduced 0:03:39.116 --> 0:03:42.956 the same, namely, that the variant has some sort of 0:03:42.996 --> 0:03:46.516 evolutionary shift in the spike protein that makes it less 0:03:46.556 --> 0:03:48.516 of a good match for what's been designed for the 0:03:48.596 --> 0:03:52.436 antibodies created in response to the pre existing version of 0:03:52.476 --> 0:03:56.316 the virus. That's right, So the existing vaccines narrowly target 0:03:56.476 --> 0:04:00.396 a very specific part of the spike protein, but also 0:04:00.956 --> 0:04:04.556 are natural antibodies that we respond that we make in 0:04:04.596 --> 0:04:08.996 response to natural infection. Also, in most people heavily target 0:04:09.156 --> 0:04:12.076 that region of the virus, and so in both cases 0:04:12.556 --> 0:04:16.396 the antibuddies do their job less well. Both Fiser and 0:04:16.556 --> 0:04:22.036 Maderna have released highly preliminary in vitro studies where they 0:04:22.076 --> 0:04:24.156 had a sort of good news bad news formulation in 0:04:24.196 --> 0:04:26.476 their In their pr there the good news was supposed 0:04:26.476 --> 0:04:29.876 to be well. They do say that their vaccines are 0:04:29.876 --> 0:04:32.436 still working on the South African variant, but the bad 0:04:32.476 --> 0:04:35.236 news is that it's not working as well as they 0:04:35.276 --> 0:04:36.676 would have liked it to work. I mean, I'm over 0:04:36.676 --> 0:04:40.436 simplifying that a little bit. And Maderna in fact said, 0:04:40.636 --> 0:04:43.236 just out of an abundance of caution, we're going to 0:04:43.316 --> 0:04:46.276 try to rejigger our version of the vaccine, so we'll 0:04:46.276 --> 0:04:48.436 address the South African varenton. We think we should be 0:04:48.476 --> 0:04:52.476 able to pull that off. Tell me about what should 0:04:52.516 --> 0:04:56.316 one think about those public statements. Yeah, I think those 0:04:56.356 --> 0:04:59.356 are accurate. And of course, where it falls on the 0:04:59.356 --> 0:05:02.436 good news bad news spectrum is the part that I 0:05:02.476 --> 0:05:06.196 said a minute ago is a matter of speculation. I mean, 0:05:06.236 --> 0:05:09.676 this is the general picture. When we have a vaccine 0:05:09.916 --> 0:05:12.196 or we have an immune response, we can measure many 0:05:12.236 --> 0:05:17.556 of its properties, and very often the degree to which 0:05:17.996 --> 0:05:20.516 it works in a test tube or in a cell 0:05:20.596 --> 0:05:25.916 culture correlates with how well it works in people, but 0:05:26.356 --> 0:05:32.236 not usually perfectly, and so translating it's in between nothing 0:05:32.476 --> 0:05:36.636 and very effective into where it is on the spectrum 0:05:36.676 --> 0:05:40.356 of epidemiological effectiveness is the part that we just don't 0:05:40.356 --> 0:05:43.756 know yet but should be able to learn more about 0:05:43.836 --> 0:05:48.276 as we see the variant spread and infect people in 0:05:48.356 --> 0:05:53.236 places with more vaccine coverage. All of this is happening 0:05:53.676 --> 0:05:58.796 in this extremely complicated dynamic game. I mean, for most 0:05:58.796 --> 0:06:00.716 of us who don't do what you do for a living, 0:06:01.076 --> 0:06:04.916 we're just slowly gradually beginning to appreciate just how complicated 0:06:05.196 --> 0:06:07.196 it is to keep track of all the moving parts. 