Duke experts on Delta variant
Duke experts, including infectious disease specialist Dr. Cameron Wolfe, discuss the Delta variant and a spike in coronavirus cases that has some businesses and schools requiring masks indoors again.
Okay, hopefully Zuma's had time to add enough people in the we can go ahead and get started. Thank you everyone for joining us. Welcome to the latest Duke media briefing on the COVID-19 pandemic. Was hoping I wouldn't have to keep making that intro by now. But here we are. We have to Duke experts with us today to discuss growing covid outbreaks across the U. S. You're by the delta variants that are increasing hospitalizations mostly among among the unvaccinated. And yesterday the CDC recommended that even fully vaccinated people wear masks indoors in certain areas with us today to discuss all of this is David Monte Fury. He is a professor and director of the laboratory for AIDS vaccine research and development at the Duke University Medical Center where he has studied the emerging strains of covid 19 including the delta variant. Also joining us is Cameron Wolf. He is an infectious disease specialist at Duke Health and an associate professor at the School of Medicine where he studies infectious diseases and biological and emergency preparedness for hospital systems. Okay, um, what I'd like to start with you, uh, covid hospitalizations have doubled in north Carolina in the, in the last month. Is it inevitable? Those numbers are going to continue to increase? Or can we do anything at this point to reverse that trend? Yeah. Look, I appreciate the question and, and thank you for letting me lead off. Um, it's an important question to understand how, how someone gets to the hospital. I think because the answer, unfortunately, is at least in the next couple of weeks, we would anticipate that number going up. If you think about it. What we learned last year was that there's a certain delay in people being exposed to them becoming symptomatic to them, often getting a test, realizing they're sick enough to need to need further care and and then getting admitted and traditionally at least with previous variants, That timeline would be as long as 10-14 days. We would often sort of see the quite a lag time if you will between mitigation efforts that we would put into place and the impact on hospitalizations. So you're right, if you look at the hospitalization trend in north Carolina a couple of days ago, we crossed 1000 people again for the first time in quite a few months in terms of hospitalized bed numbers. And there's, it is it is baked into the system that that number is going to go up for at least a couple of weeks. I think that people have to be aware that that's going to happen because all of those people who have been exposed yesterday, for example, are not likely to sally gets sick for quite a few days, not likely to get sick enough to need the hospital for a further time. So, in fact, if you look at those numbers, our peak uh now towards the end of july often reflects what was going on in the middle of july and that reflect that increase that we were seeing then reflects of july the fourth kind of timeline David may comment I think as we go along. But one of the things we're seeing with the delta variant is that that timeline is condensed a little bit. You're in fact more infectious more quickly with this. So we are potentially seeing a hospitalization impact a little quicker than what we were doing. The people need to realize that exposures that have already happened and baked into the system for those people in ways that it's hard for us to avoid. The only real way we can avoid that at the moment actually is for people to be aware that if they test positive requires people to get testing still. But if they test positive, we do now have interventions in the form of antibody infusions. So synthetic monoclonal antibody infusions that can avert the sort of severe end of covid hospitalizations. So the one thing we do have up our sleeve if you test positive because you become symptomatic and it's important for people to get a test at this stage. Let your clinician? No, it is a wide group of people for whom there's benefit in actually getting those infusions and we can go into those details that people need. No, David. I'm not sure we're going to add to that. I don't know. Well, yes, Doctor Mani Fury, I'd like to to come to you now and start off. We know that obviously there's a lot of misinformation in general about covid but what are some of the most important things that people need to know right now about the delta variant in particular? Well I just want to emphasize what we've been hearing on the news every day is how contagious this new delta variant is. Um It's important to recognize that this virus has been evolving since the very start of the pandemic to become more and more contagious. Um It started last year, early last year with the D 6 14 G mutation. That particular form of the virus. Over a matter of only about six weeks um rapidly replaced the initial Wuhan form of the virus. It was that much more contagious. And then towards the end of last year and the early part of this year we saw the alpha variant from the UK come in and that slowly overtook the D 6 14 G variant of the virus. It was out competing and even more contagious than that one. And now we see the delta variant and again very rapidly that is out competing the other variants, including even the alpha variants. So it is now at a level where it's much much more contagious then it's ever been before. And unless we can shut this pandemic down it's possible that this virus is going to continue to become even more contagious and be even more of a problem. Absolutely, thank you both. Um we're going to open up to questions now you can pose questions in the Q and a window any time. And if you'd like to ask a question in person you can raise your hand in zoo and we can a mute you when your turn comes around. If you're calling in by phone you can raise your hand by pressing start nine, we'll say thank you to everybody who submit questions in advance. We have way more of those that we can even get to in an hour. So we're going to crack on with those. But do you pose your questions in the Q and a window and we will get to them if we can. Um okay. It's hard to know where to start really, but we uh, one of the important things clearly to note is that the CDC yesterday recommended masking indoors in certain areas here in north Carolina, 79 of the 100 counties already fall into that and dr walt. What I'd like to ask you is does it just make sense right now for everybody in north Carolina where they're going out in public to mask up indoors, given that already so many of the counties are actually in that place. Do we kind of need to do that to try and get ahead of this thing? I mean, I think the simple answer is yes to be frank. Um, not to intentionally go against what the CDC said, they're obviously trying to draw a line um, in the sand as to a degree of severity that you see within your local area. Um, but, but I think what we'll see is like we said earlier, this is that we expect this incline to be rising. And I think if you look at your county today, so for example, for us to look at Durham County, we are just outside that highest risk transmission area. But, but one step below it, I think people