You’re listening to a press conference from the Harvard T.H. Chan School of Public Health with Barry Bloom, professor of immunology and infectious diseases and former dean of the school, and Bill Hanage, associate professor of epidemiology. This call was recorded at 8:30 PM Eastern Time on Thursday, April 16.
Previous press conferences are linked at the bottom of this transcript.
Transcript
BARRY BLOOM: I’m happy to begin with a few comments that reflect on the President’s plan to reopen America. It is, I think, quite a thoughtful plan, and I would say some good things about it.
The first good thing is that it is really gradual phasing in the relaxation of measures and tailoring that to different parts of the country. It’s also good on the need during that process to continue distancing measures, like wearing masks and taking temperatures, for example, in businesses as they open. It’s good at suggesting sentinel surveillance, which we don’t have, particularly of the most vulnerable. In a way this is wishful thinking, but it’s absolutely essential if we’re to know the expense of the epidemic in any place at any time.
And another good thing is that there are no artificial timelines, no hardline dates. As they’ve emphasized the primary focuses on health data, on what is the safest way to open things up and allowing the data and priorities to come from the states.
On the downside, their criteria for decision-making, of exactly knowing when to go to step one, two and three are a bit vague. One concern for example is that they suggest that they would look for two weeks as cases go down. Two weeks is a very short time in the sense that there’s always a lag between infection and symptoms. So, I would personally feel comfortable if that’s a minimum figure and one goes a little further before relaxing some of the constraints that are in place.
For me, the ideal would be to get the numbers of cases down, such that there is confidence that every case can be identified and every contact can be identified and traced in any community. That also implies that you have a guarantee that if there’s a flare up, which is not given great thought in this report, that your hospitals have at the time of relaxation excess capacity to deal with potential flare ups and that’s what we know has happened in both Hong Kong and Singapore when they relaxed constraints.
It assumes that testing will be at a level that at the moment does not exist. For example, it isn’t at all clear on the importance of identifying people who are infected, asymptomatic and maybe contributing significantly to transmitting infection, and that means population testing and zero prevalence testing, which are mentioned, will have to be scaled up because they don’t know exists.
The question that ordinary people want to know is, am I susceptible and am I likely to be resistant and these are critical that depend on testing capacity, for knowing who can go back to work safely and who not. It’s not specific on having the mechanisms in place to test travelers from abroad and other states. And that’s been where in places like Hong Kong and Singapore, Korea, and Japan, reintroduction of new cases that really have to be tracked down.
And that requires something that I believe isn’t in the report, which is identifying people who come in, particularly in planes, identifying them, knowing where they will stay, tracking them by cell phone or some other mechanism to be able to identify if they get ill and to identify their contacts, and ask them to stay in quarantine for two weeks.
And it doesn’t really determine the decision points for when we recognize that we have to go back and retighten some of the distancing constraints and at that level, informing the populace and the public in general, that is all tentative, we will be driven by the data and we have to accept the possibility that things will get more stringent before they relax. And again, that’s the experience in Hong Kong and Singapore, where both have had to retighten the social distance constraints. But overall, I would say very thoughtful, very carefully prepared document, which I’m very appreciative of.
MODERATOR: Thank you, Dr. Bloom. Dr. Hanage, do you have a few words you’d like to say?
BILL HANAGE: Yes, I do. I’d like to thank Dr. Bloom for what he was just saying. I agree with it very greatly and thought it was a great summary. I would also like to reiterate the fact that there is much to appreciate in this plan, including its stepwise sort of thinking and its thoughtful nature.
I would point out that the glaring problem within it remains, as Dr. Bloom was saying, the issues with testing. So, testing was the issue when we came in here. We want to be able to deploy sufficient tests so that we are going to be able to determine in the first place whether or not cases truly are declining.
And in the second part of that, as we were just saying, you want to know serologic tests so that people can tell whether or not they have been exposed and may be immune. And in general, when it comes to testing, as it has been all the way along here, we do need to go looking. I mean, it’s a case of seek and you will find. But then when you find, you probably also ought to be seeking a little bit more. Because figuring out what’s actually going on in the community is the key part of dealing with this pandemic. And we’re still early on in this pandemic. It’s going to be with us quite some time.
