You’re listening to a press conference from the Harvard T.H. Chan School of Public Health with Marc Lipsitch, professor of epidemiology and director of the Center for Communicable Disease Dynamics. This call was recorded at 11 a.m. Eastern time on Wednesday, July 1st.
MODERATOR: Dr. Lipsitch, do you have any opening comments?
MARC LIPSITCH: Sure. Thanks, everyone, for joining. I look forward to talking about whatever is on people’s minds. I think there’s a fair amount of news today. Everyone’s aware Tony Fauci described the possibility of a hundred thousand new cases per day as a potential future for our country. And I’m afraid that seems reasonably likely to me on current trajectories. Also this morning, a group of institutions, including the Rockefeller Foundation and the Safra Center at Harvard and Harvard Global Health Institute and others, released what I think is a very useful set of guidelines for cities and other jurisdictions to understand what’s needed for control and for contact tracing and other aspects of control.
I’ve put the link in the chat.
I have perhaps a slightly different and less-optimistic perspective about contact tracing than that report. But on the other hand, if you read that report carefully, it suggests that the intensity and success of the metrics that the effort would need to meet are rather stringent. And so if indeed a contact tracing effort could meet those those metrics, then I think it would really be quite different from what’s seemed possible so far in the United States. So, happy to talk about that further. And then another topic that I would be happy to discuss, I thinkthis question of how vaccines are going to be distributed if and when they’re available around the world is one that has been worrying me. And I don’t have a lot of solutions, but I think that’s a topic that probably needs more coverage.
So, I’ll stop with those very general comments and start taking questions.
MODERATOR: Thank you, Dr. Lipsitch. All right. First question.
Q: Hi, thanks for doing this. With the Fourth of July this weekend, I just wanted to ask, are you concerned that we will see a surge in cases linked to the holiday, like we saw after Memorial Day weekend?
MARC LIPSITCH: I think it’s possible. I think as with any single point in time, it’s difficult to attribute a surge to one activity. And I imagine that a lot of the activities over the holiday will be out of doors, which, as we’re increasingly beginning to find, is a safer place to do almost everything.
But, yes, I think I think there’s both a continuing trend of reopening, although being tempered in a few places, and that the holiday itself will bring more people together and probably add to transmission, particularly given that we have really active epidemics going on in so many states.
MODERATOR: Next question.
Q: Hello, Doctor. My question is regarding the virus mutation possibility in the winter and whether we may have a new strain more deadly in the coming few months.
MARC LIPSITCH: Sure. So I think we have to make some distinctions here. And I’d refer you to a blog post that my colleagues at the Center for Communicable Disease Dynamics put up. I’ll try to put that in the chat if I can, after I finish answering about mutation and what it means. So the virus is mutating. All viruses, and especially RNA viruses, mutate.
That means genetic change, but it doesn’t necessarily mean a change in its properties biologically. So we can observe it, but it doesn’t necessarily mean something good or bad for us. There is always the possibility of a virus having a mutation that changes its biological properties. And then whether that becomes more common or just becomes a dead end and that strain tends to not take off, that depends on whether it gets into a population that’s doing a lot of transmitting. So it depends on the luck of that strain. And it also depends on the fitness of that strain, meaning whether that change is making it transmit more effectively and more efficiently. And people sometimes equate being more deadly with being more transmissible, but that’s not always true. It can be true, but it can be the opposite or it can be unrelated. So I think we have a big problem now.
We need to be monitoring and considering plans for a worse strain. But I think at least in many parts of the world, we’re doing a sufficiently bad job of dealing with the strain that we have now that that our focus should be on that at the moment. Sometimes people draw parallels to the 1918 influenza, which was milder in the first wave in the spring of 1918 and seemed to be more deadly in the fall and winter. Whether that was a change in the virus or whether that was a change in the populations it was infecting or other things that were happening, like other secondary infections, nobody has really nailed down. And that’s one of the great mysteries of epidemiology history that we would all like to solve someday. But that precedent is in people’s minds, it’s an important thing to keep in mind, but I think at the moment, we have a really big problem, and we need to deal with that problem.
And the expression “dead viruses don’t mutate” is an important one. The less virus we have in the world, the fewer cases we have, the better the chance that it stays similar to what it was, rather than getting more severe. So, controlling this virus is really where our priorities should be.