need to be highly aware of the fact that this is changing and a little deteriorated over the last few weeks. And if you're in a county that has not yet reached that threshold, there's a, there's a fair chance that you may in fact across that threshold fairly soon. So I think that the implications for health departments and for state health departments are pretty clear here. They have to at least if they're not going to put in statewide commentary, keep very visible view on how their county is performing because even as I said, if you, if you're not in that high or extreme risk category, according to city, see now you may well be within the next week. That's the kind of acceleration that I think that we've seen. So practically is it easier to sometimes apply that in a broader brush? I think it is. I think that certainly takes away the pressure for individual counties, individual patients to look at their own risk and try and judge how it's, how it impacts them. Um, I have certainly got to the point with all of my patients to not worry about which county they are from. I can give them individual advice as to how immuno suppressed or how vaccine was positively maybe. But at the end of the day sometimes it's easier just to say, look, we're in a very fluid situation here where rates are increasing. So a mask is a very simple thing that we have learned how to do well over the previous 12 months and going back to that and adapting as the virus has adapted is actually a pretty standard thing that we should be able to do. So yes, I'd be in favor of broadening it as wide as we can. Sure. Absolutely. Thank you. Doctor Montefiore. We know that vaccinations are the main thing that can help to emerge from the pandemic And we know that people have some hesitancy about that. Could you talk to us a little bit and tell us what you tell people who have concerns, for example about the new technologies that are used in the Covid vaccines that some people have been concerned about. Yeah, there are multiple reasons why people have hesitancy to get the vaccine. And when I talk to people, I you know, first try to find out what their reasons are for hesitancy. And most of the time it's based on either a lack of information or incorrect information. Uh And one of the things that I often hear from people is that they are concerned about the new technology. It hasn't been around for a very long time and they have some fears about it. And what I tell these people is that vaccines have been around for a long time. And That modern backs enology began 225 years ago when Edward Jenner used liquid from the postural on a milkmaid who had cowpox to immunize against human smallpox. Now, you know as with most technologies, vaccine technologies fortunately evolved and improved over the years to make vaccines safer and more effective. We now have relatively new technologies for covid vaccines that have been administered to billions of people. You can think of these new technologies as new iphones of vaccines where you want to be one of the first in line to get one while supplies last. And fortunately supply hasn't been an issue for Covid vaccines. They're readily available and they're free. Uh So most people wouldn't turn down an opportunity to get a free iphone or free internet service. Why turn down an opportunity to get a free vaccine that could save your life and the life of your loved ones and and help bring an end to this pandemic. And another thing to keep in mind is that these vaccines are only present in the body for a short period of time. Uh this is why you need a second dose of the vaccine, some of the vaccines after 3 to 4 weeks, once the vaccines are gone, the only thing they leave behind is an immune response that protects you from Covid David. You you highlight a couple of really important points there. The first is that these are not brand new vaccines. They have in fact built on technology that has evolved and built on science that has evolved over decades. That's really important for people to recognize because even with relatively newer designs, like we see in our MRNA vaccines Even they have been building to this point for 10-15 years. Our recognition of Covid is something we need to use that vaccine for maybe new, but that does not reflect a lack of safety or a lack of understanding of the science of how those vaccines work. In fact, that is well established. So, I mean, that's a conversation I frequently have with patients to say, Okay, we didn't we didn't begin this in 2020. This is this is a road that in fact has come to this point over many, many decades. Absolutely. Thank you both for highlighting that. Of course it's worth stating that so much of the modern vaccine technology came about because of the kind of HIV AIDS research that's taking place at the Human vaccine institute. Dr Bonnie Fury is involved in doctor if I wanna stay with you for a minute and talk about hospitalizations. It seems that the general sense or the general understanding across the country is that the increase in hospitalizations is a mostly unvaccinated people and be mostly people who were infected with the delta variant. Has that been your experience? And is it dangerous to make that as a broad assumption? I think that's probably true as a generalization with a couple of caveats. I mean it's definitely true that the delta variant is now the most heavily represented in most if not all of our hospitals. That's true for us here. I do because of the reasons that we said before, it's more infectious, you get sick a little quicker. We've had problems with the unvaccinated as we said being being more exposed to this and frankly there's a severity that comes with this variant that is a little more severe. It's not just more easy transmit, it makes you more sick. I think the one caveat that's important to recognize there is that there are a number of people who have been vaccinated who do not respond to vaccines as efficiently as someone who's healthy. And so, for example, here at Duke, we do have a large transplant and chemotherapy, uh, immunology patient population. We do recognize now that there are those patients who may not respond as efficiently to vaccines as as general members of the community, they can still get hospitalist. So depending on the kind of patient mix that your hospital sees, you may have a greater proportion of immuno suppressed individuals. We have even in that group, however, now got increasingly better data to say that, look, their mortality from having been vaccinated. So if I vaccinated transplant patient, someone who's got chemo falls way down compared to that of the unvaccinated. So, you know, it's important that you bring up that discussion about vaccination and unvaccinated people being represented in the hospital populations because it is sadly what we are seeing true of any hospital. Sure, absolutely. And staying on that, the topic of vaccination rates, dr Monte fury, obviously, vaccination rates across the US are flattening, even though there is ample supply to vaccinate everybody do do those of you in the immunology world have a sense of what kind of percentage of the population we would need to reach. You know, in order to be able to quell the kind of outbreaks that we're seeing now and you know, can we get there um when we know that there are some people who are immuno suppressed and can't