So I want to welcome everyone tonight and especially thank you for taking some time to join us. I'm sure that you would rather be doing other things than listening to a talk about new therapies and IBD. And I'm absolutely certain that you are also experiencing COVID-fatigue. We have all experienced this incredible last 18 months. And when we thought that we couldn't take anymore, we had to learn more about the disease and we had to learn more about vaccinations.
I'm here to update you about that and to emphasize what I think is, overall, good news, and to empower you with the information you need to make sure you can be protected and protect those who are around you. So I'll go through, in the next 20 minutes or so, what we've learned about COVID-19 and IBD. It's, overall, very reassuring. Some of this, you may have heard before in these periodic updates we've done. And I guarantee that some of this is brand new because I've prepared this just for tonight. And it has some of the latest data on the vaccines in the IBD population.
So let me start by just reminding you some of those sobering statistics. Of course, we've had a pandemic in the world. And in the United States, there have been over 34 million cases documented and, unfortunately and tragically, 607,000 deaths. You can see the map of the US there, with what we call a heat map, demonstrating where COVID has occurred the most. And you can even see, if you're interested in American Samoa or the Virgin Islands, that's also part of this map. I also want to emphasize that we have made some incredible progress, as you are all quite aware. And that's probably why many of you have joined us tonight.
There are now 161.9 million people who are fully vaccinated. And that's, as of yesterday-- we have the latest data from the CDC-- that represents 48.8% of the total US population. As I'm sure many of you also know, that's regionally variable. There's a much greater number of people who are vaccinated in the urban settings, in the northern parts of the US, than there are in the rural areas and some of the less populated parts of the US. But the good news is that in the areas where we've seen the vaccine penetrate in people, adopt it, and obtain it, it's really change the natural history of the disease.
The death rate in non-metropolitan areas has exceeded the metropolitan areas. And it's thought to be directly related to access to the vaccine and to people getting vaccinated. So we want to educate you about what you should as a patient with IBD or as a family member or someone who cares for somebody who has IBD. And I also want to emphasize to and teach you about the variance to the COVID virus. So this graph on the left demonstrates the new cases of COVID reported in the United States, going all the way back to February 2020-- remember that it was just in early March that it was declared a global pandemic-- all the way up until the modern current day.
So as you look from left to right, you can see the timeline changing. And what we've put on top of this is when the different vaccines were approved or authorized. So Pfizer, Moderna, and the J&J vaccine have all been authorized by the FDA for what's called emergency use. That is determined by the fact that there's an emergency, which, clearly, the pandemic was, and that there's enough safety and efficacy data to get it on the market and to be used appropriately. It will achieve actual approval when they finish the longer term follow-up. But so far, that's immediately on track. And there has been no change or no unexpected findings related to safety and effectiveness.
As you look on the right, you can also see the deaths by day, that terrible, terrible time when there were over 2000 deaths per day, going on as a seven-day average, all the way down to now, where we've seen a much, much lower rate, thankfully. And we attribute this directly to the implementation of vaccination in the United States. So you've heard on the news, I'm sure, all about variants. Maybe you've heard people talking about the Delta variant or Delta. And I wanted to teach you a little bit more about this. So variants are essentially mutations in the virus. All viruses can undergo mutations that either lead to the virus not replicating-- which is a lethal mutation, therefore the virus just dies-- or mutations that lead to it being more infectious or having a survival advantage, in which case it then propagates and infects more hosts.
There are three categories of variants. There is variants of interest, variants of concern, and variants of high consequence. So if you look on the left there, you can see that. And they go from least infectious to most infectious. Now, this is a table we put together for tonight that actually tells you a little bit more about this variants because some of you, I'm sure, remember when we were talking about the UK variant, the South Africa variant, the Brazil variant. Well, now finally we started to get a little bit more organized. They're called the alpha, beta, Delta, gamma, epsilon, et cetera, variants.