I think that the key thing that we have to see as things become relaxed is we need to prevent any future surge which threatens healthcare and testing is going to be absolutely crucial to that. And with that, I’ll just keep quiet and let people ask questions.
MODERATOR: Alright. Dr. Bloom, Dr. Hanage, thank you. It looks like we have our first question.
Q: I just wanted to ask them both to speak to, I mean you both mentioned serological testing. So, I just wondered if you could elaborate a little bit further on the importance in the distinction between, or need for both, you know, antibody testing, the serological session you’re talking about, and the need for, you know, continued expansion of testing for people who may be symptomatic.
BARRY BLOOM: Perhaps I would start and a kind of fantasy view of what I think is possible but not here at the moment. The ideal for testing for virus would be if everybody could test themselves, or at least prepare the test for diagnostic testing or infection testing at a commercial facility. And as you probably know, there are tests being developed that don’t require nasal swabs, that don’t require trained technical personnel to apply them, which are quite difficult, for example, in children. That isn’t mentioned in the White House report, but for me would be very important to know whether kids are infected and are able to transmit as they do for pneumococcal infections to older people, for example.
So, there are tests that depend on saliva that are being prepared. They’re being presented under emergency use to the FDA – I think one last week did get approval. That doesn’t mean they’re approved and guaranteed. That means they’re allowed to be under use but it means that they can prepare a sputum sample, send it to a lab and have a real PCR tests done. Similarly, the immunologic tests now require rather good laboratory sensitive assays for being prepared.
And again, in China and now with one approval in the US, there are little things that are like a pregnancy test or tests that can be used in hospitals routinely for diagnosing bacterial infections. They’re not that sensitive. But again, a drop of blood in your household with three bands to look at – one is the control, one is a test of the kit, and if the third band is there you have RGM, and if the fourth band is there you have IGG.
Knowing and appreciating that doesn’t guarantee are immune. But again, people could test themselves. They’re empowered. And if those data were provided to central sources within city states and the CDC, we could get overwhelmingly massive data in a very rapid way. And my guess is those tests will be rolled out in the next couple months. Bill?
BILL HANAGE: Thanks. That was excellent summary again, Yeah, the distinction is between a test which will tell you whether or not the viral genetic material can be detected within a sample, usually a swab.
As we were just hearing, saliva sputum would be a considerably better way of dealing with it and then that tells you if you are infected or you have evidence of recent infection. The other tests, the IGN and the IGG, show that you have been infected and those sort of – that’s the antibodies which develop following infection or during infection, and then can be detected afterwards to let you know that you’ve been exposed.
As we were just hearing, we don’t know at present the extent to which that guarantees infection. However, it’s the kind of information that would be of great value to people working in public health. And it would be great value to individual citizens because they will then be able to make judgments about their own lives and their exposure, which is information they will find really useful.
There’s one other really important thing, which is still a little bit obscure – all this and data are filtering out at the moment. The detection of genetic material in a swab does not necessarily mean that that individual is infectious at that moment, because it doesn’t necessarily correlate with the presence of viable and infectious virus. And understanding more about that will be really crucial to understanding how to give great advice about dealing with infected people, the cause of disease and indeed, obviously, some of the most important people in our community, the healthcare workers.
Q: Thank you.
MODERATOR: Alright, next question.
Q: I’m just trying to get a better sense of numbers. I know it’s clear we need mass testing and now I’m particularly talking about diagnostic tests, not serologic tests. With the point of care tests that are out there, there are two that are in use and approved and when I add up the numbers about how many of them are being done a day just in terms of how many of the test kits that these companies are shipping out and providing, it comes up to be about 1.5 million a month. We have a country of 330 million people. I’m just trying to figure out what is the number, roughly, we need to get to in terms of testing capacity of these points of care tests that we do have “mass testing”?
BARRY BLOOM: I’ll turf that one to Bill.