0:06:07.836 --> 0:06:11.716 So we already have this very complicated phenomenon of vaccines 0:06:11.756 --> 0:06:16.876 being introduced, social distancing continuing in some places, and then 0:06:16.916 --> 0:06:19.796 the ongoing spread of the virus. And now, in addition 0:06:19.836 --> 0:06:22.116 to those three factors that were already in play, we 0:06:22.236 --> 0:06:26.476 also have an evolutionary twist that may change the game 0:06:26.636 --> 0:06:28.316 as well. So I want to ask you a few 0:06:28.356 --> 0:06:31.236 questions about the interaction of those four factors. And since 0:06:31.276 --> 0:06:33.636 there's so many moving parts, I'm going to go slowly 0:06:33.756 --> 0:06:36.676 so that you can explain it to me in slower terms. 0:06:38.556 --> 0:06:43.276 Start with which vaccines are in play here? So is 0:06:43.276 --> 0:06:46.676 there a reason to think that, even if Fiser and 0:06:46.716 --> 0:06:51.716 Maderna vaccines work all right on the South African variant, 0:06:51.996 --> 0:06:53.996 that other of the vaccines that are out there in 0:06:54.036 --> 0:06:56.756 the world that are more available, let's say, in less 0:06:56.796 --> 0:06:59.316 developed countries where it's harder to get the refrigeration and 0:06:59.316 --> 0:07:01.436 so forth, is there a reason to think that those 0:07:01.476 --> 0:07:06.236 would be even less efficacious than the mr Anda vaccines. 0:07:08.036 --> 0:07:10.676 I think, first of all, it's not just people who 0:07:10.676 --> 0:07:12.236 don't do this for a living who find it hard 0:07:12.236 --> 0:07:14.156 to keep track of the moving parts. It's really hard 0:07:14.196 --> 0:07:20.076 if you do. In answering your question about the other vaccines, 0:07:20.876 --> 0:07:23.876 a recurring theme in this pandemic, as in a lot 0:07:23.876 --> 0:07:26.436 of science, is there's what we have reason to think 0:07:26.476 --> 0:07:28.796 based on scientific precedent, and then there's what we have 0:07:28.916 --> 0:07:32.756 data about the specifically answers the question. We don't have 0:07:32.836 --> 0:07:36.436 data yet as far as I'm aware, on the effectiveness 0:07:36.476 --> 0:07:40.636 of the other vaccines against this. What we have reason 0:07:40.716 --> 0:07:45.596 to think is that the story will be probably quite similar. 0:07:45.676 --> 0:07:48.156 I think all of the vaccines that are far along 0:07:48.196 --> 0:07:51.556 in clinical trials, and virtually all of the vaccines that 0:07:51.636 --> 0:07:56.236 are being developed, a significant part or all of their 0:07:56.236 --> 0:08:00.156 immune response that they're generating is to the spike into 0:08:00.156 --> 0:08:04.556 this particular these particular parts of spike, and even natural infection, 0:08:04.636 --> 0:08:08.076 which is the whole virus that we can respond to, 0:08:08.836 --> 0:08:14.196 is the response is compromised for the South African variant. 0:08:14.276 --> 0:08:17.556 So I think it would be likely that the story 0:08:17.596 --> 0:08:21.116 will be similar across the board, but there could be 0:08:21.156 --> 0:08:23.996 some variations in the types of immune responses that are 0:08:23.996 --> 0:08:27.396 favored by different vaccines in some subtle way that would 0:08:27.396 --> 0:08:30.956 make it better or worse. Is it right? As I've 0:08:31.116 --> 0:08:34.676 gleaned in a lay person's way, that the mRNA vaccines 0:08:34.756 --> 0:08:38.116 might be more tweakable in the lab and in real 0:08:38.156 --> 0:08:41.276 time than the other vaccines. I mean, that's certainly how again, 0:08:41.316 --> 0:08:44.396 the public relations suggests it to be. Yeah, I think 0:08:44.396 --> 0:08:46.796 the public relations suggests that, and I think it is 0:08:46.916 --> 0:08:52.996 the most straightforward because you're simply generating a sequence of RNA, 0:08:53.476 --> 0:08:56.276 and the sequence can change a little bit, and it's 