Q: Is there a certain mechanism or protocol we can expect in distributing the vaccine and who can get it first, as it’s the main issue in the world now?
MARC LIPSITCH: Sorry. I’m not sure what’s the question.
Q:Yeah. I’m talking about if there is any mechanism or protocol we can expect in distributing any prospect or vaccine, and who can get it first?
MARC LIPSITCH: Yeah. So I think there is very hard work going on with the coalition of the World Health Organization and GAVI, the Global Alliance for Vaccines and Immunizations, and CEPI, the Coalition for Epidemic Preparedness Innovations.
The three of them are working very hard together to design mechanisms by which vaccines would be available in a fair and equitable way across the world. Counter to that, I fear, is that individual governments are worrying about or are trying to find ways that they can increase their own access at the expense of the world.
And I think this is potentially a major source of geopolitical tension, if, in fact, there is a vaccine that is available in limited supply and the powerful countries and or the countries that develop it find ways to sequester much of that supply. So I think that’s an issue that’s not receiving enough attention. I don’t know that there is a clear solution.
But we need to be at least aware of it and try to find ways to address it, because I don’t think it’s being fully addressed at the moment.
MODERATOR:Thank you. Next question.
Q:Thanks, Professor, for taking the time. So Dr. Fauci said there’ll be a hundred thousand cases a day, potentially. What will America be…
MARC LIPSITCH: Sorry, you faded out.
Q: When that happens, will there be overloaded hospitals, people dying, and will that overload our health system and create a [inaudible] scenario? Could you hear that?
MARC LIPSITCH: Sort of. But since you e-mailed me earlier, I know you know roughly what you’re asking.Yeah.
So I think that the most likely scenario for that is that it will be quite variable regionally and that we won’t necessarily see every place struggling, but we will see some places struggling.
And that would, and it seems most likely to me that there will be parts of the country where the health care system will be overwhelmed with that kind of level, certainly. You know, if parts of Texas went to two and a half times their current caseload, that would be disastrous, because the current is about forty thousand cases a day, I think, in the US.
So there will be some places that will really struggle. And my guess is that those will be different from the ones that struggled the first time because people seem to learn lessons very locally.
And I think at least some of the jurisdictions that were hardest hit in the first round are being much more cautious at this point. But that would, I think, lead to widespread school closures, if they’ve been open. I think it would it would be a more generalized version of what New York City was experiencing a few months ago.
MODERATOR: Do you have a follow up?
Q: Just, when you say a more generalized experience, do you mean, you know, a wider spread, a bigger scale disaster than New York?
MARC LIPSITCH: I mean, geographically more widespread.
Q:Thank you very much.
MARC LIPSITCH: I put in the chat the link to the blog post on mutation from our center, and also before that I put an op-ed that I thought was really well written by Helen Jenkins from Boston University and Bill Hanage from our center. They are married to each other. And there was in the Washington Post this morning about the sort of tradeoffs around if we want to reopen schools, what needs to be done in the meanwhile.
MODERATOR: Thank you. Next question.
Q: Thank you, Dr. Lipsitch. I have a question. I have two questions, actually. If we look at the statistics, the numbers of cases in some places are going up and at the same time, the deaths numbers are going down. So what can that mean? Can that mean that the virus is getting weaker or it’s just, I don’t know. Can you explain why is that?
MARC LIPSITCH: Yeah, thanks for that question. I think there’s really no evidence that the that the virus itself is changing in a biologically meaningful way. There have been some false alarms about that. It’s not that it’s impossible. We still need to monitor for that. But the evidence of that is, in my opinion, so far non-existent. We’ve understood for a while that deaths are a trailing indicator of cases. And that’s because it takes a long time for people to die relative to when they got infected.
And if you look at states like Georgia or Texas, the big increases in cases started about two weeks ago. And the sort of rule of thumb for cases to deaths is probably three weeks, depending on how long it takes to confirm cases. So it’s maybe three to four weeks from infection to death among those who die, and confirmation of the case is somewhere along that trajectory. So if that’s the case, then we would expect to see increases starting in about a week or so.
But I think the other thing to say is that this is such a localized epidemic that when you have different curves on top of each other and we just add them together, you can get periods where curves are out of sync. So if deaths still haven’t increased in a couple of weeks, then we will really have to try to understand what’s going on. But I think at least for some of the main states that are really going up fast in terms of cases, it’s a bit early. The other thing to say is it it may well be, and I don’t have any data—this would be a useful thing to try to work out—it may well be that as health care professionals are learning how to treat this illness better, that a smaller proportion are dying. I haven’t seen the evidence of that. But I think that’s a serious hypothesis that needs to be tested.