And you can see the different dates of when they were first identified. So the Delta variant is the one that's of concern and has been spreading the most rapidly in the United States right now. And its origin was thought to come from India. So we go back to this slide, you can see the least infectious variants, which you probably haven't heard of at all because they don't seem to have much concern for us at all, and then variants of concern, the alpha and Delta. And thankfully, there have been no high-consequence variants that have been identified. What would that be? That might be variants that escape the vaccine protection, for example.
So it's important for you to know tonight that the Delta variant, and the alpha variant, as well as these least infectious variants are the ones that are all COVID by the available vaccines. I will also mentioned to you that if there is a variant that escapes the current vaccines, the technology used for the Pfizer and Moderna vaccine actually allows for adjusting, pretty rapidly, to address that variant. The equivalent for you to think about is that influenza, every year, undergoes some changes. And there are different variants of influenza. And what they do is they look to see what variants have appeared on the other side of the globe. And then they prepare the vaccines for the next season here.
So when we get the flu vaccine, it's actually been adjusted for the variants from the year before. And it's not known yet whether that's going to need to be something we do with the COVID vaccines. But that's something that is well described in influenza. And it's something that's obviously being studied and is of great interest. So how dangerous is the Delta variant? Well, Delta was initially 1% of COVID-19 cases in the week of April 10. It's not even visible on the bar graph on the right there. By the week of July 3-- not too long ago-- it was accounting for 57% of new COVID-19 cases. And it became the dominant variant in the United States within 12 weeks of getting here. That's how rapidly this spread.
As I mentioned to you already-- and I'll repeat several times-- the current vaccines protect you against the Delta variant. It's the people who are not vaccinated that are at highest risk for getting infected with Delta. And some of the data on the right show you how rapidly Delta spread. Look across the bottom, those are dates. And on the right, it's what's called a stacked bar chart. Delta is the dark orange. And you can see how that became the predominant version of COVID that's traveling throughout the US. And that's why they're seeing a resurgence in places throughout the United States that did not have vaccination.
The other thing I want to explain to you-- and I've actually given part of this lecture to our patients previously-- is this concept in infectious diseases called R-naught. R-naught-- which is the R0 symbol that you see there-- is the number of people that can be infected by one person who is infected with a particular transmissible disease. So if you look at the table on the right, you can see that the R-naught for measles is 12 to 18. That means for one person who has measles, they can infect between 12 and 18 more people around them. That's how infectious measles is.
In the early days of the sars-cov-2 COVID virus, the R-naught was calculated about two to three. But I want to point out to you, the final bullet point on the left there, the Delta variant is 60% more transmissible. And the R-naught is now thought to be close to seven. That means for one person infected with the Delta variant of sars-cov-2, they can infect up to seven people around them. It is a much more contagious variant of the virus. And therefore-- I want to drive home again-- we should be vaccinating everyone around us and it is recommended. And I'll get into what we know about from the IBD population in a few minutes.
If you look across this particular graph, you can see the relative increase in transmissibility of the different variants and, specifically, Delta, which is all the way on the right at yellow. And you can see how much more transmissible and infectious Delta variant has become compared to some of the other variants that are listed here on this slide. So as I mentioned to you, we've answered the question with some data and we're waiting for more. But the current Delta variant does not change the primary target of the available vaccines. The available vaccines target something called the spike protein on the coronavirus. And it's called a coronavirus because it looks like a sun under an electron micrograph. It has little spikes.
And that protein that make up those spikes has been the target of the vaccine, the target of our immune system, and how these vaccines work. It's good news to know that the Pfizer, Moderna, and Johnson & vaccines have all submitted data to the FDA and to the CDC demonstrating that their vaccines produce antibodies and protect people against the Delta variant. So if you're vaccinated, you're protected against Delta. I wanted to also update you, just so you know. The University of Chicago, which, in many ways, has led in its efforts to protect our patients, and to protect our community, and then also led in distributing vaccines, not just to the health care workers, but to our vulnerable patients and population, and then helping to vaccinate the first-responders in the population around us, all the different people who kept society running and safe.