BILL HANAGE: Thank you. So, the recommendations which are coming out of WHO have been the in order to be confident that you are getting levels of surveillance, which are of a level that you can be pretty assured that you’re adequately surveilling the population you want about
10% of your tests to be coming back positive. Because you know if they’re all coming back positive, it means you’re obviously not capturing all of them. And I’m phrasing it very precisely in that way because of the fact is the pandemic is at a different stage and the local situation is different in all different places around the country. It’s very hard to compare the Bay Area with New York’s, for instance.
What I will also add to that is that there is some evidence if you look at recent data, that it appears that we may have an imperfect picture of the state of the pandemic in different parts of the country because it’s difficult to know if we are measuring actual underlying infections or testing capacity.
This is difficult to disentangle because of the fact that places which have a lot of infections, obviously, people are paying more attention and doing more tests, but at least some of what we’re seeing likely reflects local variation on the ground.
Q: Right. But do you have any idea. I get the point you’re making, so I’m asking something slightly different. Okay, what percentage of people would need to be tested? Say – I don’t know, maybe it’s not a percentage. But this idea that we don’t have the testing capacity that we need to make the determinations to move to phase one and phase two. And the question is, like, at what point, I know that the serological tets in terms of rolling them out are still a few months away, so now our best thing are these point of care diagnostics. How many need to be done in the next month, would you say, in terms of the millions to start to give a better picture of that? You’re saying if you look, we’ll find. Well, how many do we have to do to sort of get a better sense of the true denominator here? And how many people, you know, are infected?
BILL HANAGE: Unfortunately, I cannot give you a simple percentage answer because it will depend upon the situation which is local anywhere on the ground. What I will say is that, you know, the lower the percentage of tests that are doing that are coming back positive, the better because it means that you are not exhausting our tests on – you’re not basically finding a lot of people who are undetected.
The other question, though, which is crucial to this and which is sort of buried within it, is the capacity to do population-level testing in order to detect people who are currently asymptomatic. Because there’s increasing evidence, if you look at Iceland for instance, if you do a large very, very large population-level sampling, you can identify a fraction of the population, which is not displaying any symptoms at all. I don’t want to go into the talking about asymptomatic infection or transmission because of the fact that we do not know if those people will remain asymptomatic.
So we have this unfortunate situation where the ideal amount of testing would be everybody get was able to get a test every morning and go about their day with that information in mind, but we’re just not going to be able to get there and the extent which is going to be achievable in different places and it’s going to have public health impact, will vary depending on what’s actually going on in different places at that time.
Q: Got it. And just to be clear that large population sampling needs to be done by the serological test?
BILL HANAGE: Yeah, we’d like to see large – but I mean it would be wonderful to be able to get large scale population sampling on both scales. I mean, one of the reasons for this is going to be – as I said, the crucial thing after relation is going to be to prevent surges. And one of the best ways you’re going to be able to know to detect surges is catching those cases in the community and their contacts before they manage to transmit to other people.
So again, testing is absolutely key to this and I would be – as I say, I’ll emphasize that WHO says that 10% of tests should be coming back positive. I would personally like to see a lower percentage because that shows that you’re really, really going for it. But obviously, like I say, it varies very much depending on local conditions.
Q: Thank you.
MODERATOR: And next question.
Q: Hi, I’m wondering if you could speak to the role that contact tracing is going to have to play in any easing of social distancing measures. And whether we’re anywhere close to having the sort of infrastructure in place either in terms of people or technology for that to happen and what role the federal government might play in scaling that up, or whether state level responses are more appropriate.
BARRY BLOOM: Maybe I could start with some thoughts on that. I think, working backwards, the way an outbreak or epidemic ends is when the chain of transmission stops. And if you have a patient and 10 contacts and five of them are identified and the other five are able to get sick and spread infection, the chain of transmission expands exponentially. So, it depends on two things: where do you start from to be able to identify every single case and every single contact, and when you have 4,000 new cases a day, there’s no possibility of a workforce of any size to be able to deal with that.
And so, what isn’t in the report is when do you say the hospitals have capacity and there are sufficiently few new cases with respiratory disease identified as coronavirus that enables you to find every contact of those cases that have been identified in the system. It still leaves open the asymptomatics who may be spreading it, but at least if you can work from the patients backwards, you can stop a lot of chains of transmissions.