Q: And another question is about Dr. Fauci’s testimony in the Congress. So what could be the outcome of that testimony, because he did mention the possibility or necessity of a second lockdown. Do you see that in the future in America?
MARC LIPSITCH: I think I think it at the rate things are going, it’s going to be necessary in some places.
I hope not in all places. And I think it is gratifying to live in a state that seems to be both doing things very carefully and slowly to reopen and seems to be doing so successfully in terms of our case numbers and death numbers. So I hope that, for example, Massachusetts is not a place where that will happen. But I think when a city or a state experiences a really intense surge, unfortunately, it may take that before controls are reimposed. It would be much more efficient to reimpose those controls.
Perhaps not as intensely right now, but that’s not happening on a large scale.
Q: I’m going to ask one more question about just America is leading in the cases comparing to other countries. I know that, you know, Russia is probably not giving all the information like China. But why do you think America is the largest economy, one of the best medicine in the world, but still, we’re seeing more cases here.
MARC LIPSITCH: Dr. Michael Ryan from the World Health Organization stated this morning—I think it was this morning in a virtual meeting that I read about on Twitter, at least in the last 24 hours—he stated that countries with strong federal governments or national governments that—let me see if I can get his quote correct.
Something about that, let’s see, countries with governments that communicate complex science directly to the public and use science as the basic control have had much better success in fighting COVID-19.
And I think you can see that borne out both in the comparison of the U.S. as a whole to many other countries, like most of East Asia and most of Europe, that at the federal, national level we have been obfuscating the problem, we obfuscated the problem for a long time. We’ve had inconsistent messaging and sidelining of the scientific parts of the federal government in favor of the politicians speaking non-science and often incorrect information. And I think we’re seeing that, and I think also that within-country comparisons in the U.S. show that the states that have taken this seriously and followed the science while trying to protect the economy—following the science doesn’t mean lock it down and never let up—following the science means communicating clearly and doing those things which are scientifically believed or known to be effective. Those states are doing, on the whole, much better than states that are following the national lead.
Q:Thank you so much.
MODERATOR: Next question.
Q: I was just interested to hear what your concerns are about distribution. If it was what you just said earlier about equity, or if you have others as well.
MARC LIPSITCH: Yeah, I think there’s a real concern about equity and that in addition, it will further fray international relations, which are already, in many cases, quite frayed, if even among countries that are, you know, where there’s not an equity issue, if certain countries try to sequester vaccine doses for their populations. Solutions to that include internationalizing production capacity, and I know that’s one of the strategies that’s being pursued, so that the vaccines are not physically all in one country. This assumes that there’s at least one vaccine, and ideally many vaccines, that are effective. So I think that’s one approach. I think another approach is trying to get countries to buy into a plan before anyone knows which vaccines are effective, so that we’re not, so that in the same way that you buy insurance before you know whether your house has burned down, you buy into a plan for distribution before you know whether you have all the chips or you don’t have all the chips. I think that’s another part of it.
And this is not really my area of expertise, but it’s an area where I’m really concerned because I think vaccines will be a very valuable commodity.
Q:And do you think that, could you play out a little bit what the consequences would be if one country does end up with a lion’s share of vaccines?
MARC LIPSITCH: I mean, again, I think it’s not my area of expertise. I really was suggesting to get it on your collective radar screens rather than that I have tremendous insight into the details. But I think there’s a lot of opportunity for mischief.
MODERATOR: Thank you. Next question.
Q: Hi, thanks for doing this. I wanted to follow up on schools. I saw the op-ed you mentioned as well. But I guess, you know, a lot of people are saying, well, schools depend on how bad the virus is in that area. I wonder if you could expand on that. Like, how do you have, say, a medium amount of virus circulating in that area? I mean, should you still have in-person schools, you know, or how bad does the outbreak need to be in an area that we would not want to have in-person schools?
MARC LIPSITCH: I think that’s a good question. Clearly, if the rest of the economy is shut down because of stay-at-home orders, then schools probably should follow that. I think there’s enormous value—and the American Academy of Pediatrics has written about this— there’s enormous amount of value to having schools open, not only for education, but also for medical care, speech and occupational therapy, food distribution. I mean, they really are—unfortunately, what’s left of our social safety net, much of it is tied to schools now. And having them closed is not something anybody should be in favor of.
