Avian Flu Outbreak and Preventing the Next Pandemic

Wednesday, May 29, 2024

Chief Executive Officer, The Pandemic Prevention Institute, The Rockefeller Foundation

Jennifer Nuzzo

Senior Fellow for Global Health, Council on Foreign Relations


Vice President for National Program and Outreach, Council on Foreign Relations

Jennifer Nuzzo, senior fellow senior fellow for global health at CFR, discusses the spread of the avian influenza in poultry and dairy cows in the United States and risks that zoonotic diseases pose to human populations. Rick Bright, former chief executive officer of the Pandemic Prevention Institute at the Rockefeller Foundation, discusses measures being taken to mitigate the spread of avian influenza and U.S. preparedness for future pandemics. A question-and-answer session follow their opening remarks.


FASKIANOS: Thank you. Welcome to the Council on Foreign Relations State and Local Officials Webinar Series. I’m Irina Faskianos, vice president of the National Program and Outreach here at CFR.

CFR is an independent and nonpartisan membership organization, think tank, and publisher focused on U.S. foreign policy. CFR is also the publisher of Foreign Affairs magazine. As always, CFR takes no institutional positions on matters of policy. 

Through our State and Local Officials Initiative, CFR serves as a resource on international issues affecting the priorities and agendas of state and local governments by providing analysis on a wide range of policy topics. We appreciate you taking the time to be with us for this on-the-record discussion.
We’re delighted to have over 300 participants from forty-seven U.S. states and territories. I want to remind everyone that the webinar is on the record, video and transcript will be posted on our website after the fact at CFR.org, and we will circulate it as well. 

We are pleased to have Dr. Jennifer Nuzzo and Dr. Rick Bright with us today to lead the discussion on “Avian Flu Outbreak and Preventing the Next Pandemic.” I will share a few highlights from their distinguished bios.

Dr. Jennifer Nuzzo is a senior fellow for global health at the Council on Foreign Relations, where her work focuses on global health security, public health preparedness and response, and health systems resilience. She is a professor of epidemiology and the inaugural director of the Pandemic Center at Brown University’s School of Public Health. And she also directs the Outbreak Observatory, which conducts operational research to improve outbreak preparedness and response. 

Dr. Rick Bright is the CEO and founder of Bright Global Health and works as a consultant for pandemic preparedness. He previously served as head of the Pandemic Prevention Institute at the Rockefeller Foundation. He was also the director of the Biomedical Advanced Research and Development Authority, known as BARDA, and the deputy assistant secretary for preparedness and response in the U.S. Department of Health and Human Services. And he was a member of the Biden-Harris Transition Advisory Board on COVID-19. 

So thank you both for being with us today. I think we’ll begin with you, Dr. Nuzzo. If you can talk about the current status of the avian flu outbreak, the symptoms, risks it poses to animal and human populations, especially those working in food processing plants.

NUZZO: Thank you so much, Irina. I really appreciate the introduction and the opportunity to participate in this session. I wish we didn’t have to talk about H5N1. H5N1 is an influenza A virus, we are—particularly called a highly pathogenic avian influenza A virus. It predominantly infects birds, but humans that have—humans have been infected, particularly those who have had contact with infected animals. And while we’re having this webinar now and we’re talking about this now, and it’s been in the news a lot now, I think it’s really important to understand that this is not a new virus. It’s actually one that we’ve been tracking for quite some time. 

In fact, this virus was first recognized in the late ’90s, when it was detected in geese. Then in 1997, it caused a fairly large outbreak among humans. About eighteen cases were identified in Hong Kong, and of these six died. This was enough to prompt, you know, massive concern, you know, big chicken culling operations and attention on live markets, which thankfully sort of, you know, contained that human outbreak. But it didn’t eliminate the virus. In fact, the virus continued to circulate in birds, and ultimately spread to domesticated ducks. And this is thought to have then kind of contributed to the reemergence of the virus in humans in 2003, late 2003-early 2004, when we started to see outbreaks in a number of neighboring countries in Asia. About eight initially and then we saw the virus spread to a number of other countries as well. 