0:08:56.316 --> 0:08:59.916 those same process as making it the first time was. 0:09:00.556 --> 0:09:05.116 I think a lot of the technologies that are used 0:09:05.116 --> 0:09:08.276 for vaccines have this feature that they take a piece 0:09:08.276 --> 0:09:12.796 of the virus and generate the immune response. So I 0:09:12.836 --> 0:09:16.156 think to a large degree all of the vaccine technologies 0:09:16.156 --> 0:09:19.916 are pretty flexible. I don't know whether mRNA will be 0:09:19.956 --> 0:09:23.916 a whole lot faster. It may be somewhat faster. So 0:09:23.996 --> 0:09:26.636 let's turn then to the first step, as it were, 0:09:26.636 --> 0:09:29.596 of the interaction question. So, even before the South African 0:09:29.676 --> 0:09:33.996 variant was emerging, you've been thinking and writing and speaking 0:09:34.596 --> 0:09:39.836 about the interaction between the rollout of vaccines and the 0:09:39.916 --> 0:09:43.996 question of the trajectory of the pandemic. Would you give us, 0:09:44.156 --> 0:09:49.396 let's say, your prevariant analysis in a nutshell of what 0:09:49.436 --> 0:09:52.116 that interaction looks like, and then we can layer in 0:09:52.156 --> 0:09:55.596 the variant change. If we put aside the variance for 0:09:55.836 --> 0:09:59.196 the moment, then it's clear that for most of the 0:09:59.236 --> 0:10:02.396 world the vaccine is still not a serious factor. For 0:10:02.516 --> 0:10:06.156 the rich countries it is becoming a serious factor, and 0:10:06.396 --> 0:10:10.316 sort of low single digits of percents of people. But 0:10:10.436 --> 0:10:14.596 in most of the developed world it's still a minor factor, 0:10:14.676 --> 0:10:18.196 but is ramping up and the level of coverage is 0:10:18.236 --> 0:10:23.916 likely to be meaningful in a few months well in 0:10:24.356 --> 0:10:27.756 certain rich countries. So you think sort of April May 0:10:27.756 --> 0:10:31.516 and rich countries, it will be meaningful by April May, 0:10:31.636 --> 0:10:36.196 but not necessarily high. I mean, the Biden administration came 0:10:36.236 --> 0:10:38.956 into office saying one hundred million doses in one hundred days. 0:10:39.516 --> 0:10:44.236 The pace has been nearly a million doses a day already, 0:10:44.316 --> 0:10:49.516 and it's been quite quiet from the Biden administration when 0:10:49.516 --> 0:10:52.676 that was reported that this was just a modest increase. 0:10:53.396 --> 0:10:55.116 There was not a statement, Okay, we're going to make 0:10:55.116 --> 0:10:58.076 a two hundred million And I think I don't have 0:10:58.236 --> 0:11:02.516 any particular information, but my sense is there just aren't 0:11:02.556 --> 0:11:05.996 the capacities in the companies to make more doses than 0:11:06.036 --> 0:11:09.076 they're making. And it's not just a matter of saying 0:11:09.316 --> 0:11:11.916 please do it or you must do it. It's just 0:11:11.956 --> 0:11:15.956 that they are at capacity for manufacturing. And one hundred 0:11:15.956 --> 0:11:19.796 million doses means fifty million people vaccinated in a country 0:11:19.836 --> 0:11:25.676 of over three hundreds, so that is still modest prior 0:11:25.716 --> 0:11:28.756 to the variants, and even still, I was saying, I 0:11:28.756 --> 0:11:30.956 don't know when we're going to get to hurt immunity, 0:11:30.996 --> 0:11:33.396 if at all, because we don't know how well the 0:11:33.476 --> 0:11:38.156 vaccines protect against transmission. But at least we can protect 0:11:38.996 --> 0:11:41.556 the most vulnerable people if we can identify them and 0:11:41.596 --> 0:11:46.116 persuade them to be vaccinated. A few tens of millions 