So, in my view, the workforce, either personal public health force, as you know in Boston Partners in Health and the city of Boston is going to try to get 100,000 volunteers are actually not volunteers, but paid volunteers, to track down every contract that has been known to a hospital in the Boston area. That’s a very labor-intensive way to do it. In China and Hong Kong, as you all know, there are cell phone contacts so that in this conglomeration of Apple and Google trying to identify everybody who has come within a short distance of your cell phone and indicating, hopefully in an anonymous way, that you need to get tested because you were in contact, we believe with someone who has identified as a case.
We could do a lot better. Whether the privacy concerns would override the public health concerns is unclear to me. But unless we amplify the testing capacity of tracking down context, that trains of chains of transmission will continue to expand.
BILL HANAGE: Yeah, I completely agree with Barry. I mean, the most crucial time for contact tracing is at the start, and at the end. And in the middle, then it’s – I mean, there’s some Herculean efforts which are going on, and obviously, anybody who is a contact of unknown case should be being very, very careful. However, the actual process of contact tracing is not most valuable at that stage.
I will also echo the comments about clever digital-based approaches in which you might hope that you could come up with a way in which you would be able to alert people to the potential that they had been in a place which was placing them at risk and encourage them to seek testing. That might also give us some indication about the possibility of a future surge, because if you know that there is a large amount of potential cases which are being detected among individuals who have made potential contacts that again could give us just the opportunity to get a little bit ahead of the curve. Because this is, as I said, the first time I started talking to people, and I think I might have said it to you, John, the whole thing is that when you’ve been looking at this pandemic as it starting, the place where you see it now is pretty much – it’s only a reflection of where it’s been in the past. So, it has managed to get in there somehow.
And maybe by testing the context of some of these known cases, you might even be able to detect people who have been asymptomatic. And so again, testing is such an absolutely crucial thing. And yet, the most important time for contact tracing will be when we’re trying to stop it starting up again and we’re trying to absolutely just stamp it out.
MODERATOR: Okay, next question.
Q: Hi, doctors, thanks so much for taking our calls this evening and for sharing your expertise. Obviously, you know, I think there’s a lot of uncertainty among folks and obviously just not sure what lies ahead. So, we really, really appreciate your insight and helping us navigate what lies ahead so that we are able to share with our viewers.
So here in Oklahoma – and obviously sort of what you have both been referencing is the importance of knowing the local numbers – so, here in Oklahoma, we have a population of about 4 million with about 30,000 tested so far, so less than 1%. We have about 2,300 positive cases, and we’ve had 131 deaths by so far. The concern statewide has been the lack of testing on and I think we have not had a statewide shelter in place that includes everybody. Oklahoma City and Tulsa are two major metropolitan areas that do have those instituted by their mayors, but going forward, I think we’re unsure what’s about to lie ahead. Our governor’s talked about opening things up fairly soon. And the mayors have been sort of on the other side with wanting to keep the shelter in place orders ahead.
Everybody has news conferences scheduled for tomorrow, but you know, we’ll see what happens and what shakes out. But just wanting to know from your expertise, what you would say, knowing the testing and knowing sort of where we are right now in terms of what you believe.
BILL HANAGE: So, thank you. Thank you very much for the question. So, looking at the numbers – I just jotted them down and thought about them, you haven’t really been – it looks as if you could stand to do a lot more testing.
The other thing I’m going to point out is the difference between what happened in Wuhan in China when they put in their very extreme social distancing when they had 495 cases. As you know, they had to build two extra hospitals and healthcare was overwhelmed. Now in neighboring provinces when they shut down at a much earlier level, they did not have an initial surge remotely like that.
So, that is, I’m not saying that because those numbers are exactly equivalent to what you have, because there are – you know it depends on where the cases are, whether in population centers and things like that. What I would strongly suggest is that people who are leading local communities think very carefully about putting in elements of physical distancing early. The reason I say that is because as I started out saying, it makes all the difference between what happened in Wuhan versus what happened in say, neighboring Guangzhou.