Since this virus was first identified till now there have been about 900—just under 900 known human cases. But nearly half of these have died. And this statistic, while incredibly imprecise, is enough to be alarming, because typically when we, you know, find cases and we calculate the percentage of those who died, 50 percent is really—you know, really, really ranks up there in terms of severity. It certainly is on track to put, you know, H5N1 to be a much deadlier virus in terms of that percentage than, you know, the virus that caused the COVID-19 pandemic, certainly more so than seasonal influenza. So there’s a reason why we’ve been worrying about this virus for a number of decades. 

As I said, the majority of these cases are known to have had exposures with sick animals. But there is some evidence that there may have been human—very limited human-to-human transmission. You know, people who have gotten it that didn’t quite know what they were exposed to. There was actually a study that looked back at that 1997 outbreak in Hong Kong and found evidence that healthcare workers who cared for some of those sick patients may have been infected, possibly without symptoms—which is concerning. But nonetheless, we haven’t seen any evidence of sustained transmission between humans. 

And that’s fortunate because were we to see evidence of that, were we to see that, you know, multiple generations of people—meaning like, one person can give it to the next who could give it to the next—were we to see evidence of that, that would truly signify, I think, the beginning of a new pandemic, or perhaps the start of one, were we not able to contain it swiftly. Remember, this is—this is a new virus. You know, nearly—hardly anyone has actually gotten this virus. And so that that immune—that naive immune state, meaning we haven’t had, you know, background immunity to it, would make us likely all susceptible to this virus. So again, were are we to see evidence of sustained human-to-human transmission, that would very much signify the start of a pandemic. 

Now, that hasn’t happened yet. And that is quite fortunate. But nonetheless, the worry about H5N1 persists. You know, I would say this virus has continued to circulate on the planet and hasn’t gone away, but I think some of the attention around the virus really, you know, began to wane a bit. In part because the majority of the human cases that we have seen to date really occurred between 2003 to 2015. And then there was a relative lull in the occurrence of human cases. And why that is isn’t quite clear. But that, combined with the occurrence of other health emergencies—including a pandemic caused by a completely different influenza virus, one that occurred in 2009—that was due to the H1N1 virus, not H5N1—you know, I think it really helped to, unfortunately, distract us from the threat that H5N1 poses.

I would say that all kind of came to a screeching halt, that relative quiet and that relative distraction that people, you know, who kind of track these things were experiencing, really about a couple of years ago when we started to see much more viral activity from this virus. Started to see a massive kind of geographic expansion, the virus turning up in parts of the world that we typically hadn’t seen it, and also a massive species expansion. Meaning it was starting to not just affect chickens, and ducks, and other wild birds, but many other species—including mammals. And, you know, for me, that’s when I started getting worried because, you know, mammals are a lot more like humans than chickens are. And so that, you know, increases concerns that perhaps this virus is getting increasingly better at infecting things that are more like humans than chickens are. 

That backdrop had been happening. And then really I think concern ratcheted up even higher when in March we heard about an outbreak on dairy farms—dairy cattle farms in Texas. That was surprising. One, because we hadn’t previously seen H5N1 in cows before. But also, influenza A infections have not regularly been reported in cows. And so that, you know, was just unexpected from a scientific perspective. But from a public health perspective it was concerning because, again, yet another mammal that this virus was capable of infecting. But in this case, it’s a mammal that humans have very close contact with. And so that raises concerns that humans would be, you know, exposed to—you know, humans would be exposed to this virus because they are exposed to these mammals quite closely. 

Those concerns were realized when then we saw, you know, a case of H5N1 in a dairy worker. And then subsequently we have now found a second case in a dairy worker. This is quite concerning. Fortunately, these two infections were relatively mild. The dairy workers didn’t require hospitalization. They experienced eye inflammation, conjunctivitis. They didn’t have a positive respiratory specimen, which, you know, I think is an important finding. But it does raise the possibility that this virus is starting to do things that we don’t want it to do. There have also been just anecdotal reports from vets who are working on the farms that other workers may have experienced symptoms too. So I think reason to believe that these two cases may not represent the totality of dairy workers who have been infected, and certainly don’t necessarily mean they will be the only two dairy workers infected.