0:11:46.116 --> 0:11:49.076 of doses will not quite cover that, but will be 0:11:49.156 --> 0:11:51.636 a very big step towards covering the most vulnerable if 0:11:51.676 --> 0:11:55.196 they're prioritized. Sensibly, can I go back and ask you 0:11:55.196 --> 0:11:57.156 a question about something you just said? Mark, You were 0:11:57.196 --> 0:11:59.956 making the point that we don't know when we'll hit 0:12:00.036 --> 0:12:03.956 hurt immunity with vaccines because we don't know how well 0:12:03.996 --> 0:12:07.036 the vaccines do against transmission. So I guess my first 0:12:07.116 --> 0:12:08.636 question is why don't we know that? It's not just 0:12:08.676 --> 0:12:11.516 a function of the design study that was used in 0:12:11.516 --> 0:12:16.316 testing these vaccines. Yeah, the easiest way to find out 0:12:16.316 --> 0:12:19.756 if someone has gotten the virus is to wait for 0:12:19.756 --> 0:12:22.196 people to get sick from the potentially from the virus, 0:12:22.196 --> 0:12:24.876 and then test them. And so that was the centerpiece 0:12:24.916 --> 0:12:26.956 of the design of all the clinical trials, which for 0:12:27.076 --> 0:12:30.956 very good reasons, were designed to be fast and not 0:12:31.076 --> 0:12:34.516 answer every question, but answer the most important question as 0:12:34.556 --> 0:12:39.996 quickly as possible. Two of the three major vaccine Western vaccines, 0:12:40.756 --> 0:12:44.956 the Maderna one and the astrosenica one, had aspects of 0:12:44.996 --> 0:12:47.156 the trial that gave us a bit of a hint 0:12:47.236 --> 0:12:51.116 about transmission. The Astrosenica trial looked at people in the 0:12:51.236 --> 0:12:54.556 UK part of the trial who were not sick and 0:12:54.636 --> 0:12:56.596 asked them to come in any way and get swabbed 0:12:57.356 --> 0:13:00.716 so they could compare vaccine to posebo and the Maderna 0:13:00.756 --> 0:13:04.836 trial when they had people come in for their second shot, 0:13:05.476 --> 0:13:08.436 swabbed their noses and so we're able to estimate the 0:13:08.436 --> 0:13:11.916 impact of the shot on whether you get infected, even 0:13:11.956 --> 0:13:15.876 if you weren't sick. So each of those gave some data, 0:13:16.276 --> 0:13:18.316 not very much data, but a little bit of data 0:13:18.436 --> 0:13:21.116 that suggests that both of those vaccines do have some 0:13:21.196 --> 0:13:25.236 impact on transmission, which is really good. Question is how much, 0:13:25.476 --> 0:13:27.796 And that's the part where we just don't have enough 0:13:27.996 --> 0:13:31.316 data or enough high quality data to really say. In 0:13:31.476 --> 0:13:33.716 light of that, and again leaving out the variance, which 0:13:33.716 --> 0:13:37.116 will come back to in a moment, do you read 0:13:37.196 --> 0:13:41.836 the situation presently as in the rich countries we're headed 0:13:41.836 --> 0:13:44.836 for a kind of endemic pandemic that never goes away 0:13:45.396 --> 0:13:48.236 fully and is more like the flu, or do you 0:13:48.316 --> 0:13:51.476 read it as again leaving out for a moment the 0:13:51.556 --> 0:13:54.996 variance as something where at least in the rich countries 0:13:55.556 --> 0:13:57.836 eventually maybe it's not going to be in April or May, 0:13:57.876 --> 0:13:59.836 but maybe it's in June or July and August, or 0:13:59.836 --> 0:14:03.276 when more doses become available in a higher percentage of 0:14:03.316 --> 0:14:06.716 the population has been vaccinated, where we might actually be 0:14:06.756 --> 0:14:10.636 able to say COVID is not really a danger in 0:14:10.716 --> 0:14:15.956 these rich countries anymore. I think that would be quite 0:14:15.996 --> 0:14:18.956 surprising to get to the point where we have essentially 0:14:18.956 --> 0:14:21.916 no transmission. I think it's not out of the realm 0:14:21.916 --> 0:14:25.876 of possibility, but I think other scenarios are more likely. 