And so the University announced, from the provost, that all people who work for the University of Chicago will be required to have a vaccination, unless they have some specific exceptions. And similarly, our dean and the president of our hospital announced very recently that everyone who works at the hospital will be required to have a vaccination. I share this with you because I wanted you to know that when you come to see all of us, we are taking this very seriously. And everyone you encounter will be vaccinated or have a very specific reason why they're not.
So moving on to IBD, what have we learned? Well, we've learned a number of things. And in fact, the IBD scientists and physicians, like Dr. Cohn, like me, and like our wonderful colleagues all over the world, have really led in many ways, in terms of showing how other subspecialty groups with chronic illnesses can protect their population and learn quickly what to do. We've learned that people with IBD do not have an increased risk of getting the sars-cov-2 infection, even when they're on all the therapies that you just heard Dr. Cohen discuss with you, with one exception, steroids.
We've also learned that people with IBD who get COVID, do not have different outcomes than the general population. They have the same risk factors. If you're overweight, if you have a chronic respiratory illness, if you have been on corticosteroids long-term, you are at higher risk for some problems if you got COVID. The general population, it's been well described that having multiple comorbid illnesses, like diabetes, and high blood pressure, and obesity put people at much higher risk for hospitalization, or even death from COVID. IBD patients have those same risks. They do not have any additional risks by virtue of having Crohn's, or colitis, or having an ostomy or having a J-pouch.
We do not have data yet on whether IBD patients are going to be any different than the general population in the risk of developing the long-haul problems that you may have heard about, where people have persistent problems, even with mild COVID, that continue to plague them, fatigue and other generalized difficulties. We don't think our IBD population will be at any increased risk than the general population. But the next time someone tells you that they would rather just have a mild case of COVID then get vaccinated, you should have some conversation about the fact that that's not necessarily protection against long-term problems from the illness, not to mention that they're going to put other people at risk.
We've learned that the therapies we prescribe and use to treat IBD have no increased risk for severe COVID, unless you're on steroids at doses of 20 milligrams or higher. And obviously, we try not to use those in the majority of our patients with IBD. There is an international registry. It's voluntary. But it's collected a huge number of patients now that has described the outcomes of COVID-19 in people with IBD from all over the world. We've participated in this registry from the University of Chicago. A number of our patients are in that database. And they've now done a number of analyses over time.
And you can see, for those of you who are a little more statistically-minded, I wanted to point out to what's called the adjusted odds ratio on the right, which is showing you the relative risk of having problems with COVID based on therapies or other diseases that people may have. Having IBD does not increase your risk for those bad outcomes. Also of interest, for those who've been paying attention, the salicylate therapies, the mesalamine drugs-- that's Asacol, and Lialda, and Balsalazide, and Apriso, and Pantasa-- they are not associated with any risks for bad outcomes from COVID.
In the early days, there was some confounding in interpretation. And we weren't sure about that, which didn't make any sense because these aren't even immune drugs. And now with the proper studies, not just in this international database, but in several other studies, we've learned that 5-ASA therapies are not putting people at increased risk. Very interestingly, if you look at the last line on that table, being on a biological therapy-- and most of the time, it was anti-TNF, drugs Remicade, Humira, Cimzia, Simponi-- was protective against having severe COVID. And what we learned is that the severe COVID was an overactive inflammatory response. And those drugs, we think, are protecting people from having the worst outcomes in IBD and from COVID. So there's some very good information about your treatments. You're definitely not at increased risk for bad outcomes with the treatments for IBD.
Now, there have been some confusing articles in the mainstream media. The media have published articles that conflate, and confound, and confuse. There have been articles in the New York Times, The Washington Post, CNN, that have been picked up related to some of the work that's been done in organ transplant patients, where they have much more immune suppression and a different type of immune suppression than what we use in IBD. And occasionally, they've misinterpreted that and expanded it across all immune-mediated conditions. So they lump in IBD, or rheumatoid arthritis, or psoriasis with people who have had organ transplants or who are receiving chemotherapy for cancer or bone marrow transplants. That is not true.