I think every state is trying to figure out the plans for how to respond to, or how to deal with schools. I think most states are planning to reopen, as best I understand, in August or September, when their normal calendar is. And I think my guess is that there will be a lot of experience, a lot of lessons learned in the first few weeks of that.
I think we still don’t have a large scale sense of what role schools will play in transmission and that we can make rules or principles now. But I think we will end up changing them once we see a little bit what role schools are playing. And I know states, including Massachusetts, are very rapidly trying to develop guidance, but I don’t have a good answer for you right now. I agree very much with general view of the op-ed that my colleagues wrote that schools will be more sustainable in an environment of more limited transmission. And exactly where the cutoff is I can’t tell you at this point.
Q: Got it. Thanks, that helps. That’s good.
MODERATOR: Right, next question. Can you go through the measures that you think the federal government should take now to reverse the current trend?
MARC LIPSITCH: I think that it’s hard to know where to start. In terms of strategy and message, I think that the CDC and the other public health experts within the government need to be on the front lines, talking to the country every day and talking science and what we know and what we don’t, the way they did in 2009 during the flu pandemic, and that people without scientific qualifications obviously have decision-making authority and have lots of role in this, but do not need to be stealing the show in terms of public communication.
So I think that’s the first thing. I think the second thing is that that needs to be sort of unmuzzled. I was delighted to see Anne Schuchat’s name in the news for the first time in a month or so, who was who was the voice of CDC in 2009 for much of the flu pandemic and has been quite absent. So I think maybe there’s some loosening there, I don’t know. In terms of more concrete measures, I think real, consistent messaging about the importance of masks and encouragement of requirements for masks in those places where they aren’t required at the moment.
I think support for really larger, even larger scale testing in order to try to reopen schools. I think that will be an important piece of the reopening. And still the federal role has been a mixed one at best in terms of availability of testing. And I think, also, more federal leadership on all the issues around making it possible for people to survive economically as we have more economic disruptions. And that includes proper policies to let people stay home from work if they’re sick and not suffer economically, which I think is still at best a patchwork in this country, and other economic measures that can be taken.
And then, well, so I think those would be good starting points, and many things will follow from that, from having the public health authorities in a position of leadership.
MODERATOR: Thank you. Next question.
Q: Great. Thank you so much for doing this. I wanted to go back to the messaging point you were discussing earlier and ask what you think specifically the federal government needs to do to sort of help us dig out of the hole we’re in in the Southeast and the Southwest. What should they be saying at this point? What are the crucial messages?
MARC LIPSITCH:I think it’s a lot of what I just said, but also I mean, I think in at least the Southeast, which I’ve been watching a little bit more because I used to live there, the reopening has been rapid and really not very tied to positive, beneficial trends in the epidemic or tied to sort of economic necessity. And so I think the federal government needs to make it clear that if cases get above a certain level, and if the trend is negative, then it’s harmful, you know, is positive in cases, that further retreats from the opening and moving back towards being closed down are going to have to happen. And if the federal government isn’t saying that, and they quite distinctly never said how you would retreat from the reopening, they only suggested a plan for reopening. If the federal government isn’t pushing that, then the people who are politically allied with our president, like the governor of Georgia and the governor of Texas, are going to be even more inclined to just keep the trajectory of reopening. So I think if the federal government isn’t saying clearly we have a common interest in keeping this virus under control, which will help our economy and will help our health and will get us to a point where we can function again, then we can’t expect states—we can hope, but we can’t empirically, we can’t expect states to behave in that way. So we just need federal leadership of the sort that we’re having from states like New York and Massachusetts to say we’re taking this seriously and we’re reopening only when we see continuing beneficial trends.
Q: You mentioned how important it was to put people with scientific qualifications at the forefront of the messaging. Given what we know and how we’ve seen the politicization of things like even masks, does the CDC or Schuchat or Fauci screaming from the rooftops matter if the president every now and then tweets something different?
MARC LIPSITCH: I think if the, I mean, I’m encouraged to see that, for example, Republican senators are now sort of falling in line with the notion of masks and helping to depoliticize that. That’s one of the nicest developments I’ve seen in a while.