Since then, of course, there have been more news developments. You know, finding of viral genetic material in pasteurized milk. Not entirely surprising that we would find it, but certainly concerning given the number of positive samples found, which suggests that this virus may be on more farms than our surveillance is telling us. Also recently, last week, there was a report that they found the virus in muscle tissue from a specimen taken at a slaughterhouse. So, again, concerning that this—concerning evidence that this virus may have a much larger geographic footprint than just the amount of testing that’s happening on farms would suggest. 

And that’s really, I think, where I just want to maybe call our attention to. You know, the biggest worry that I have right now is really in protecting farmworkers. We have ample evidence right now to know that this virus, while it is not yet a pandemic threat—it may not cause a pandemic, we don’t know for sure, we have reasons to be worried, we don’t know for sure. But what we do know is that farmworkers who are exposed to this virus in the course of their occupation can get infected. And we know historically that this virus has not produced—you know, has not typically been a mild virus. And so that really, I think, creates an urgent public health situation where we should be acting to protect these farmworkers. 

Unfortunately, the level of testing that we’re doing right now is really not sufficient to allow us to protect farmworkers. You know, the testing that USDA is requiring is quite limited. They recently put into place a new policy that people are calling sort of the test to move policy. If lactating dairy cows are going to be moved across state lines, it is required that cows from that herd be tested. But the farmers can basically pick the number of cows that get tested. There’s a maximum number that’s established. So, as you can imagine, that’s not quite comprehensive enough to find all of the infected—all of the cattle that may be infected. Other than that, testing is largely voluntary. It’s limited to cows with symptoms. It does not include beef cattle. And so you can imagine that there are lots of holes in our abilities to figure out which farms have the virus and which don’t.

Which makes it hard to protect the workers on those farms. The testing that’s happening is not happening on the farms themselves. It has to be sent to a lab.

So the test results aren’t timely enough to protect workers. So there’s just a lot of ways where exposures can happen that we wouldn’t know about, which, again, makes it hard to make sure that the workers can get, you know, access to antivirals that could protect them if they’re—you know, protect them from severe illness if they are infected. It also makes it hard to stay ahead of this virus and to understand what might be next for it. 

So that’s the area that I think I’m most worried about right now, is, again, making sure these farmworkers have the protection they need. In my view, enhanced testing is really critical to that. I also think we need, you know, to make sure there’s greater use of protective equipment, particularly eye protection. I think we should also be talking about using vaccines and expanding access to therapeutics. But I know Rick will have a lot to say about that, so I will let him address that. 

But I just want to sort of end with this overall notion that this virus has had a lot of ups and downs in the twenty-plus years that we have been tracking it. I will say I am much more worried now than I have been in those past twenty years. And I don’t think we should be waiting for it to be obvious that this represents a broader public health threat for us to act. We should be trying to get ahead of this virus so that it doesn’t become the catastrophe that we fear that it could be. We have tools, but we need to make much more proactive use of those tools. And I know Rick will have a lot to say about that. But I’m grateful he’s here to enlighten us on that front. 

FASKIANOS: Wonderful. Thank you so much, Jennifer. 

And, Rick, over to you.

BRIGHT: Well, great. Thank you for hosting this, Irina. And actually, I could never do a better job than Jennifer laying out that background. You know, I started my post—my graduate student work in 1997 with the spillover of H5N1 in Hong Kong from those birds into humans. And so for twenty-seven years, I’ll age myself, twenty-seven years I’ve been like Detective Colombo with an open—file open case tracking this virus. And we’ve seen it come. We’ve seen it kind of abate. And we’ve seen it come. We’ve seen a kind of abate. And I think at some points we fool ourselves into thinking if it’s abated this many times over history, then maybe we shouldn’t worry so much about it. 

And so I tell people that, you know, we are more prepared for an influenza pandemic than for any other pathogen pandemic, probably, that we know of. And that is why I’m concerned, is because of that preparedness. The twenty-something years of investment in understanding the virus, understanding the vaccines, and how they work, their challenges, and antiviral drugs and diagnostics—therein gives me the concern, knowing those vulnerabilities. And that some might be easily misled into thinking we’re ready, that we have this under control. You know, and so because of what we know about this virus, we know it is a shapeshifter. We know it can rapidly change. We know it can jump to different hosts and different species rapidly, and change, and evolve. Part of that is the nature of influenza viruses. They are these negative-stranded RNA viruses, so when they replicate themselves it’s kind of sloppy and they introduce these mutations. And those mutations can help it be more lethal, or adapt, or spread to humans and other hosts. 