get vaccinated and maybe some people who have religious or other objections, do we have a sense of where we need to get to in order for to have some populations level safety. And that's a really good question. And you know, we're still learning what, what that number is. You know, when do you reach this So called herd immunity that you really start to turn things around? And I think what we're learning from the delta variant is that we haven't reached that point of herd immunity yet. The percentage of people who have been vaccinated combined with the percentage of people who have been infected and have some immunity. Um, you know, we really haven't reached that tipping point yet. Um, it looks like we might have before the delta variant came along. And that changed the dynamics. So, you know, clearly we need to be more rigorous in in our approach to vaccinating people. I think we need to vaccinate younger people too. And the Pfizer vaccine is now approved for Children 12-17 years old. We need to get some of the other vaccines approved for that age group as well, so that there's more vaccine available and we need to get approval to immunize Children who are under 12 years old. So, you know, we can't forget that part of the population either, they're going to remain vulnerable. That's going to remain a reservoir to um um keep this virus circulating. Um, so there's there's still, you know, always to go and exactly, you know, at what point we need to reach before we can really turn things around is something that, you know, we're still learning. The point is that point is perhaps a little different depending on where in the country you live. When you think about viral dynamics, it becomes more important in densely populated areas to in fact even drive that vaccination rate higher. So if you're sitting in new york, you're sitting in Chicago, you're sitting in an urban metropolitan, densely packed area. If your activity is that you play in a football team, If you're if you're doing something that's in a condensed space, your transmission rate goes up, therefore the vaccination rate that we need to achieve in that group has to go up to match that. So again, all those numbers a little different because of Delta probably all higher. Absolutely. Thank you for that additional context. Uh, thanks everybody for sending in so many questions. There are more than we can possibly get too. But I'm going to consolidate as many as possible so that we can get to as many of these as possible. And I would also know dr Monte Fury's comments about vaccinations for the under twelve's. There's research going on at Duke towards that and we will be having a briefing update on that. As news becomes available. Doctor Montefiore. I wanted to come back to you, you mentioned earlier about one of the main questions people have is about the technology. Another question that I've seen floating around in our chat and elsewhere is people saying, well, the delta variant is a variant, so the vaccine is no good against it. So therefore I shouldn't get vaccinated. How do you respond to that? Yeah. Well, the one nice thing about the delta variant is the vaccines still work against it. Uh And what and there's not a lot of efficacy data yet in the field that will be coming soon. It just hasn't been long enough to where that information. But in the meantime, what scientists like myself do is we study how susceptible that these variants are to the neutralizing antibodies that the vaccines inducing people. and what we have found in my lab and what other people have found is that the delta variant is still very susceptible to those neutralizing antibodies. So that that's really good news. In fact, it's much more susceptible to those neutralizing antibodies than the beta variant that was circulating in South Africa. And now the delta variant has become the dominant variant there. Which is which is bad because it's causing another spike of infections and a lot of deaths in South Africa because a very small percentage of the population is vaccinated. But it's good news because now the dominant variant there, the delta variant is likely to be more susceptible to the vaccines. So, you know, that's the good news that the virus, this delta variant has evolved to become more contagious. That's what viruses want to do. That's how they assure their survival. But it has not evolved to the point yet where it is escaping our vaccines to a substantial degree. Okay for that. And I think we need to cling to any shred of good news that we have right now. I'm going to kind of zoom out and and talk about some kind of out in the world things right now and and dr wolf, one thing that we know is coming is that in person school at least as of right now is set to resume. As of right now. At least the state of north Carolina is going to be requiring masks for elementary and middle school age Children. Of course high schoolers are old enough to get vaccinated, but the rates aren't great. What is your take on that currently? Do you think that the state should be recommending masking for high school students as well given the current situation? Yeah, I mean, I mean, the idea would be that we have our vaccination rates up in our high school students sufficient that that those sorts of mitigation efforts no longer become necessary. But I think, you know, if you look back at the last 12 months worth of experience, some of our colleagues here at Duke, actually within the abc collaborative, a large network of of pediatricians and ideally specialists across the country. In fact looked at those very questions and found that masking was in fact a very simple and yet effective strategy within the context of schools. So that falls in line actually with what has now been the guidance from the American Association pediatrics, who would also say the same thing, which is to say look as much as possible, um, masking within all school contexts. Um, and we can debate about whether that even stretches into college context is in fact a strategy that's effective. So, you know, I think the reality at the moment is that we're not going to be at those sorts of levels that David talked about earlier about vaccination rates within high school students to have that as an effective mitigation strategy in and of itself. And so in that context, masking is the next step down. That becomes very important, because at the end of the day, I think there's this unspoken value of having our kids back in school. I don't think anyone doubts that that's the right place for their own education and for for the better of all of our students, we're going to do that safely, because at the end of the day, you don't want your student being back at home quarantine or heaven forbid out of out of school for a period of time, sick. So we got, again, we, we got used to masks last year, we were all familiar with how to wear them. We're all capable of wearing them in ways that made school um actionable. And so again, I would stand on the side of the pediatric society and some of my colleagues here who who would be supportive of that. Absolutely thank you and appreciate your highlighting the work of the abc collaborative. We have briefly focused on their work a few weeks ago and next week we will be talking solely about school reopening and we'll have one of the abc pediatricians on with us. Um, before