I think the president has a unique ability to derail good policy in this country—this president—and you’re right, it could be that that won’t preclude scientific leadership from getting its message through. But at the moment, we don’t know, because they’ve been so sidelined and so absent from the public discussion and so much overshadowed by the president and the vice president dominating the media on this topic. So I think we’ve got to give it a try. And yes, it won’t be as good as if there was presidential support, but it would be better than not having a message out there at all.
Q: Thank you.
MODERATOR: Next question.
Q: Thanks very much for your time. My question is about containment. I’m starting to hear some communities say that they’ve contained the virus. So is there a standard definition of what containment means? Is it positive case rate, or transmission rate, something else?
MARC LIPSITCH: I don’t think there is a standard definition. Which communities are you referring to?
Q: Central Falls, Rhode Island, a couple of real hotspots where they were very densely packed, minority, predominant communities. That would be one of them. And then there are a few in Massachusetts that are making that claim as well.
MARC LIPSITCH: Yeah. I don’t think there’s a technical definition of containment. Yeah. And I guess I’d have to see what they’re referring to understand it better. I hadn’t heard that description.
Q: Well, you hear a lot of politicians and such say, you know, we’re trying to contain the virus. How will we know when that’s the case?
MARC LIPSITCH: Right. Well, I think the broad goal is to bring the daily number of new cases, of true new cases, which we get some picture of from the number of detected new cases on a downward trajectory, and in particular on the downward trajectory to a point where the medical care system is is very much able to deal with them, and the public health system is able to make a significant impact through contact tracing on further reducing those numbers. And I think that one of the merits of the of the new—it’s not totally new, but the newly consensus—recommendations from Safra Center and Harvard Global Health Institute and Rockefeller and others is that they put numbers to that. So they say sort of green zone of things are OK. It is less than one detected case per hundred thousand people per day, which is something I think—I haven’t checked—but I think there’s probably no state that’s at that point. Massachusetts is around two. We have, I think we had a hundred and fourteen cases, if I’m not mistaken, yesterday, in a population of seven million. So it’s about one and a half, almost two per hundred thousand. So that’s not far. But it’s a little bit above. Much of Europe didn’t even begin reopening until they were under two per hundred thousand. And much of and, you know, Korea began reopening when it was at about one per million or one tenth per hundred thousand.
So it’s a bit arbitrary. But I think one per hundred thousand per day is a kind of reasonable estimate of what real containment means.
Q:Thank you very much.
Q: Good morning. I want to shift gears a little bit, if you don’t mind. There’s been some research suggesting aerosols disperse and present less risk outdoors than indoors. But it doesn’t seem like there’s a lot of research specifically on that. It makes obvious sense, but on a, let’s say, a calm, windless day is outdoors spread risk really that much different from indoor, if you assume equal physical distancing and other factors?
MARC LIPSITCH: It’s a good question. I think, I mean, the volume—I don’t know enough physics of outdoor air mixing to give you a good answer, but my feeling is that even though the movement of air may not be so great, the volume of air that you have to disperse into is much greater than in an enclosed room. So I think I think that’s likely to be the case, but it’s the limit of my knowledge.
Q: Quick follow-up, if you don’t mind. Would you would you join friends for dinner at a table outside in a restaurant, if all the other tables are six feet apart?
MARC LIPSITCH: Yes, I have, actually. Once. I don’t think that’s a riskless activity for, you know, for various reasons. But the waitstaff were masked. We were masked when we weren’t eating. And it was out of doors. And in fact, it was with family, and one friend that’s almost family. So, yes, I think at this stage in Massachusetts—this was in western Massachusetts, where there are very, very few cases—that seems completely reasonable to me. If I were in Houston, Texas, I might not.
Q: You answered my last question. Thank you.
MODERATOR: Next question.
Q: Hi, Professor Lipsitch, thank you for the time. Thank you for this interview. I’d like to to ask you: What we are now seeing in the United States, is it actually a second wave erupting in the world from in the summer from the United States, and we might see this spreading across the globe? And also, we learned the other day about the new swine flu in China. Do you worry it might combine with COVID in the next months?
MARC LIPSITCH: I think that there’s always that worry. I mean, there’s always a worry that something more could go wrong. And as I said, with mutation, I sort of think worrying right now, obviously, there needs to be effort to understand and contain that virus if possible. My understanding is so far it has not made very many people sick. So that that’s somewhat encouraging, although not the total answer. But as I said before, with the question of mutation, I think we have a big problem on our hands, and we should focus our resources on solving that problem, while not ignoring the other ones. In terms of what the U.S. is sharing with the rest of the world, my sense is that travel has been reduced so much from the U.S., especially now with new regulations from the E.U. that the U.S. as a source is not going to be that significant to the rest of the world. But we will we will have to see.