Sometimes because the genetic makeup of the virus is fragmented, there’s all these segments inside that virus, you can have two viruses infect a person, or an animal, or a seasonal virus and the H5N1 virus. And they’ll recombine and reassort. And you’ll have this virus that comes out with some of the best or worst of all worlds. And so we know the tricks of this virus. And because of that, we’ve been somewhat placated that we kind of think is manageable in the bird population. When we see a jump from the wild birds—ducks, geese—that’s sort of this reservoir. We’re never going to annihilate it from wild ducks. But when we see it jump to birds in the past, domestic poultry, we basically wipe out the flock and decontaminate the area. And that seems to abate it somewhat. 

Never in history have we seen this virus spread in such a sustained way to so many different mammalian species. And that is a concern I want to echo that Jennifer’s put forth. Also want to say that this is such a rapidly evolving situation that anything we see today or know today can change tomorrow. It can change very, very quickly because of the nature of the virus. And also, I think, because of the complacency that we might also see now, because we think we have it ready. So some of the things we’ve invested in, we’ve invested probably $10 billion at the federal level. I was the head of the influenza division at BARDA before I became the director of BARDA. And through the many—or, ten years I was there, $10 billion in designing vaccines, changing vaccines, trying to transition from a 1940s technology of egg-based vaccines, to cell-based, to recombinant-based vaccines that could probably be designed and manufactured faster than egg-based vaccines. We’ve invested in antiviral drugs and we’ve invested in diagnostics. 

So I’m going to tell you that that’s good news, because we have a lot of experience and a lot of expertise. The bad news is 90 percent of our global capacity of making influenza vaccines are still in 1940s technology of eggs. For the United States supply alone, it would take 900,000 eggs going into a facility every single day for six months without fail just to make a supply of H5N1 vaccine for the United States. In parallel, we would have to make a new—a chemical component of that vaccine called an adjuvant. And the adjuvant would have to be added to that vaccine. And we only have two manufacturers of that adjuvant for the world. 

Globally, we only have about the capability, capacity to make four billion doses of egg-based pandemic flu vaccine in a year’s time. And Bill Gates and the Gates Foundation, about 2017 I think it was—2016-2017—did a model a transmission model showing that if we were to have a virus such as the H5N1 influenza virus that transmitted efficiently between people and cause a severe illness and death, in a six month period of time we could see ten million deaths in the United—around the world—around the world. And so that tells you that we have to move swiftly. That tells you 90 percent of our capacity is based on a 1940s technology. 

We did invest in a cell-based vaccine approach. We have one manufacturer in the United States, Seqirus, that can make a limited supply of cell-based influenza vaccines. And we have three other manufacturers globally, so four total around the world that can make a cell-based vaccine. So that would come in handy, primarily, if an H5N1, which is a bird flu virus, were to infect the chicken flocks that are required to lay those eggs that are needed for that vaccine. Imagine how vulnerable that supply chain is. Those are fertilized eggs, by the way. So those are embryonated. Those aren’t just eggs we can go to the grocery store and buy. And they’re very select. 

So we have this candidate vaccine virus, that CDC mentions, the CVV, which is a starting material for an H5N1 that was made from a virus in 2020. And we could put that in our limited egg capacity. And what we learned from the 2009 H1N1 pandemic, that many of you were probably involved in, that we overestimated the productivity of that vaccine capacity. At the federal level, we were promising the country that we would have 120 million doses of vaccine six to nine months out, by October of 2009. And because the virus did not grow well, that candidate vaccine virus, CVV, didn’t grow well in eggs. At the end of October, we only had seventeen million doses for the United States, mostly for the world. And that came after two major waves of the virus in 2009. So it tells you we need a lot—to do a lot on the vaccine front. 