0:14:25.916 --> 0:14:28.636 There was a paper in Science by a group from 0:14:28.676 --> 0:14:32.716 Memory that suggested that it would over time evolve into 0:14:32.996 --> 0:14:36.356 a situation more like a common cold, maybe up to 0:14:36.396 --> 0:14:40.796 influence a severity, but not pose the same danger, and 0:14:40.876 --> 0:14:43.476 I do think that that is the most likely. I 0:14:43.476 --> 0:14:47.116 think vaccines will accelerate that insofar as they protect the 0:14:47.156 --> 0:14:50.476 most vulnerable. But I think when a virus is this 0:14:50.596 --> 0:14:56.356 widespread in most of the world, and when the capacity 0:14:56.356 --> 0:15:00.116 to vaccinate heavily will remain limited for several years at 0:15:00.196 --> 0:15:03.556 least at a global scale, that the right things are going. 0:15:04.276 --> 0:15:07.596 And also, given that the first generation of vaccines probably 0:15:07.636 --> 0:15:11.556 are not super effective against transmission, they probably are quite 0:15:11.596 --> 0:15:14.556 effective if I had to bet on a number, I 0:15:14.596 --> 0:15:17.716 would say they probably reduce it by about two thirds, 0:15:17.756 --> 0:15:21.436 but I could be off maybe maybe eighty percent, which 0:15:21.476 --> 0:15:24.876 would be a lot, but would not be enough to 0:15:24.916 --> 0:15:28.356 get rid of the virus from circulation. And in those numbers, 0:15:28.396 --> 0:15:31.796 even with a very high percentage of the population vaccinated, 0:15:31.836 --> 0:15:35.276 you think there would still be enough transmission going on 0:15:36.156 --> 0:15:39.276 that we're looking at something that fits that that paper 0:15:39.316 --> 0:15:42.996 you were talking about, something more like the common cold. Yeah, 0:15:43.036 --> 0:15:47.596 I mean eighty percent effectiveness and one hundred percent coverage 0:15:47.916 --> 0:15:51.836 might just eliminate it, or nearly eliminate it, but but 0:15:51.996 --> 0:15:56.076 maybe not in all the most densely populated places, which 0:15:56.116 --> 0:16:00.276 could then recede other places. And maybe not. Maybe it 0:16:00.316 --> 0:16:02.996 won't be eighty percent effective, and probably there won't be 0:16:03.036 --> 0:16:07.716 total coverage because everywhere it's been tried so far, there's 0:16:07.756 --> 0:16:12.356 significant vaccine has been so that combination of things makes 0:16:12.396 --> 0:16:15.876 me think a lot of uncertainties would have to go 0:16:15.956 --> 0:16:23.076 our way for elimination to be a realistic possibility. Presumably, 0:16:23.476 --> 0:16:26.756 it's also the case that even in this best case scenario, 0:16:26.836 --> 0:16:29.916 the very small probability one that you're describing, it would 0:16:29.996 --> 0:16:33.236 take years because it would require something like a global 0:16:33.276 --> 0:16:36.556 spread of the vaccine unless you had isolation of the 0:16:36.716 --> 0:16:39.956 rich countries, and you're probably not going to get total 0:16:39.996 --> 0:16:42.556 isolation of those countries. It is not realistic, right right, 0:16:42.596 --> 0:16:46.476 And it wouldn't be justifiable, even for someone like me 0:16:46.556 --> 0:16:49.916 who's been an advocate of control measures for a long time. 0:16:49.996 --> 0:16:53.956 Once we have high vaccination coverage in the most vulnerable groups, 0:16:54.596 --> 