Q: So as the virus seems to be persistent, does this imply that borders will remain indefinitely closed and travel restricted for a long time?
MARC LIPSITCH: Well, I think we’re sort of seeing this weakest-link phenomenon that the places that have the virus under control are having to close their borders to the places that don’t. I think, I mean, again, I’m not a political scientist or an international relations expert, but I do think there’s a chance that we will see, sort of, as we’re seeing both at the between-countries level and between-states level, we’re beginning to see sort of groups of countries that say, you know, we all trust each other, but we don’t trust certain other countries to keep the virus under control. And so I think there will be regional coalitions of places that restrict travel from outside that region and permit it within the region. I think that may be sort of beginning to happen in the northeastern United States. At least I’ve seen press reports suggesting that. So it’s a very weird situation with so much geographic heterogeneity.
Q: Right. But you hesitate state to call it a second wave.
MARC LIPSITCH: Yeah, I mean, I think, as I’ve said to others, I think wave is a term that we used a lot during the first wave, or that we used a lot in the past. I’ve tried recently to move away from it, because I think wave gives this impression that it goes up and then it comes down if you do nothing. And that’s not really what happens with viruses, unless you wait long enough so that herd immunity at a high level starts to kick in and then it brings it down. But we’re not near there. So these waves, so-called waves, are not really waves. They’re sort of outbreaks that get quashed or don’t get quashed. And so I think I’m going to try not to use the term wave, but I think a second set of outbreaks in Europe and in other parts of the world, seeded by imports from the U.S. and from Brazil and from other hot spots, is certainly possible. But again, it depends on the amount of control. And the other thing about waves, is it’s, you know, once they start, they’re hard to stop the increasing part. But in fact, we can stop, countries can stop the increase by making sure that the imports are few and that those that are imported are caught quickly.
Q: Right. Thank you, Professor Lipsitch, thank you very much.
MARC LIPSITCH: Sure.
MODERATOR: Next question.
Q: Thank you for taking the question. I’d love to circle back to masks, if you don’t mind. I feel like the plea from public health officials has really increased in the last week or two on the importance of wearing a mask right up there with social distancing and handwashing. So I’m curious, is there anything we’ve learned that’s new when it comes to the effectiveness of face coverings, especially, you know, when worn collectively as a community, what they can really do here?
MARC LIPSITCH: I think there have been some papers suggesting sort of quantitative estimates.I think I’m not aware—you know, it’s a classic problem of you do six interventions at once to varying degrees and try to estimate which ones are important.
And I’m not, I’m sort of one of those people who tends to not put a lot of faith in the precise quantitative estimates, especially at the population level. But to say that it’s a low cost and likely effective approach to reducing transmission. But I haven’t put a lot of stock in the specific estimates the people have put out. So I guess I’ll leave it there.
MODERATOR: Next question. Please go ahead.
Q: So I have a question about how childhood vaccine rates in the country have gone down due to fears of parents bringing in their children to the doctors offices because of coronavirus. I’m wondering if you have any thoughts about this, or what you think about the impact could be?
MARC LIPSITCH: Yeah, I think, I haven’t seen the data, but I’ve heard the general issue raised. I think it, like any other cause of lower vaccination rates, it primes us for outbreaks of the vaccine-preventable diseases. And I think it is a concern. I think primary care physicians and practices need to find some ways to make sure that vaccination coverage is maintained, and if they can’t do it, then public health departments. Certainly during the period of nice weather, you could imagine an outdoor vaccination clinic that was one option. But I haven’t seen what the innovations in that space have been. It just seems like a real need.
Q: Thank you.
MODERATOR: Next question.
Q: Hi. Thanks so much for doing this, Professor Lipsitch. So Governor Ron DeSantis in Florida has largely attributed the growing case numbers here to social behavior on the part of young people. He’s argued while it’s bad that young people are getting infected, it would be worse if the most vulnerable Floridians were to contract the disease, like people staying in long-term-care facilities. So in your view, to what extent is attributing that spread to younger people and arguing that those people are less likely to get the symptoms a sustainable virus-containment approach?