On the antiviral front, we really have two classes of antiviral drugs. We had three in 2003 and 2004. The adamantane drugs, the M2 blockers, many of you might be familiar with. I actually published a paper in The Lancet showing that 100 percent of the viruses circulating, seasonal influenza, were resistant to that drug. We were using that drug for many years thinking it was working and saving our older population when it wasn’t, because no one did the testing. We weren’t doing the right surveillance and monitoring for drug resistance. So we’ve sort of learned our lesson. And we track the neuraminidase inhibitors—so Tamiflu, and Relenza, also Tamivir and Zanamivir. 

And in 2008, we learned that every seasonal virus circulating was completely resistant to Tamiflu. We were lucky with the 2009 H1N1 pandemic strain, because it reintroduced a sensitive neuraminidase in that virus that circulated for the pandemic. Therefore, also Tamivir or Tamiflu was effective. But it was only three months into that pandemic we started seeing resistant viruses to also Tamivir or Tamiflu. So it shows you how vulnerable we are to that particular antiviral drug. So we invested in another one called Baloxavir or Zofluza. It works in a different mechanism and a different part of the influenza virus. In our stockpile, we have about 600,000 doses of that. And we have about 75 or 80 million doses of Tamiflu. But that Tamiflu drug was purchased in 2005, and 2006, and 2007, some of it. So it’s past its expiry date. 

And I imagine that once we were in a full-blown response and we started shipping our limited supplies of Tamiflu from the stockpile to the states, we’ll see what we saw in 2022 in the influenza season, when we had spot shortages, and they started shipping out the oldest material from our stockpile. Many of the states didn’t accept it. It was hard to describe to people why they were getting a drug that said it expired in 2007 or in 2010. So we have a number of things to do in the antiviral drugs.

In the testing space and diagnostics, we don’t have a test that will tell a clinician that a patient has H5N1. We have rapid antigen tests and some other lab tests that would tell you it’s influenza A or influenza B. But we don’t have one that says, this is H5N1. We need to have a test that we can really rapidly detect when a person is infected with this virus, because the antivirals that we have really only work if you use them in the first thirty-six to forty-eight hours of symptoms when you’re infected with this virus. And we also know from H5N1 viruses, traditionally it took about twelve to fifteen times the dose of Tamiflu to inhibit H5N1 viruses, compared to a seasonal H1N1 virus. So the limited supply we have would be cut by maybe fifteenfold. 

So when you hear messages that we’re ready, we have this, I want you to really think about how ready are we. And therefore, it leads to the question, what can we be doing now to be better prepared? And that would be accelerated development of tests that can be in the hands of people and clinicians at point of care that could distinguish rapidly an H5 infection. It would be to accelerate the procurement of stockpiles at the federal level, and maybe the state level even. That’s a diversified stockpile that might be as part Tamiflu, might be part Zofluza, or Baloxavir. So we have at least options, if we saw resistance developing to the other. And, of course, we need to think about vaccination and how we can invest in technologies that would scale more rapidly so we can have more doses quickly that are independent of eggs. I talked about the recombinant-based vaccine that we built with protein sciences. That technology has been acquired by Sanofi Pasteur, and basically offshored and moved to—out of the U.S. So in the U.S. we don’t have that capability any longer. 

We do have a stockpile, a surge capacity of eggs. We can surge to from 600,000 to 900,000 eggs a day pretty rapidly. But I’ve already described the vulnerabilities. So I think it goes back to, number one, what you’re thinking is, how do I tell people now—or, how do I reduce the chances of getting infected with this virus, while we figure out some of this other stuff that may not be directly in your hands? And, as Jennifer noted, I mean, the greatest risk are to those who are in close contact to the virus. That means those who are in close contact to infected animals. That might be an infected dairy cow. Might be infected cats, or birds, or raccoons, or skunks, or alpacas now. So if you see a sick animal, just stay away from it. Call animal control and let them handle the sick animal or dead animal. Avoiding contact with that is going to help reduce your risk. 

Of course, we know that the milk coming from infected cows has very high titers of H5N1 virus in it, if it’s not pasteurized. So raw milk has super high virus titers, some of the highest titers of virus I’ve seen in any substrate.