0:16:58.036 it would not be economically or otherwise justifiable to say 0:16:58.596 --> 0:17:02.596 we're going to try to keep the economy hobbled for 0:17:02.716 --> 0:17:07.476 months or years just to stop this one virus. I'm 0:17:07.476 --> 0:17:09.516 glad you brought up the control measures because that was 0:17:09.516 --> 0:17:13.236 going to be my next question. Again, once more with 0:17:13.316 --> 0:17:16.316 the caveat of that we don't know enough yet about 0:17:16.356 --> 0:17:20.316 the variants, but again, assuming the variants are relatively controllable 0:17:21.116 --> 0:17:24.476 using the vaccine, where do you think is the right 0:17:24.516 --> 0:17:28.516 inflection point on the control measures? Where in the inflection point, 0:17:28.556 --> 0:17:31.476 what percentage of people need to be vaccinated in a 0:17:31.516 --> 0:17:35.236 country or a region for control measures to be substantially 0:17:35.396 --> 0:17:40.396 pulled back. Well, I think, that's of course a very 0:17:40.396 --> 0:17:44.396 hard question. I think that the first indicator that I'd 0:17:44.436 --> 0:17:49.156 be looking to, or indicators would be in places with 0:17:49.316 --> 0:17:54.756 high vaccine coverage, is there a substantial drop in the 0:17:54.796 --> 0:18:01.316 mortality rate and in the hospitalization or hospital capacity use, 0:18:01.876 --> 0:18:05.356 because those are the two things that are most damaging 0:18:05.396 --> 0:18:08.916 about this virus. It kills people, and it overwhelms healthcare 0:18:09.436 --> 0:18:13.396 indirectly harms people's health. It's going to be hard but 0:18:13.596 --> 0:18:18.196 necessary for us as epidemiologists to try to disentangle how 0:18:18.276 --> 0:18:21.236 much of that is directly protecting the most vulnerable, how 0:18:21.276 --> 0:18:24.716 much of that is reducing transmission through the vaccine, and 0:18:24.716 --> 0:18:27.276 how much of that is reducing transmission through control measures. 0:18:27.756 --> 0:18:32.156 And we'll all be working hard at that, and it 0:18:32.236 --> 0:18:34.956 will be a challenging thing to separate out. But I 0:18:34.996 --> 0:18:41.716 think the scenario that I imagine unfolding and I hope 0:18:41.836 --> 0:18:45.876 is correct, is that as vaccine gets rolled out to 0:18:45.916 --> 0:18:50.196 the people over sixty five and over seventy five, people 0:18:50.196 --> 0:18:53.236 on nursing homes, and people in other of the highest 0:18:53.276 --> 0:18:58.476 risk groups, you'll see still a lot of cases, but 0:18:58.596 --> 0:19:02.476 not nearly so much damage from those cases. You'll have 0:19:02.516 --> 0:19:06.556 a lot of continuing diagnoses, but a dropping ratio of 0:19:07.036 --> 0:19:11.316 hospitalizations and deaths cases. And that would be a sign 0:19:11.356 --> 0:19:14.196 to me that we're doing what we are trying to 0:19:14.236 --> 0:19:17.716 do that, which is to defang the virus by protecting 0:19:17.716 --> 0:19:21.156 the people whom it is most likely to harm. Exactly 0:19:21.156 --> 0:19:24.596 where you then draw the line. You know, it's very 0:19:24.636 --> 0:19:27.196 hard to say, well, we can tolerate this many deaths, 0:19:27.196 --> 0:19:30.196 but we can't tolerate that many deaths. But we tolerate 0:19:30.196 --> 0:19:32.476 deaths from influenza, and we tolerate deaths from a lot 0:19:32.516 --> 0:19:35.676 of other infections. And at some point we will draw 0:19:35.756 --> 0:19:48.836 that line. We'll be back in a moment. Mark, I 0:19:48.836 --> 0:19:51.516 want to ask you a kind of big picture what 0:19:51.596 --> 0:19:55.516 will the world look like question? And let's fast