MARC LIPSITCH: I think it’s clear that when it spreads in one group, it spreads in many groups. I mean, even in places that were really trying to reduce spread in all groups, like New York City at the height of its epidemic, once it got into, it very effectively got into long-term-care facilities. And Massachusetts had a similar experience. Not as bad as New York, I think.
So, I mean, on one hand, it just doesn’t make sense to say we’ll just keep it out of the nursing homes, because even with more limited transmission in the rest of the population, that doesn’t seem to happen. On the other hand, that presents a real dilemma, because we haven’t found a really good way to protect the elderly, and especially the institutionalized elderly. Even when measures outside those contexts are in place. So I think it identifies a really important priority. But I don’t think that we can just say we’ll let it spread in the younger people and hope that we can keep the nursing homes safe, because that has not worked so far.
Q: And then a follow-up, what do you make of the argument that social behavior has more to do with the spread of the virus than business reopenings? Have you parsed the data on that? Like as far as cell phone usage that tracks how far people have gone outside their homes? Is there a link between the reopening and the resurgence of these cases in the South and particularly in Florida, in your eyes?
MARC LIPSITCH: I have not tried to separate those out. Next time my colleague Caroline Buckee is on one of these calls, you should ask her, because it’s an area that she works more closely in. But I think the age association makes that more plausible. But of course, those same people also have jobs and go to businesses as consumers. So I think the age by itself doesn’t prove it, but is consistent with it.
MODERATOR: Next question.
Q: Thank you. I just had a question about your general thoughts on how the vaccine process is going so far. So are there particular candidates that you’ve seen preliminary data on that make you particularly hopeful? Or what does the data look to you: is something that looks promising or not? What are the concerns that you have? And then sort of in general the safety issue at the end of the process. Are we still going to know how safe it is in terms of giving it to large numbers of people?
MARC LIPSITCH: Yeah. So I think the first thing is, I don’t have privileged access to data from trials that haven’t reported. But I think this morning, I think it was this morning, the FDA released its guidance for clinical trials of these vaccines, which I thought was, on fairly quick read, very sensible and addressed many of the concerns—addressed, but didn’t solve, many of the concerns that people have had. One of those concerns is whether the vaccines are protective, are going to contribute to herd immunity by protecting people against infection, or whether they will simply reduce disease in those who become infected. And there was a call for at least a secondary outcome in trials to test whether that’s the case. The main concerns that I have about the development process, separate beyond the issues of distribution between countries that I mentioned earlier, is first that trying to get that evidence about the effect on herd immunity and infection is really important but challenging to do in a trial. So I think we need to focus efforts on figuring out how that’s going to be done, particularly in light of the animal data, limited animal data from from the Oxford vaccine, that suggests that the effect was mainly on symptoms. I’m not sure that will be true in people. But it’s a it’s a live question and an important question to figure out. Another piece that was mentioned in the FDA guidance was the need for at least what they called adequate numbers of elderly in the in the clinical trials. Certainly, historically, many vaccines, and in particular flu vaccines, have been less immunogenic and less effective in the elderly than in the rest of the population. And because the elderly are the most affected by this virus in terms of the consequences, that obviously makes a huge difference as to how good a vaccine will be in terms of its impact on public health is whether it really works in the elderly, at least to protect them against disease.
In terms of safety, I think this vaccine will be like other vaccines that in the initial safety trials we’ll know about the possibility of events that happen in one in 10 or one in 100 people. And then after the phase three trials, if there are phase three trials done, we’ll know about the events, about safety issues that affect one in a thousand or one in 10000 people, sort of depending on the size of the trial. And so for something that’s as severe and threatening to the population as this virus, that’s a good margin of safety. Of course, we can’t know until… The rule of thumb is what’s known as the rule of three, that if you give a vaccine to X number of people and you don’t get an adverse event of a certain type, then that means that the frequency is very likely to be well below three, divided by X. So if you give it to three thousand people, then you’re pretty sure that it doesn’t happen, then you’re pretty sure that the frequency is less than one in a thousand.
So when we give it to three million people, then we’ll be able to know about events that are as rare as one in a million and so on. So, you know, I think by the time there’s been a phase three trial, if the safety looks good there, then that’s very encouraging, but it doesn’t, it can’t exclude extremely rare events. But that’s true of every vaccine.
This concludes the July 1st press conference.