we, before we move off of this topic, we've had an interesting question come up as we think about being out and about in the world and ask should people be more careful outdoors than previously. Given that the delta variant has been shown to be more contagious. You know, we're starting to see a tentative reopening of outdoor concerts, outdoor gatherings. These kind of things. Do you think that we're moving towards recommendations of masking outdoors when we're in large groups also or is that something we should be all thinking about now? I think you need to understand what the risks are. It's not for me to comment on what you know, what have been political thoughts in the background about requirements there? I don't know but what we do know for this, for Delta in general, it's covid in general and Delta specifically is that proximity matters, ventilation matters so hence outdoors typically is a lower risk than indoors and vaccination status matters. And if all of those are still present, then a mask helps further to reduce the sort of dispersion of active viral particles. So I think it depends on what you're talking about your outdoor activity. Um, you know, if your outdoor activity is a spaced out game on the soccer field, in reality your risk is extremely low. So athletics last year, for example, were very good at going through degrees of proving that in fact on field transmissions were exceptionally uncommon, both in professional leagues in college and hospital. I think if your situation is an outdoor concert venue where for protracted periods of time you're sitting in close proximity, um, perhaps yelling and screaming at the concert, that risk has gone up and the way that it stands at the moment is our chance of having someone in close proximity to you who has unbeknownst to them, Covid has also gone up. So I think it's very event dependent. I would say the same for indoor activities. You know, I think your chance of having trouble at an indoor restaurant where you're sitting at a bar condensed in between 15 other people is automatically higher than if you're in a relatively spaced out indoor environment. So it's very it's very event dependent. But I think people at least need to be conscious that the background rates have gone up and that some of these events they need to be sensitive for particularly if you're someone who's high risk or unvaccinated. Sure, Absolutely. Thank you very much. Doctor Mani Fury, I'd like to come back to you and dr Wolf. I'd also like to get your take on this. Um we're hearing a lot about breakthrough infections and that some people who are vaccinated are again these breakthrough infections and what the question is is how common is it or is there any good data yet to show whether how how likely it is. A vaccinated person can transmit the virus after a breakthrough infection. And is that more likely than somebody who is unvaccinated? So um there are breakthrough infections that that are occurring. The actual rate isn't entirely clear and it probably depends on uh what the dominant variant is and where you are in the world but they do occur and what we know is that those are mostly mild cases are asymptomatic cases. Most people who are hospitalized are people who have not been vaccinated. Um But yet you know people who have been vaccinated um there there is a chance that they can get infected and um what we know about those cases is um you know they tend to be mild cases but those people are shedding virus um and they are capable of transmitting but they're shedding less virus than a non vaccinated person and they're shedding that virus for a shorter period of time. So they're they're contagious but far less contagious than a non infected person who get a non vaccinated person who gets infected. They still have had some cases. I think to be fair of transmission from vaccinated and breakthrough patients, I agree completely with what David said. They tend to be less severe, which is the reassuring thing, but they have virus. And so, you know, if that person is your spouse, if that person's person shares a close office space with you, if that person is in the baseball dugout with you, um, then then they can be transmission transmission vectors and they can pass it to other people. We have absolutely saying that. So if you're someone who gets a breakthrough infection and your housemate, your spouse is someone who is at high risk. So they're suppressed. For example. Um you know, I do think people need to be very sensitive about the fact that they can transmit in that situation and some of that, in fact I think has driven some of yesterday's CDC updates where they would say even if you're vaccinated, if you know you've been exposed, Um you know, please wear a mask and consider testing yourself at day 3-5 such that you know, if you're going to get a breakthrough infection and you can make decisions that therefore counteract your ability to pass that to someone else. Absolutely thank you so much. And just as a follow up, I know that we have a lot of people who are concerned that obviously if you're vaccinated you can get covid and be totally asymptomatic and never know it. Um and in those instances is there a risk that you are also contagious and is that something that people should be thinking about? Since obviously if enough people were vaccinated wouldn't matter because these the virus would pass between people who were vaccinated and didn't get sick predominantly. But since we know there are so many unvaccinated people do us as those of us who are vaccinated and never get any symptoms. Should we a cage? Should we be acting as if the potential is that that we're actually infected? It could pass it along. I mean it's less common that you'll be sick in the first place. Let's put that out there again and re emphasis it even in some of the cohorts that we've seen out of state Israel where where they vaccinated large swaths of their community very early on against delta variant, it's still providing vaccinated people with the two thirds less likelihood of getting sick. Like it's still highly effective. The question about asymptomatic transmission is always much more challenging because of course we never test people or rarely test people in asymptomatic fades. But it is true that people can shared virus before they get symptoms or before they know they are infected. So again, that sort of drives some of the decision making about masking. It leads public health officials to say if you're in an area which is highly prevalent for delta variant at the moment, you should be wearing masks indoors because I don't know if you're about to become symptomatic tomorrow. And those sorts of public interventions with masking then become more relevant in that setting. Sure that makes sense. Dr Money Fury. Another delta variant related question for you. And the question is do we have data on whether Children are more vulnerable to the delta variant than they were to the original strain of the virus? I'm not I'm not aware of any data that would suggest that there are any more vulnerable to the delta variant than adults are. Thank you for a very concise answer. Um uh uh not to pile doom and gloom on here. But one of the things that a lot of people are clearly curious about here is obviously this virus may take mutated quickly. You've said in previous briefings that that's what