And in fact, these articles were something that prompted letters to the editor of both the New York Times and The Washington Post. I wrote with the president and CEO of the Crohn's and Colitis Foundation and then, subsequently, also for those who are following me on Twitter, a lot of work to clarify and make sure people understand that the articles made a mistake calling IBD patients immune-compromised and lumping them with organ transplant patients. In fact, we have good data to show that, actually, the patients who are on these therapies have a normal response to the vaccines and are protected. And I'll show you a little bit of those data as I wrap up here.
We came out with some international guidance. And it is recommended that all patients with IBD should be vaccinated. And you should get it as soon as possible. And it doesn't matter-- you shouldn't time it differently with the dosing of your IBD therapies. You can do it on the same day if you want. But you should work to get vaccinated. And I think most of you on this call have already done so. So is the vaccine effective in people with IBD and how do you measure it? Well, there's a few things to remember. The first thing is what's called immunogenicity, which is the vaccine's ability to induce an immune response against the virus. So you may also have heard the term immunogenicity because we use that term to describe when patients develop antibodies against their biological therapies. It's the same concept. It's your body's ability to develop antibodies against a protein.
Titers refers to the amount of antibodies that you make. And you can measure titers against specific targets. A neutralization titer is the right titer that is associated with eradicating something in your body. In this case, we're talking about sars-cov-2. But remember that titers are only one part of your immune system and what gives you immunity after you've been vaccinated. It's only one part because there's also a separate cellular immunity that you gain from vaccines that is not measured through a commercial test that we can order. And the longer you have a vaccine, some vaccines have an attrition over time, which is what the graph on the right shows you.
And so it's possible that you can have waning of protective immunity over time, which is what people are worried about. And that's why people ask, should I get a booster? The immune response to COVID-19 vaccines is demonstrated on this graph here. And there are two things to keep in mind. The first one is the gray curve, which is the Johnson & Johnson single-dose vaccine. The second is the red curve, which represents the two-dose vaccines, which is Pfizer and Moderna in the United States, AstraZeneca, which is available mostly in Europe. And you'll see that when you get a two-dose vaccine, there's a primary immune response when you get the first dose.
What the second dose does is it triggers what's called a secondary immune response and better immune memory, which is how your body remembers how to respond over time. That's the whole concept between a two-dose vaccine. So while the one dose vaccine offers some convenience, it also has a greater likelihood of loss of response over time and is not as strong as a two-dose vaccine. Now, when you measure titers against these vaccines, there are two different kinds of titers you can measure. One is called the nucleo capsid titer, that means, did you have an actual infection with the virus and develop COVID? That particular titer is specific to you, having been infected.
The titer we look for is the spike protein titer. And remember that I already told you that the vaccines target the spike protein. So if we're going to measure your titers, we look for a titer against spike proteins. If you've had an infection to COVID-- I've heard people say to me, I don't need to be vaccinated, I've had COVID-- well, we've learned that, actually, the native infection, especially in healthy people, doesn't produce durable immunity. So if you think you're protected because you've had COVID, you should think again. The vaccine is much, much more effective than having had COVID.
And you might be interested to know if you've had COVID when you get your first dose of vaccine, that's like the second hit. That's like the two-dose vaccine. The first dose was you getting infected, the second one is what induces more of a sustained memory immune response. I hope that makes sense. So what we've learned about in a number of papers that are now coming-- this paper isn't even published yet. And it's called a preprint. So we'll take it with a grain of salt. But they looked at all patients with different immune conditions, from people with HIV, to cancer, to organ transplants, to, as you see, IBD.
And what they found across all these different groups was that when you use the two-dose vaccines, Moderna or Pfizer, there was no difference in the vaccine efficacy, as measured by the production of antibodies against the virus. Whether you had the condition or not, specifically, IBD-- as you see highlighted with the red box-- there was no difference. 87% of the IBD patients in this study developed protective immunity. And we believe that it's actually at least that high in the rest of our patients.
How safe are the COVID vaccines for people with IBD? Well, let's start with safety of the vaccines, overall. They're now been so many people vaccinated that we have, by shear force of numbers, we know that there are not new signals to be worried about. We would expect to see things if there was something that had been somehow missed in the early studies. I want to remind everybody, as well, that the messenger RNA vaccination mechanism-- the Pfizer and Moderna approach to vaccines-- has been in development since 2000 to 2003. Some people think it was rushed to the market. That isn't true. They started working on this after the original SARS, which happened all the way back in the early part of the 2000s.