And I also want to point out that there is something of a perception which is rural America has been somewhat spared. And if you actually look carefully, you realize that’s not the case. It’s just patchy. Some places of being harder than others, and that is, I want to tell you, exactly what you expect in the early stages of a pandemic, because this is a point at which you will find some places hard hit and other places less hard hit as a result of the fact that the random chance of how many cases were introduced to them. And depending on where you are, you might have less local health care capacity as well.
So, I would really encourage people to think extremely carefully and do everything they can to prepare that, in case there is something which clearly signifies things are getting worse, to be able to take appropriate action accordingly.
BARRY BLOOM: I would just chip in to emphasize one of the key points that Bill mentioned. If the mayors in certain places wish to relax the social distancing, I would ask them to do so in a very gradual and stepwise fashion in the sense that we don’t do enough temperature testing in businesses. If you have a large company, a large factory, it’s not a big deal. It’s not the most sensitive test in the world. But it is a screen that keeps people conscious of the fact that we have an obligation not to infect other people. I’m a big believer in maintaining wearing masks. Again, they’re not all that efficient, which may be a virtue, and if they reduce the dose of virus that is spread from one to another, maybe they’ll create more asymptomatic infections and not severe infections.
So, if cities and towns open up, it should be in a way that maintains everyone’s awareness to be careful of interactions with other people. Large gatherings. And in this country, and I grew up in Kansas, so I have a sense that worship services are a big deal once a week – I would be very cautious about movie theaters and any events that have large numbers of people together until the community gets some confidence and the public health community gets some data to suggest that they really have a low enough level not to be so concerned.
Q: I greatly appreciate both of those. That’s very insightful and I think that will be very, very helpful for our viewers to hear. And, just to your point, for both of your points that you made – so, Dr. Hanage, when you were talking about the rural community. So, we don’t know – we’ve asked and we’ve put in a request to get the data for the number of people in our rural communities who have been tested, but we don’t know that those numbers yet. We do have outbreaks in nursing homes already that we’re starting to see spike just within the last few days and their death numbers going up, but we have three, even just within the Tulsa metro, where we’ve seen spikes this week.
So, to your point about the testing when we’ve tested less than % of our population, what would be a testing number that the – testing has been a major issue here in our state with even people being able to get tests and finding places to get tests. We’re still only testing those who are extremely sick, high-risk categories, and healthcare workers are just now starting to kind of come in, but it’s been a very, very difficult thing for people to find testing in terms of if you asked me tonight, where you could go get tested, I would not know where to send you immediately and it would be a major thing for you to get tested. So, I mean, it would not be just something quickly that you could go get tested.
So, in terms of testing, when you say, you know, you’d feel more comfortable seeing more testing, could you speak a little bit more to that?
BILL HANAGE: Got it. Yeah, absolutely. I mean, again, I cannot give you an exact number because I don’t know how many you would need to test before you started, you know, getting a fewer proportion of the tests coming back positive. So, the answer there is really just more, absolutely more. Just take this seriously and scrutinize what’s happening in your communities. Take this seriously.
As you build them up, the first thing you need to do is you have to build up tests so there are enough to ensure that sick people are receiving appropriate treatment and isolated from those who they might infect. Then you have to have things for healthcare workers and then once you get beyond that, you want to be going out into the community, you want to be checking people who work in those nursing homes, and you want to be starting to get a level of the amount of community transmission there is.
And I just want to speak to something that Barry said about, you know, worship and movie theaters. We know that one of the things which is important when you get this pandemic introduced to a place is the opportunity for what we call super spreading events, which is when somebody walks into a place and infects in short order, a large number of people. And those people don’t know they’re infected and that just sets off all those little brush fires along their own transmission chain, and people – you realize if they’re not testing enough, a couple of weeks down the line, when the sick people start rolling into the emergency rooms. And so, this really underlines the importance and testing and it just shows that it’s something which is important everywhere.
BARRY BLOOM: It’s a wonderful follow up question. We have a lesson to learn from China in this respect. They have the equivalent of WhatsApp called WeChat, and anywhere, as I understand it, in China, in any place or town, you can dial into your social networking chat and ask the question, where can I go for a test. And you can find that out. And where can I go if I feel sick and you can find that out in your neighborhood or district
With all the sophistication that we have and high tech in this country, again with my reflection on Kansas, it’s appalling that we don’t have high speed internet at every place, particularly in rural areas where telemedicine has got to be important in this context and telling people that live in large distances away from testing places, where they can most conveniently go for testing, and where they can go for care if they need it. And I would say if I were in Oklahoma, I would really bang on the state and the cities to make that possible.