viruses do. But this one surprised scientists how quickly it mutated. Are there other variants? You know, there are occasional news stories about the land of Aryan and there are other variants that are on your radar that may be more or more concerning than the delta variant or what do we have any idea what the future might look like with this virus? Well, that's a very good question. And you know, I work together with a lot of scientists trying to figure that out. Um you know, we're part of a team that works with the people who are doing the genetic surveillance and looking at what other variants are out there. They're not prevalent enough to be a variant of interest or a variant of concern yet. But do they have the potential to escape our vaccines? Does this virus have the ability to completely escape our vaccines? That's a question that we're studying uh and and that other people are studying. But in the meantime, you know, we uh we by we I mean a large number of people, a large number of scientists and organizations in the field and this includes the U. S. Government, the NIH to W. H. O. C. D. C. And a lot of other places are being very closely watching what variants are appearing and how prevalent they are and and studying those as quickly as many of those and as quickly as possible to get an idea of what the next variant of concern might be. Well, thank you very much. Doctor will coming back to you, we've had a question about people's fatigue with constantly changing recommendations. Can you talk a little bit about how you know, we're watching science unfold and how it's important for the recommendations to how we can communicate to people that the recommendations have to change as our understanding of the science changes. Yeah, that's a terrific point. I mean I think we're all fatigued to be honest by by lots of things over the last 18 months. So I can sympathize with that with that sentiment. Look, I think one of the things that we've tried to tell people very early on and I hope as this has evolved, the people have understood that is that we are we are watching evolution in progress. I think David mentioned that phrase earlier. And because of that, this because this is a new virus deal for us frankly. Because of that, this will this will continue to ebb and flow in ways that are hard for us to predict that try as we might. And I think if we're going to become better at trying to respond to that, we need to be therefore prepared to have a little bit of give and take in the types of mitigation efforts that we have. The types of scientific recommendations that people here as we learn more that may that may involve changes to the recommendations that we do to keep people safe or treat them when they're sick. Um and that that flexibility is in fact really important if that didn't exist. If we did not have that sort of ability to flex and to give and to become more stringent or to relax. We need to. In fact, this would be much more difficult to control. Similarly, if it was a virus that was very predictable as respiratory viruses tend not to be, unfortunately, um this would be easier. But it's because we globally don't have this under control. And mutations that David were mentioning about continue to evolve and we have not reached a point where we've eliminated it domestically, that we have to have that flexibility. Um And I guess I would um you know, it would be wrong with me not to beg people to be patient with scientists as those public health recommendations and knowledge evolves as it will continue to do. Sure, thank you. Dr monte theory swimming back to you here. This is a question that we've already touched on in a number of different ways, but it's it's come out again point blank I want to give you the chance to reiterate it. Do people who have already had covid need to get vaccinated? Yes, they do. About a third. At least a third of people who've been infected. Um don't really mount a very strong immune response. These and these tend to be people who were either asymptomatic or had very mild infections. They don't mount a very strong immune response against this virus. But what we do know is um once they get the vaccine, their immunity goes up way high. They have really, really strong immunity. And so I strongly recommend people who have been infected to get the vaccine and to get both doses if it's a two dose vaccine. Absolutely, thank you. Dr Wolf, coming back to you were racing through as many of these questions as we can. Have a lot of questions following up on some of the stuff we talked about with hospitalization and people wondering with the delta variant, it seems like it's causing people to get sicker to get sicker faster. Can you talk about some of the symptoms maybe that we're seeing with the delta variant that are any different or more extreme than we saw with the original strain of the virus? Yeah, I mean I think we're number one, we're seeing it quicker. Um that I think there is now a growing body of evidence to say that this is probably making people symptomatic two days on average, sooner than when they were previously becoming symptomatic. We know more about its severity. So the likelihood of you becoming high pox IQ so short of breath has gone up. There's a lot of discussion about the sort of the less severe situations, whether people are getting the same degree of loss of smell that they did in the past, or whether people are getting more sort of um upper respiratory tract infection symptoms and they I think that is a bit variable to be honest and I wouldn't want people to huck on that. I think the important part is that it tends to be quicker. It tends to make we have seen an increase in younger individuals in the hospital. Um now that's a bit hard to tease apart because of course we've done a great job of vaccinating over 65, so they are not getting sick come into the hospital. So teasing apart whether the disproportional number of 20 and 30 and 40 year olds that I now have on my current wards is because Covid is behaving differently in them or because they are simply the unvaccinated. That I think needs a little bit of teasing apart. But we've certainly seen patients in whom their underlying risk factors do not seem that severe and yet they have needed hospital support. So I think there's something there that's changing in terms of severity uh, independent of the fact that the young tend to be the unvaccinated. Um, but to go back to a point, David mentioned earlier, also for the for the vaccinated, this has tended to become a very mild illness. We have we have driven this even if someone gets a breakthrough infection to feel for the most part like a common cold or flu virus, which is reassuring. Um, and still the majority of patients particularly young and healthy individuals, that may be all that they get from Covid. It doesn't mean they're not transmissible infectious to others. In fact, it's probably more likely with Delta. Um, but the symptoms otherwise feel under the same bucket of fevers, severe fatigue is probably the most common thing people would tell me sore throat, cough, sinus stuffiness and ultimately the more sinister finding of chest pain and breathlessness. Absolutely. Thank you. Doctor Montefiore. Coming back to you. We've had a number of questions along this line. Just some basic science stuff. Could you please explain a little