forward 0:19:55.596 --> 0:20:00.156 to September twenty twenty one, when at least in the 0:20:00.236 --> 0:20:04.516 United States, Canada, maybe Mexico, schools are supposed to be 0:20:04.556 --> 0:20:10.236 back in session. And again, let's assume relatively good uptake 0:20:10.276 --> 0:20:14.436 of the vaccine and relatively good efficacy of the vaccine, 0:20:14.876 --> 0:20:18.916 not against transmission but against serious illness. First of all, 0:20:18.956 --> 0:20:21.476 do people go back to school? Our schools open pretty 0:20:21.556 --> 0:20:26.276 much everywhere. And second of all, what does ordinary life 0:20:26.916 --> 0:20:31.516 look like with respect to different control measures ranging from 0:20:31.596 --> 0:20:37.596 masks to social distancing, to closings or openings of retail 0:20:37.636 --> 0:20:45.476 and restaurants. It's just having this exact conversation with people 0:20:46.076 --> 0:20:49.116 at our common University to try to think through all 0:20:49.156 --> 0:20:53.836 of these contingencies. I think under that relatively optimistic scenario 0:20:53.996 --> 0:20:58.236 of high vaccine uptake, particularly among teachers, would be an 0:20:58.236 --> 0:21:06.756 important qualification there for the reopening of schools and continued 0:21:06.996 --> 0:21:11.556 high vaccine efficacy at least again severe disease. I think 0:21:11.996 --> 0:21:15.276 the amount of damage done by the closing those schools 0:21:15.796 --> 0:21:19.516 to kids education is going to be something people won't 0:21:19.516 --> 0:21:22.676 continue to tolerate, and that there will be very very 0:21:22.756 --> 0:21:27.036 much social pressure, societal pressure to reopen schools, and that 0:21:27.156 --> 0:21:32.556 if teachers have access to vaccination in a fairly universal way, 0:21:32.676 --> 0:21:36.436 that will be the likely outcome. For the same reasons, 0:21:36.476 --> 0:21:39.636 I think other things will start to open up under 0:21:39.676 --> 0:21:42.556 such a scenario. And I think if we really have 0:21:43.116 --> 0:21:45.476 if we go a million doses a day for that 0:21:45.556 --> 0:21:48.076 amount of time, all the way through September, we're still 0:21:48.076 --> 0:21:51.516 going to have very low overall vaccine coverage. But if 0:21:51.596 --> 0:21:54.956 other vaccines come on and are highly effective, and or 0:21:54.996 --> 0:21:58.996 if we get more manufacturing capacity for the existing vaccines, 0:21:59.596 --> 0:22:03.636 then we will start to have some reasonable level of 0:22:03.676 --> 0:22:07.156 coverage and the population and with it, I would expect 0:22:07.276 --> 0:22:12.556 some reduction and transmission. I think the one caveat to 0:22:12.676 --> 0:22:17.796 that is that the seasonal changes that we saw last 0:22:17.796 --> 0:22:21.236 summer will probably happen again this summer, So everything will 0:22:21.236 --> 0:22:23.596 look better in the summer as it did last summer, 0:22:23.716 --> 0:22:27.396 because people will be outside more, the virus will transmit 0:22:27.476 --> 0:22:31.516 less well, and we may have a sense of security 0:22:31.516 --> 0:22:34.116 as we did last summer. That's partially due to the 0:22:34.196 --> 0:22:37.636 vaccine and partially due to seasonal factors, and so I 0:22:37.636 --> 0:22:41.276 think we're going to have to try to again separate 0:22:41.316 --> 0:22:46.676 out that contribution and make sure that as things reopen, 0:22:46.716 --> 0:22:48.956 which there will be great pressure to do, and we're 0:22:48.956 --> 0:22:52.276 not setting up for another bad winter like the one 0:22:52.316 --> 0:22:54.916 we've had here. But I think if we continue with 0:22:55.076 --> 0:22:59.196 continued high coverage and continued high efficacy in the most 0:22:59.236 --> 0:23:01.916 at risk groups, it should be a very different winter 0:23:02.036 --> 0:23:07.996 next year. You mentioned vaccinating teachers before us potential fall reopening. 