Q: So, when you were speaking about, you know, Kansas, you, you nailed it on the head when you said, you know, thankfully, everybody in Tulsa and Oklahoma City, the two most populated areas have been very good about the shelter at home places.
You know the mayors of both communities when I hadn’t, took that additional step, even though we don’t have a statewide shelter in place but you nailed it. I mean, it has been a big adjustment because people are used to going to church every Sunday. They’re used to going to church on Wednesdays, are used to going to the restaurants and movies on Friday night, and all of those things.
And you’re saying, what would your message be to folks who would say, you know, our peak of hospitalization we know isn’t even supposed to be until sometime at the beginning of May. We’re in our peak contagion week this , so What would your message be to folks who are like, well, we’re sick of being home and we’re ready to have things lifted and that type of thing? What would your point be, you know, if we do see mayor’s tomorrow, extend the shelter in place orders past April 30. I mean, what would your message be to that to folks at home who may say, I’m sick of being home and we’re ready to be out?
BARRY BLOOM: I would say it’s a lot better to be home than in a hospital. And I just think that this is an example where our individual prerogatives have to give way to what’s best for everybody else until we know the coast is clear. And I think no one can believe anywhere in this country that the coast is clear, just as we didn’t believe when the numbers were low, as Bill said, they go up exponentially. We see low numbers today for 100 cases today, six weeks from now at 65,000 cases. That’s the power of this infection and that message has to be indicated to people that one slip – Bill is very concerned, I am too, about rebounding of second and third waves. History is on our side. That’s what happened in 1918. There were three peaks, the second peak was much worse than the first. And it’s harder to catch up with a second piece and reinstitute distancing than the first.
It wasn’t just 1918. In 2003 with SARS, Toronto took off the brakes and it wasn’t nearly as transmissible an infection as COVID-19 but again they had a flare and it took them weeks to get back. This has to be explained over and over to the people, that the risks are very great until we know what the risks are.
Q: Yes. Yeah, definitely. Thank you so much. I really appreciate the insight from both of you all. Thank you both very much, doctors.
BILL HANAGE: Thank you.
MODERATOR: Alright, next question.
Q: Hello, Doctor. So, my question is a relatively simple one. With the lack of testing throughout the nation, should any local leader or governor feel confident that they could enter stage one of this reopening plan anytime in the near future, either tomorrow or next week?
BARRY BLOOM: My answer would be, of course, no until the numbers of cases show that they’re going down and the numbers are such that the local hospitals are able to take a surge of 10 times the number of patients they currently have. What I think has to be made clear is the bending of the curve is not really bending the curve of the epidemic, it’s bending the curve to keep it below the capacity of hospitals to take care of people who are really sick.
And if you can take care of people that are sick, and you have a bit of leeway to be able to take a sudden rise in that as you relax the constraints, and then there’s a bit of a burst or a traveler comes in from Europe, or New York, if you can handle that, then I would feel quite confident to start beginning to relax the constraints. Keeping them on big gatherings of people and encouraging people still to wash their hands but enabling people to go back to work in a staged fashion, particularly if at the workplace distancing is maintained and some scrutiny, let’s say temperature testing, gives everybody confidence that people are aware of the problem and on top of it.
BILL HANAGE: Yeah, I mean, I think the only modification I’d make to Barry’s initial statement of no probably be to say hell no.
I mean, what we have right now is a situation where we need to be absolutely cognizant of exactly what he said, which is that when we’re flattening the curve, when it’s doing that, that’s us that’s doing that by our actions. Our actions are doing that. It’s not something which is happening because of the immunity that is generating, that’s down to us. That’s an achievement which the human beings are having over the virus. So, when it comes down again, again, that’s on us. And when we stop doing the things which have been having that effect, well the virus is still going to be there. It’s a pandemic. It’s not going to go away.