bit how simply how more people getting vaccinated helps contain the virus and limit mutations? Yeah. So, um, there have been so many transmission events of this virus and every time the virus gets transmitted from one person to another, it has an opportunity to mutate to change. And so the more we can shut this pandemic down and slow down the spread of the virus, the less opportunities it's going to have to continue to mutate and and change and become more contagious and and potentially even escape our vaccines. The mutation rate is dependent on the transmission rate. How many times this virus has trans transferred from from one person to another. You know, how long it's been continuing to replicate in the human population? You know that that's what drives mutations and and and allows the accumulation of multiple mutations to occur that give us these finna types that we're seeing in these variants that are a particular concern right now. Sure, absolutely. Thank you. And following up on that, we've had a number of questions about boosters. Uh is there any data that suggests that boosters to a Covid vaccine would help? Do you think that maybe a direction that we're headed as a society? So I do think it's a direction that we're headed to? Um the question of when to boost and what the boost with is still an open question. But I think we're probably getting very close to a time where we're going to know um if and when a boost is necessary, I believe that boosting will be necessary. Um It's going to it's it's very likely going to strengthen the immune response against the variants. Uh There's experimental evidence for that. Now. There have been small clinical trials that have tested a third dose of the MMR vaccines and some of the other vaccines and the immunity does go up and it goes up against all of the variants. Um and so you know as time goes on and we see more and more breakthrough infections occurring and if there is an increase in breakthrough infections that lead to more severe disease, that's going to be the trigger that says okay now is the time to start boosting people again And we'll get an idea of what the level of immunity correlates with that timing of of when a boost is needed. So we'll know better in the future when an additional boost might be necessary. Thank you very much. And a follow up question to that people are asking when assuming that boost has become a thing. Will it be important for people to get a booster that is you know the same vaccination that they got originally. Will they be mixing and matching or do we not know yet? You know we we don't know yet. There are a number of clinical studies that are being conducted right now. They're called mix and match vaccine studies. So people who got the J and J vaccine are getting boosted with an M. RNA vaccine and vice versa. Um There's also the subunit protein vaccines that nova vaccine Sanofi have. Um So those types of clinical studies are being conducted now and they're looking at the immune responses that are being generated. Um It's not really possible to do those studies to look at efficacy anymore. So they're driven mostly by what's called immuno bridging. Looking at how strong the immune responses in laboratory test compared to what it was in the Phase three trials where there's this remarkable efficacy. So those studies are ongoing and I think, you know, for a matter of convenience and uh in terms of supply of vaccines that it's going to be important um to be able to not have to get boosted necessarily with the same vaccine that you got initially. And I think it will be possible um to have options available to you when it comes time to be boosted. Thank you very much. Doctor Wolf. You know, you you spoke eloquently a few minutes ago about the frustration and the weariness that everybody in society feels. But I can only imagine how magnified this must be against frontline healthcare workers when you're dealing with, you know, sicknesses that could potentially have been avoided. What is morale like amongst the, you know, the health care worker population and what's capacity like with cases on the increase, But obviously still a long way short of where they were at the worst peaks we've seen so far. Yeah, that's a pretty crucial question actually. Um, I can't speak as the voice for my entire workforce in terms of morale. I mean, I will say that we have learned as a health care system. Many intriguing ways to adapt. Let me put it that way, both in terms of our staffing models to allow flexibility and avoid fatigue, where we can to allow accommodations of more people into the system in ways that don't interrupt all of our normal activities that we have to keep doing as a hospital system. If you think back to March of last year, most non elected things within large healthcare system just stopped. We found ways of learning how to adapt to that. We are better at understanding our procurement channels of how we get personal protective equipment, how we free up medications, how we get oxygen supplies. All of those things have made handling a surge of cases easier than what they were in january or happen to be last year. But I think there, I mean it is absolutely a fatiguing element to see patients in front of you when you know that there was something that that person could have done to avoid that situation that is that is hard to face. Um you know, different people make choices for different reasons. It's because of their understanding of risk. It's because of the data that they have received. Um it's because of personal choice in some situations or their um health literacy and availability of good information. But for whatever the reason to see large numbers of unvaccinated people in the hospital really struggling and often at that point in their decision making, quite regretful for the situations that they've come through and and now find themselves in. Um that takes a toll. I mean I'd be wrong to say that some of my nursing staff, some of my medical staff and colleagues haven't felt um fatigued and taken and internalized a lot of that struggle. That's that's real Sure. Thank you, thank you very much for that. Um Also one if you already, I'd like to give it back to you. We know obviously that the all of the vaccines currently available available only under emergency youth authorizations. Um Do we know and I gather that the FDA is maybe too expected to start growing full acceptance in september would that, how much would that help? Um In terms of you know, whether it's vaccine mandates amongst individual institutions or government levels or encouraging more people to get vaccinated? Will that provide more tools in the box? Oh absolutely. There are a lot of people um where you know, knowing that the FDA has given full license shirt to the vaccine is going to make a big difference to them. Uh their organizations and companies that are also waiting for the full approval of the vaccines to um change their policies and requirements for vaccination for their employees. So I think we will see uh an additional surge in vaccinations when the FDA finally does approve these vaccines for full licensure. So, and we know that the Pfizer and Moderna vaccines and J and J and others uh those applications, you know, are in um it takes time for uh the FDA to evaluate everything they need to evaluate for those vaccines to give