When we have this quantitative PCR analysis and you get a three, that means there’s a lot of virus in that milk. So discouraging raw milk consumption and raw meat, or undercooked meat, from potentially infected animals is primarily important. Keeping a distance from infected animals, staying off and the dairy farms, et cetera. If you have people in your states and areas that work on dairy farms, the CDC has put out some really important guidance on how to protect themselves working on those farms. 

I know it looks uncomfortable. I can’t imagine working on a dairy farm and having to really gown up. The instructions that came out today look almost as if they’re protecting themselves from an Ebola outbreak, other than the hood. But they’re—the head-to-toe clothing and protection, head covers, the right type of respirators, eye covers, gloves—this is really important if they are working in environments that have infected animals, because you don’t want them to be the test cased that this virus infects and then have further opportunity for adaptation in the human population. But those are primarily simple things to do, sometimes complex to implement. 

But right now, the general population, if they can stay away from infected animals and products, they’re pretty safe. But I do think it’s a ticking clock. I do think we’re about to hit midnight. I’ve never seen this virus take hold in mammals, so far—so broadly distributed in such a sustained way. And we are not doing the testing. We have not done serology studies. And maybe you can do that at the state level to start getting a baseline of human immunology, who is exposed, what level exposure there is among the general population, high risk individuals. Imagine if a lot of the infected dairy cows are going to slaughter, which they are, and if there is infected meat product going to your fast-food restaurants where a lot of this dairy cow meat goes. It goes into pink slime and it goes into fast food burgers, a lot of it. 

And, of course, the FDA says if you cook that meat to 140 and 160 degrees it removes the virus. However, if you handle that meat in the process of it being cooked, you’re at high risk. So it’s really important to think about the entire chain of transmission, potential exposure, and protecting all people on the farm all the way through the market to the slaughterhouse and processing plants. So, I’ll stop there. Again, to remind you, this is an evolving situation. What we know today will change tomorrow. More crops—more animals are exposed. So pay attention.

FASKIANOS: Thank you very much for that. And now we’re going to go to all of your questions and comments. Please use this forum to share best practices as well as what you’re doing in your own communities.

(Gives queuing instructions.)

And so with that, I’m going to go first to Renee Yarbough-Williams, who is the chief of staff and the office of Maryland Delaware (sic; Delegate) Cheryl Pasteur. Basically: Can the virus live in pasteurized milk? And how do—how will we know which farms are infected? Is there any tracking system that’s happening now? Or is it really as it gets reported out?

BRIGHT: I think either of us can do that—Jen, do you want to do that first, and then I’ll take the next? Or either way? But, yes, why don’t we do that?

NUZZO: So they have found genetic material of the virus in pasteurized milk. They have so far, from the tests done to see if you can grow the virus from milk, have not been able to. I’m reassured by that. I haven’t worried about drinking milk. My kids drink it a lot of times. I am not currently worried about that. I am worried for people who, as Rick said, are exposed to raw milk prior to pasteurization, because of the level of the exposure and because the process of pasteurization has not been able to render that virus incapable of infecting us. So that’s my concern. Regarding tracking, as I said, we’re not doing a lot of testing. So I wouldn’t assume that because you see it in some—know that it’s in some places, it doesn’t mean that it’s not in other places.

BRIGHT: Yeah. And I’ll add to because—and this is where we can learn more from the states, and local levels, and others directly dealing with this. And I will agree that the limited experiments that have been done to show that heat can inactivate H5N1 in milk in a simulated pasteurization process does seem to be effective, if the amount of virus going into that process is low to moderate. And so my concern is the way we consolidate milk from various farms and take it to a pasteurization facility, it involves picking up milk—maybe one truck or a few trucks—picking up milk from various farms. If the ratio of milk from infected farms going into one tanker truck is low—so if you’re picking up milk from ten farms and two of those farms have infected cattle and eight are unaffected you’ve diluted that virus out quite a bit. And I think that pasteurization can handle it. 

But as we continue to see this outbreak spread broaden and spread out across the country and farms, the ratio of infected milk will go up in that tanker, in that—in that batch going through pasteurization. So we don’t yet have data on the effectiveness of pasteurization as that viral titer gets higher going through that process. So that’s why it’s important to pay attention. And if there is anything noted that changes, and the pasteurization is not completely effective, that’s what we need to be completely aware of and be able to respond quickly.