So they rushed to get that done. And they were able to do these massive studies quickly because so many people were infected. But the data, the quality, the regulatory pathway, the emergency-use authorization, is the same. There were no shortcuts here. And for those who continue to say, I want to see what else happens, well, you have the 161 million people in the US, we have study, after study, after study. And what we've seen repeatedly is that these are safe vaccinations and they are effective. Question that always comes up, is this going to stimulate my IBD to flare.
Well, there the answer is no. It's a different type of your immune response. So that's the physiologic explanation. But we actually have data now. A study of 246 patients with IBD who received both doses of the two-dose vaccine showed no difference in their adverse events, including relapses of their IBD. And we've been following all of our patients here. And we have not been able to show that the vaccine, in any way, triggers a relapse of the IBD. Should patients with IBD get a booster? This is one of the most common questions we're hearing and people are asking.
So currently, there's not a recommendation for an additional dose of vaccine. There are a couple of exceptions that I'm going to tell you about. So remember that, number one, the FDA hasn't even approved a booster or authorized a booster. And although we've heard from Pfizer and from data in Israel that they're suggesting a booster might be needed, that hasn't been actually made part of the recommendations from the CDC or the FDA yet. But more importantly for all of you, you want to know whether we still think it should be done. Well, we're not sure yet whether this is going to be needed. And I want to emphasize to that measuring your titers won't tell us whether you're still protected or not.
An argument could be made that, why not give you a booster, because what's the harm, given how safe we think the vaccine is? I think that that's not necessarily a bad argument, to be very honest with everybody tonight. But I don't think we can, wholesale, start telling everyone to get a booster right now. I guarantee you that if we learn that there's waning protection and that boosters are needed, we're going to let you know ASAP. The people who got vaccinated first-- which were folks in nursing homes, and first-responders, and health care workers-- would be the first who are going to have any kind of waning of their immunity.
I'll tell you, though, there i a really intriguing study where they had stored blood from people who lived through the 1918 pandemic. And they were able to detect protective immunity in the blood samples from those patients 100 years after they had been exposed to the pandemic back then. So it's entirely likely that the vaccine will help protect us longer than people are worried about. But we need to know more. So I'm being completely honest with you. We don't have all the answers to that yet. We are currently not recommending that you get a third dose. There are a couple exceptions that I might tell you about.
So if you're on this call tonight, you haven't been vaccinated, now you're saying, OK, I understand, I'd like to get vaccinated. My recommendation would be to get the two-dose vaccine for the reasons that I've shared with you, that would be Pfizer or Moderna So in this grid that I've created for you, if you have IBD, and you've not been previously infected or had COVID, get the two-dose vaccines. If you don't have IBD, you have three options Pfizer, Moderna, and I think that the Johnson & Johnson vaccine is completely reasonable. Why am I not recommending a one-dose Johnson & Johnson vaccine if you have IBD? Well, because I think that want to get the durable immunity. And even if there's a slight decrease in your protection with the therapies you're on, getting a second dose overcomes it.
We have data from the UK-- in a very important study led by Nick Kennedy and colleagues at Exeter University with multiple centers involved-- that having a two-dose vaccine overcomes anything that you might see from the therapies you're on, otherwise. If you've had a prior COVID infection, remember, I told you that's your first exposure. So then you can get the one-dose Johnson & Johnson and it'll be like a second dose or the two-dose Pfizer and Mordern's. So this is how I've tried to simplify this for you. Notice that I'm not saying you should get a booster with any of these yet.
What if you have IBD, no prior COVID infection, and you're already vaccinated with the J & J? Well, to be honest with you, this is the one exception where I might say go get a Pfizer or Moderna vaccine so you get the second exposure. You can mix and match these, by the way. I have no data to tell you that. That's why the title here clearly points out to you that this is my opinion. What's the update about kids? This is my last topic, really, and then I'll wrap. We have data now with Pfizer that kids 12 and older can get the vaccine, that it's safe, and it's effective. It's recommended.