0:23:08.156 --> 0:23:10.596 I know that in the debate about whether teachers should 0:23:10.636 --> 0:23:13.076 come first, or whether professions should really be our basis 0:23:13.756 --> 0:23:17.236 for vaccination as opposed to the people most vulnerable and 0:23:17.276 --> 0:23:20.316 most at risk, you have been more unvaccinate the vulnerable 0:23:20.876 --> 0:23:24.836 rather than identify a professional class like teachers. But it 0:23:24.876 --> 0:23:27.476 sounds like maybe as we get more vaccine out to 0:23:27.516 --> 0:23:29.996 the population, you think it would make sense to target 0:23:30.036 --> 0:23:33.036 teachers in order to achieve the social goal of reopening schools, 0:23:33.116 --> 0:23:35.316 or at least an acknowledgement of the fact that people 0:23:35.316 --> 0:23:37.356 are going to want it anyway. I have been very 0:23:37.436 --> 0:23:41.556 much in favor of trying to vaccinate first those who 0:23:41.636 --> 0:23:44.596 would be most likely to die. I do think that 0:23:45.756 --> 0:23:49.836 of all the professions, apart from healthcare workers, teachers play 0:23:49.996 --> 0:23:53.916 a truly fundamental role in our society for a whole 0:23:54.076 --> 0:23:57.156 variety of complicated reasons. But one of them is that they, 0:23:57.796 --> 0:24:01.036 through their childcare role, they make it possible for other 0:24:01.076 --> 0:24:03.876 adults to work. And another one, which we think of 0:24:03.916 --> 0:24:07.996 as the primary one, and it is, but it's not 0:24:08.076 --> 0:24:11.836 the only one, is that they create human capital and 0:24:11.876 --> 0:24:15.836 they and they educate our children to move on with 0:24:15.956 --> 0:24:19.796 their lives. And those are two really, really fundamental roles 0:24:19.836 --> 0:24:24.596 that are different from those of many other important occupations. 0:24:24.756 --> 0:24:31.316 And I think there will be appropriate demand to vaccinate 0:24:31.356 --> 0:24:35.676 teachers at least in time for fall reopening, which in 0:24:35.716 --> 0:24:40.956 practice means starting probably in the late spring. Mark you 0:24:41.076 --> 0:24:47.716 describe that scenario, that September scenario as optimistic. I grant 0:24:47.716 --> 0:24:50.996 you that it's optimistic. How optimistic I mean, does it 0:24:50.996 --> 0:24:54.036 seem to you when you really check your gut pretty 0:24:54.116 --> 0:24:58.556 darn unlikely that by September again in the United States 0:24:58.556 --> 0:25:02.716 will have enough vaccine uptake, declining mortality among the most vulnerable, 0:25:02.756 --> 0:25:04.836 and be able to begin the process of really getting 0:25:04.836 --> 0:25:07.676 back to normal. Or when you think in singularly, you say, yeah, 0:25:07.716 --> 0:25:09.756 that could be, but we have to be honest. Things 0:25:09.756 --> 0:25:11.836 are more things, things are changing, and it might will 0:25:11.836 --> 0:25:13.396 come out of different ways, so we should be prepared 0:25:13.396 --> 0:25:17.916 for something different. I think if I had to put 0:25:17.996 --> 0:25:21.756 my that's on the most probable scenario, it would be 0:25:21.876 --> 0:25:26.076 of a September that we would all be reasonably happy 0:25:26.116 --> 0:25:29.596 with in terms of our lives being something like what 0:25:29.716 --> 0:25:32.396