FASKIANOS: Thank you. I’m going to take the next question from Sean Murphy. Has a written question, but let me just see—oh, also a raised hand. If you can say who you are, that would be great. And unmute yourself, please. 

Q: Hi, there. Can you hear me? 


Q: My name is Sean Murphy. I’m the mayor pro tem for a small town in Colorado. 

My question is, what would you advocate on the local level for getting prepared for a pandemic like this? Thank you. 

BRIGHT: I think that was—

NUZZO: So—go ahead.

BRIGHT: On the—on the basic level we know how this virus spreads. So I think it’s going to be—it sounds simple, but I know it’s going to be a very difficult conversation coming through COVID, what we know is hand hygiene can rid the virus—if you come in contact with it, you touch it, washing your hands actually can prevent you from getting infected and transferring that to your eyes, your nose, or your mouth. We also know that respirators—N95 respirators—are quite effective at managing the spread of influenza. So it could already be at the basic level in the community just awareness of hygiene, once again. No one needs to start wearing a mask right now, or being extra overly conscious for H5N1. But now’s a good time to reinforce just general hand hygiene and the concept that if this were to spread, we might have to wear respirators to protect ourselves again.

NUZZO: And I would maybe just add, I think in the short term the thing that I’m most worried about is protecting these farmworkers. I’m quite concerned that there are a number of reasons why infections in this population may not be—might not be found as much as we would like to be able to find them. One, just to understand what’s going on with this virus but, two, really to protect these farmworkers. And so I think really outreach to providers who, particularly in farming communities, that these farmworkers may rely on, just what the symptoms are. You know, these—so far, the two known cases, publicly known cases, have had eye infections. And that might not be what clinicians think to try to test. It’s unfortunately a little cumbersome to test that right now, but nonetheless it would be important to think H5N1 if there were a farmworker with an eye infection. 

So just in the short term, just doing outreach for the purposes of protecting farm workers. In the longer term, agree with the list that Rick gave. I will just also queue that this virus—we don’t yet know what a pandemic strain of H5N1 would look like, and if it will be the same as what we’ve seen so far. Again, the data that we have on H5N1 is quite limited. But the data that we have are enough to be concerning. We do typically know that influenza may be different than the SARS-CoV-2 virus that causes COVID-19. And one key difference could be that influenza viruses often are hard on kids. And there was a lot of debate about schools and whether kids should be in schools. I will tell you, I was on the side of keep the schools open. 

It’s harder to argue in the context of a virus that is disproportionately affecting kids, a virus, influenza, we know is often seeded to the community from kids. And so that, I think, creates another scenario. So if I were a local leader, one of the things I would be doing is if there were a pandemic, what actions would we as a community be willing to take to stop the spread of this? What are the red lines for us as a community? What would make us shift our feelings on those red lines? Think about if we did need to start vaccinating again, how would we do it? Could we build on the infrastructure that we just used for COVID? Does that infrastructure still exist? 

So I would be kind of going through those scenarios, again, hoping we never, ever need to act on them. But that if we did, that we would, you know, be able to hit the ground running, instead of trying to figure it out de novo.

FASKIANOS: Thank you very much.

The next question from Steven O’Connor, who’s an attorney: Is there an mRNA H5N1 vaccine in the pipeline?

BRIGHT: That’s a great question. And a good answer is there are multiple H5N1 mRNA vaccine candidates in development. And Moderna has started a clinical trial. And also, BioNTech and Pfizer are also in clinical studies with H5N1 mRNA-based vaccines. Also, caveat to say that we’ve had—they’ve had many years of work in developing an mRNA-based vaccine for influenza. And there have been some technical challenges to address in that process. So we’re still learning. So even though they have a candidate in the clinic for H5N1, we still may need to optimize that in some ways. But the good news is that they are moving forward. They’re doing this at risk. And we should have some clinical data read out in a matter of months, I would say.


I’m going to go next, an oral question from Patrick Jordan, if you can accept the unmute prompt and tell us who you are. There we go. I see you’re unmuted. Nothing. OK, waiting. I’m going to go next to—there are a couple of questions in the chat about unpasteurized products. So one question about pasteurized eggs are not readily available. And then there’s another question from Deirdre Goins about, does this warrant a state pulling unpasteurized dairy products from shelves? Because this—you know, the outbreak. And how can states begin testing farms? What policies would you recommend, you know, putting into place at the subnational level?