licensure. Um but from what I'm hearing, I think we can expect that some of these vaccines, especially the ones that got the earlier start. Pfizer and Moderna, might finally get approval for full licensure from the FDA in september. I think an important point if I can dr onto that Greg for folks to make sure they understand with FDA approval is that involves the passage of many other decisions outside of the safety realm. People I think often correlate FDA approval with a marker of safety that somehow has not been crossed yet. I want people to really understand that there are so many other logistic things that go into that that have nothing to do with safety. It's factory logistics, it's Q and A processing in the background, it's company follow up and procurement issues and in many logistic things that have nothing to do with the fact that these have been now distributed With over I think 340 million doses within the United States so far. We know more about the safety elements of these vaccines than we have learned for most other vaccines that have ever come to market. And so people need to understand that there's that differentiation of what the FDA is actually looking for for full approval. They have cleared this for safety markers already in ways that have led us vaccinate many of our people safely. That is a key differentiation. Sure, thank you both. Another question here that I'd like to hear, the perspective of both of you um is that whether there is or should be a separate case count for the delta variant? Just so that the general public kind of gets an idea of the seriousness of that particular variant and the surge. The comment here is that some people see a lack of separation in the case count as evidence that the delta variant is being over emphasised. So I'd like to hear both of you. You're takes on that. Well, I would say technically that's very difficult to do because it requires testing that isn't done routinely to know exactly what variant a person is infected with. So it would be linked uh to certain demographic information and what's known about the prevalence of a particular variant in various regions. But you wouldn't get a precise answer unless you were able to sequence the virus from everyone. And that's just not being done. That's it's not possible to do that. That's not a routine a test that's readily available. I mean the premises interesting though, because you can you can estimate that number. I totally agree. David, there's no way of getting sequencing so broad at current levels that we could know precisely. But we do have regional awareness of how frequent certain variants appear. For example, I know that we're sitting in the mid eighties, high eighties in terms of our numbers of delta variance proportionately in the hospital at the moment. So I think you could calculate a proportion and whether that would help people understand the gravity of this or not, I think is the question that then would play out. But yeah, precise sort of individual number accounts we can't get to. Yeah, but I do agree that it should be possible to get reasonable estimates and and it would be helpful to, you know, have those numbers. Absolutely. Thank you both. Um, and certainly there's enough doom and gloom to go around. But I have a question, David Mahon story about this. So given the vaccination rates in the US at least have largely flattened. Um, and if there aren't any strategies that end up increasing those, how long does it take a virus like this to work its way through an entire population to the point that everybody has either been infected and unfortunately being killed by the virus or develop some immunity to where we get to that mythical herd immunity that a lot of people talk about and don't necessarily understand myself included. Yeah, very good question. We'd all like an answer to it. Uh, and unfortunately we do not have enough information. Um, you know, to really uh understand how long it's going to take to reach this mythical or real herd immunity that is going to turn things around. I'm hoping it's not too far off. I'm hoping that ways will be found to encourage more people to get the vaccine so that we can shorten that length of time. But I haven't seen any real, you know, accurate estimates of that. Absolutely. Thank you. Um, we are rapidly moving towards time. Thank you everybody for all of the questions have tried to get to as many of them as we can. And I'm just whizzing through here to see if there's anything really that we haven't addressed. Um, don't mind if you are, here's one uh, for you, I know you've said obviously that you've been monitoring variance and uh your peers in the scientific community areas of concern. But at this point, what is the level of concern that a variant could pop up that is entirely resistant to to the to the currently circulating vaccines or what does it take for a variant to reach that kind of level? Well, those are questions that were trying to get answers to um you know, is it going to be possible for this virus to mutate in a way that it will um really substantially be able to escape our vaccines and still survive. Um A lot of times, mutations in the virus are also lethal to the virus. And if those are the mutations that are needed to escape the vaccines, then we don't have anything to worry about because the virus is going to um it's going to be a dead virus. So, you know, we're looking at naturally occurring variants and there are tens of thousands of variants of this virus out there. Um and you know, most of those variants are rare, but we're looking at them and trying to determine whether or not there is a variant that's possible that would remain viable and completely escaped the vaccines. Uh and and that might become enriched in a vaccinated population through breakthrough infections. Um and then, you know, through that process, start to propagate more and become a problem to our vaccines. So we don't know yet. We haven't, no one has identified a variant like that and naturally occurring variant like that so far, that's capable of evading our vaccines. Hopefully the virus will not be able to evolve to completely evade the vaccines. But it's an open question that's being studied extensively right now by our group and other groups. Well, thank you. Dr Wolf, maybe I'm grasping for a shred of optimism here, but I'm wondering, you know, we've talked about and you talked about the stress that's brought to healthcare workers when people come in with avoidable infections. But are you finding that unvaccinated people who are getting sick with the delta variant and and are coming through it and recovering come out of it with a renewed appreciation for the need for vaccinations. I mean, is that is that kind of happening? And mine is being changed? I think that I think that's absolutely occurred multiple times. I mean, I wish it, I wish it doesn't take an infection to change someone's mind, particularly severe ones. But I think you've seen that across the country, haven't you? There's been a number of talk show hosts that have dramatically changed their opinion about how much they are prepared to beat the drum for vaccinations. Look on a personal level, we see a lot of people who who come in and say, look, you know, I was thinking about this, I just haven't got around to it. Now. I sort of regret that decision and they're