So, what we’re going to need to do is, at least until we have a situation where it’s either so rare and as Barry was saying, we feel like we can deal with flare ups, or there is a degree of population level immunity, then we have to be absolutely careful about exactly what’s going to happen as we start going back to work and getting closer to normal. And that’s one of the reasons why I kind of, I like the stepwise angle of this. I like the idea that it’s not going to just say, oh, [snaps fingers] back to normal, because that’s not the right way to do it. The right way to do it is to be prepared for the fact that you could have further surges. And if you do, you need to have the kind of hospital capacity that we were just talking about in order to prepare.
Q: Alright, thank you both very much.
BILL HANAGE: Thank you.
MODERATOR: Okay, next question.
Q: I have a question about testing capacity and especially looking at the serological testing because we’re in April now. In four months, we theoretically have millions and millions of children going back to school. Will we need serological testing at that point? And from what you were just saying, it’s sounding like you’re not anticipating that’s going to be ready in four months, or certainly not ready at the scale we’ll need it. So, what are your thoughts on that?
BARRY BLOOM: Maybe I can start because I raised the issue of school kids. I’m very concerned. I would think, for me, that would be an enormously high priority in every community for two reasons.
Disrupting schools sets back our kids in very difficult ways, particularly kids from low income families. It also straps families, so that the disruption that a lack of or closure of schools has is enormous. The second point is there was a governor, I won’t say who, who had said that there was no reason not to open schools because the data on this coronavirus indicates it kills primarily people over 60 and kids are not a big problem.
We know two things. We know that kids actually, if they do get this thing, can become quite sick and several have died. But the more important thing is we’ve learned from other infectious diseases that while kids can handle infections and are remarkably resilient, they carry those infections to Grandma and Grandpa, who are enormously vulnerable in this situation. We know, and we’re quite surprised that by vaccinating children with a pneumococcal vaccine, pneumonias in grandparent-aged people disappeared or almost disappeared, even though they themselves were not immunized because the kids were not transmitting it to them.
So, this puts in my view, a very high priority on understanding what percentage of kids have the infection, and a sputum test would surely be much more helpful than a nasal probe cast, which is tricky to give to wiggly kids. But we have to know that in order to make a decision on whether kids are a) infected and b) have the capacity to transmit, or their infection is so mild that they may test positive but they don’t have enough virus to spread. And we have no information anywhere in the world on that to my knowledge. So, I would put a priority on of the groups to get actively tested in the best way possible, I would put school age kids high on my priority list. Bill?
BILL HANAGE: I completely agree on every single point. I recognize, personally, the difficulty of having those kids at home. If you can imagine, this is a house which has two infectious disease epidemiologists in it working on the pandemic and two children downstairs going feral. I mean the fairly – it’s a difficult circumstance.
The situation with the kids is, as we were just hearing from Barry, they can get very badly sick. They do not seem to usually get sick badly with the same frequency as older adults. However, that doesn’t necessarily mean they are unable to transmit, and even if – we know already that asymptomatic transmission is a thing with this virus. So, given the fact that children don’t seem to get as severe symptoms as often actually make us very alert to it. And even if they are less infectious, kids make a different sort of set of contacts from adults.
So, if the schools are open, they can still become places where relatively large numbers of cases could be built up and then, if you then send them back, then they can infect their parents, or their grandparents. Or if you really want to – you know, the worst-case scenario in that circumstances would be closing the schools but not doing anything about workplaces, so the grandparents get pulled into care for the children and they probably transmitted them.
So, I mean I think understanding children and their role in transmission is incredibly important. The only thing I’ll add is that seeing positive serology in children will show that they’ve been infected, but it will not necessarily tell us how infectious they were when they were infected and so that has to be a priority as well.
Q: Hey, I mean, from what I’m hearing from both of you, and this and other questions, the biggest roadblock we seem to be facing is the accessibility of really broad testing. I mean, ideally, we’d want to do it every day, and we’re very, very far from that. Can we successfully reopen the country if we don’t have access to that?
BILL HANAGE: Who wants to go first?