And there are ongoing vaccines for kids under age 12. The data will be available in September, but not early enough for the FDA to rule on it before school starts, unfortunately. So you're left with, unfortunately, wanting to make sure you protect everyone who's around the children and to do our best to make sure that our kids stay well, and protected, and that when the vaccines are studied and available for them, to vaccinate the kids as well. If you are vaccinated, can you still get sick? Well, you can. But I want to point out to you that if you're vaccinated and you get COVID, which can happen, rarely, but it does, it will be mild. And we've seen practically zero hospitalizations and, thankfully, no deaths in the vaccinated individuals who get COVID despite being vaccinated.
So there's a lot of research going into this. We have data to support this. And we're very comfortable that although you can still get the virus and be infected, you won't have severe COVID and, thankfully, you won't die. So it is very important to understand that. Should patients who are vaccinated wear masks indoors? Well, let me start by saying that if you're vaccinated, I don't think you need masks outdoors. And I hope that's reassuring to all of you. Should you wear them indoors? Well, the CDC says you do not need to do so if you're vaccinated. I'll tell you that it depends where you live and who you're with.
If you're in parts of the United States where there's a high prevalence of Delta and people who are unvaccinated, then you probably should wear a mask. Why take a chance of being infected? Even if it's going to be mild COVID, who wants to get that? If you're with people you know and they're vaccinated, then I think you're fine to not be wearing a mask indoors. If you're going to a crowded place where you don't know who everybody is, it's your choice to wear a mask or not. But I would suggest that we're still in a place, until we see Delta quiet down and we know what else is going on, where you just want to avoid getting a mild infection. You are protected, but I would say wearing a mask indoors is more practical. It's nothing to do with having IBD. It's what I would tell my parents. It's what I tell my friends. It's what I tell everybody.
Can you transmit the virus to others after you've been vaccinated? Well, there are limited data. But in general, it's thought that you can, but it's a very small likelihood because the virus can't replicate in you. You can have the virus, you can test positive for COVID, but it doesn't produce at a volume that's enough that you will transmit it to others. So in general, the answer is, yes, it can happen, but it usually doesn't. So I've covered a lot. I'm sure there's a gazillion questions, but maybe Dr. Cohen has been handling all of them. If you have IBD, you should be getting vaccinated. There's no reason having IBD should prevent you from getting vaccinated.
The vaccines authorized for use in the US are safe and effective with patients who have IBD, and despite being on therapies. This has all been looked at now in many different ways. The Delta variant is highly infectious and transmitted to unvaccinated individuals. I've been telling my patients who aren't vaccinated that they're going to end up getting COVID because of Delta and they need to get vaccinated. Although unproven for those who received the J&J vaccine, you heard me suggest that you should get a second dose. I think that's reasonable. And for those who've received the two-dose vaccines, I hope this is reassuring for you to know you're protected. You're going to be OK.
The benefit of measuring titers or receiving a third dose is unclear. And I'd like you to join one of the available trials to help figure it out. We have three studies around the US that are available. They're all available for you to join, even from where you are here in the Chicago area or wherever you're logging in. One is called Prevent COVID, run by our colleagues at the University of North Carolina. One is called Corale-V IBD, which is run out of Cedars Sinai in Los Angeles. And the third one is called Icarus, which is run out of the Mount Sinai Medical Center in New York.
If you want to be part of our study at the University of Chicago, we're looking at how long vaccination lasts. And we're looking at other outcomes in all of our IBD patients. We would ask that you email so that you can be part of this. If you've already been vaccinated, or if you're planning to get vaccinated, or if you're not vaccinated, you're all welcome to be part of this important study. And it requires three blood draws that will be done at your convenience. The email address is there for you, covidvaccine.ibd@lists.uchicago.edu.
So I know that's a lot of information. Hopefully, some of it was new, and helpful, and reassuring. And now I'm going to let Dr. Cohen moderate a bit and see what kinds of questions came in. Thank you very much.