on the phone or texting their friends to go look, hey, you don't you don't want to have to go through this, please go ahead and get back to that as quick as you can. So it it does change people's opinion. There's no question about that. There's nothing, there's nothing fun about being hypoxic in a hospital, there's an awful situation to face. Um, and I wish that is not what motivates people to change, but it is compelling for those who had to go through that. And if and if, you know, if those people come out of that experience and proponents for aggressive vaccination campaigns, you know, they can really be influential because, you know, you can see their opinion having having evolved and changed and that could sway a lot of people. Do you think following up on that? But that could be a powerful evolution of the public health messaging is to get people who have survived covid and now understand the need for vaccinations. You know, people who are like friends and neighbors maybe of the unvaccinated, getting them out there, because it seems like public health messaging. You know, there were people who are ready to get the vaccine, we all got the vaccine and now reaching these other people, Maybe it takes more than just the experts talking about this. Do you think that could make a difference? Are you seeing that happening in public health messages? Yeah, I think that's an important question is it's sort of the underlying premise there is have we, have we, have we exhausted our current method of messaging to the unvaccinated? And do we need to pivot and craft that message in a different way or have them receive it through a different medium? And I think that's absolutely true. You know, I was very pleased in recent weeks to see some directional change with certain elements of the media in terms of their their open and willingness to talk about vaccination and its benefits. For example, can you do it through recovered individuals? Absolutely. Can you make that, can you make that pitch um, through other means that help people reach an understanding? I think that's very true and we need to continue to try and honestly find ways of, of reaching people who may have heard the message so far, but for whom that has not answered their questions or their concerns and many of those concerns are entirely valid. One of the things that I think has been really helpful for me is I meet a lot of people in clinic where I can sit down and have this as a one on one conversation. It's a trusted conversation in the confines of a clinic space. Many people who would say, Look, you you've helped me answer and reassure me as to the questions that I had that I wasn't hearing in the media and and and you know, you've been my doctor for 5, 10, 20 years and so therefore, yes, I'll go and get it today. Those kind of conversations often happen on really individual levels with trusted people. If that's your neighbor who's recovered from covid, that's a great place to start. Sure. It's coming from a slightly different direction. I know that now every health system in the state I believe is now requiring vaccination. Most employees. Can you talk a little bit about the factors that went into that decision and why it's so important? Yeah, I mean, a number of factors went into it to be clear. I mean the first was our accumulation of of multiple people's comfort in the safety data. Number one, it is like I feel very comfortable recommending covid vaccines to almost everyone. And we have a robust exemption method for those who are the rare, Less than 1% who have reasons why they can't be vaccinated. Even in them, we now have pathways to help them be protected. You know, Number two, it's been quite clear that delta variant has has changed the landscape for us. Um, it has become again more aggressive as we've talked about. So there's a greater impetus for me to want to protect our own staff and I think it is our responsibility, frankly, as a health care community and as a health care provider, when someone comes at their most frail and they are being cared for by, by our team, I need to be able to project to them the greatest level of trust that they're not going to get sick because of their care here at Duke and I that that needs to be something that I would suggest patients bang the drum for. They should be advocating that their own healthcare workers are some of the first to be vaccinated. Mhm. More practically, it did rely on us having a guaranteed supply chain of vaccine and I think that was really important earlier beyond when many of us looked at the safety data and felt incredibly reassured by what we were seeing. We weren't in a position at that point to require it for staff because the supply chains were not as wide open as they now currently are. And I think every healthcare system now looks at that and says, you know, look, there's there's no reason for supply chain trouble that we can't do this. So I think you've then got safety for the staff, you've got safety for the staff, loved ones, safety for our patients. Um And it challenges are very important and powerful message that we are doing what we absolutely believe is the right thing and and to see all of the health care systems, including the V. A. Do that together and reach exactly the same conclusion was incredibly powerful. I think that sends the right message. Mhm. Absolutely, thank you. And before we wrap up, David, Mahon Fury, I'd like to come back to you. You spoken eloquently on this topic. I'd like to give you the chance just to remind people how important vaccination is for people's loved ones, uh the elderly, the young, the vulnerable those who can't get vaccinated for. Somebody who considers vaccination is just a personal freedom issue. Can you talk a little bit about the tremendous benefits to those we care about the most? Yeah, I think it's important for people to recognize that, you know, the reason for getting the vaccine isn't just to protect yourself is to protect others. You know, other family members and other people in the community. You might get infected and be a symptomatic or just have mild symptoms, but you could spread that virus to someone else who is more likely to experience severe illness and and die from Covid. So, it's very important to be aware of that and to be thinking about that when you're making a decision on whether or not to get the vaccine. Absolutely. Thank you. I think we will leave it there. Thank you everyone for joining us. Thanks to our panelists, David, Monte Fury and Camera Wolf for sharing your perspectives. I think one thing we've learned here is that people have questions about the vaccine and those, those questions have answers. So please share this as widely as you can. And if you know somebody who is vaccine hesitant, help them get the good answers to their questions. Next week, we'll be talking about the return to school and how that can be done safely. Who knows what we've changed between now and then. If you'd like to be notified about coming briefings, please email Duke news at Duke dot E D U. And if you're watching on Youtube, just like and subscribe. In the meantime, please stay well where I'm asked, get vaccinated and find good answers to vaccination questions for your friends and loved ones. Thank you so much for joining us and have a great day. Thank you, Greg. Thanks. Thanks. Dave. Yeah. Mhm.