BARRY BLOOM: No. And I think that it’s not two public health professors at Harvard who are going that in the real world. There will be places that jump the gun and, as Bill said, the most important thing is to recognize if it starts to surge again, then speed is absolutely of the essence. And the only way to do that is if you start to see cases coming to hospitals, you better be able to trace their contacts, because everything goes up by an exponential fraction
BILL HANAGE: Yes. Absolutely right. I mean, I think we’ve seen that in the early stages of this when it’s been taking off and uncontrolled, the doubling time is about three and a half days to, you know, three and a half, four days. And I remember talking to people here who I’d say you need to do something about this. And they would say, oh, well, I put something on the agenda for Thursday, which means we’ll discuss at the meeting next Monday. And I would say to them, that’s two doubling times away, you know. That’s not how you respond to an exponential.
And so, I think that one of the other things, and Barry alluded in his opening remarks, in preparing for the future, it’s a really good idea to have a set of plans, so when something happens, when a particular criterion is met, and that can be, you know, discuss it in your community, but that could be a certain number of cases, or it could be a certain number of positives in the testing, that can doing certain number of uncaught transmission chains, then you have a decision for what you’re going to do right then.
And it’s a trigger. It’s not something which you talk about. It’s not something you argue about. It’s just something you do. And if you decide that in advance, you’re probably in a better position to be making prompt decisions that will save lives.
Q: Hi. Thank you. Is 28 days of declining cases and meeting those other criteria enough time to safely send vulnerable populations out and about? Are the criteria rigorous enough for these vulnerable populations to reintegrate into the public within that amount of time?
BARRY BLOOM: The issue is the number of days that makes it safe to begin to do things. And, you know, the sense is that if people are infected now, they will become patent. That is, if they’re going to get sick, they will be identifiably sick in two weeks. And that’s why we ask people to become isolated for a period or quarantine for a period of two weeks. It is imperfect. Sometimes people take three weeks, and they can come back and then get sick. But it’s a compromise that seems to protect most of the people, most of the time.
I go back to the point that that two weeks for deciding policy should depend on the number of cases and the hospital capacity at that time. Two weeks if you’ve had three days running or 14 days running and still have an epidemic that has gone from one case, creating four cases to one case, creating 1.4 cases, two weeks is not going to make a whole lot of difference because the numbers of new infections are not going down.
And so I believe that until you know for sure that the number of new infections in your community and state, are going , time is not the decision point. It’s if you then relax the constraints, can you catch every test and isolate every contact?
BILL HANAGE: Yep. I’ll only add to that the fact that vulnerable individuals and vulnerable populations are exactly those we should be thinking about as we start potentially relaxing some of the restrictions. Because, as we know, and as we’ve heard on this call and this gets into a nursing home where an asymptomatic can wreak havoc. So, I think there’s going to be quite a long time that we’re going to be needing to protect folks like that.
One of the more thoughtful ideas for alternatives – I mean, it’s not something which is achievable on the time scale that we’ve been talking about – is what some people have called a stratified lockdown, in which you have some groups which are more restricted in what they can do than others based roughly on how we expect people to be affected if they do become infected. Now, I’m not going to say that I thoroughly agree with that. I will only make the comment that if you need to do that, it has to be very well planned.
So, I would say at the moment that, as we’ve said, the state of testing is such that we’re not really ready to be moving into this kind of stage one anywhere. And that even if we were to do so, I would be quite careful of those people who are going to be most vulnerable to the worst consequences of this if they do get infected.
Q: Thank you.
MODERATOR: Dr. Bloom, do you have any other final words before we end the call?
BARRY BLOOM: Oh, I’ll leave that to Bill.
MODERATOR: Alright, Dr. Hanage, is there anything else you’d like to say?
BILL HANAGE: I would just like to say it’s been a pleasure talking to all of you, especially Barry. Very nice to see you. I think, again, I want to reiterate something which is important for people realize: this is a marathon, not a sprint.
We are experiencing some success in some places by the actions that we have taken, but those are all successes that human beings have had from what we’ve done and we need to be very careful thinking about how we go forward.
This concludes the April 16 press conference.
Karestan Koenen, professor of psychiatric epidemiology (April 16, 2020)
Caroline Buckee, associate professor of epidemiology and associate director of the Center for Communicable Disease Dynamics (April 15, 2020)