NUZZO: So in terms of unpasteurized products, first of all, there’s long been reasons to avoid unpasteurized products. Eggs, obviously, can be cooked. So that’s—you know, but eating raw eggs has long not been recommended. So I personally, you know, fall in the position that this has long been public health guidance and it should continue to be. I worry about the sort of rise in sort of, you know, fashion, I guess, of raw milk as a product that some people perceive to be beneficial. I quite worry about raw milk, not just the consumption but also, as Rick said, touching it and other exposure. So, yes, unpasteurized products represent a risk. 

I will say, though, in terms of testing, I think one of the things—there is a notable difference in terms of our approach to handling H5N1 chicken farms versus cattle farms. Sorry, if you call them cattle farms. And the difference is that this virus has typically killed the chickens. And so the response to H5N1 in chicken farms has been much more aggressive, in part, because of the risk to the industry. So while I worry a lot that this virus is circulating on cattle farms and we are unaware because, you know, the cows are not being killed and because we know that asymptomatic cows can be infected. We don’t fully understand their abilities to transmit it, but we have to assume that that’s possible, in chicken farms it’s different. 

Another key difference also is that there are financial incentives for identification and reporting of infections in poultry farms that don’t exist yet for cattle farms. And so I worry—my worry is focused right now on the cattle farms, because I think that the incentives are really, really important. We obviously have to balance multiple priorities here. The objective isn’t to put our farmers out of business. The objective is to be able to produce these products safely in a way that won’t harm the general public, but also won’t harm the workers who are involved in their production. And I think the incentives are key to that. 

This is why I’m so interested in making sure we have available tools that can protect workers on these farms, such as personal protective equipment, but ultimately vaccines because it is—well, as Rick said, it’s hard to wear these personal protective equipment in the context of these farms. And, you know, we want to make sure if we have a tool that can protect humans, we should be using it on these high-risk individuals. 


BRIGHT: No, I mean, that’s exactly right. I mean, and the does bring up a question, maybe some things to think about at state-level policies. There could be discussions and considerations to making the vaccines that we have in the stockpile available to vaccinate high-risk individuals, those working on farms—dairy farms, or in the slaughterhouses, or milk processing. And so even though the vaccines that we have in the stockpile may not be exact match of what could circulate if this were to become an efficient human-to-human transmitting virus, we’ve done a number of clinical trials through the years with our stockpile and what we call prime-boost studies or mix and match studies. And there’s a number of published data that show if we were to give the first dose of vaccine now, with what we have in the stockpile, it would prime the immunity of those of the highest risk. 

And we know that takes two doses of an H5N1 vaccine to make a sufficient level of immunity in a person, because this is a virus we’ve never seen before in people. But the data show that we published in our prime-boost studies, that if we do the first dose with what we have now on the stockpile when that virus takes off, and we have the match to vaccine, we can give that second dose and it will actually make that immune response really robust to match what was circulating even before that virus took off, and then the circulating strain that became a pandemic. So there’s a lot of data to support discussions and considerations for perhaps immunizing at least a first priming dose in individuals at a high risk.

FASKIANOS: Great. And just to say that that question from Deirdre Goins, works in the office of Representative Andrew Gray in Alaska. 

So Patrick Jordan, who was unable to unmute or we were having technical difficulties, wrote something I want to just read out loud: Getting back to the mayor pro tem from Colorado, here in Ionia County in Michigan, we’re at ground zero for avian flu. Our health department is working closely with the state. We’ve tested twelve to fifteen dairy farm workers with zero positive. But the critical thing here, with the migrant farmworkers, is building relationships with the organizations that serve migrant families, that migrant families trust and are used to working with. So I just wanted to read that because I think that is a good contribution to the discussion.

BRIGHT: Irina, can I say—

FASKIANOS: Yeah, please go ahead.

BRIGHT: I’d say that we should make a poster with that statement on it, because that is crucial. I mean, and we’re learning that much of the workforce across the U.S. at highest risk are likely to be migrant workers. And there are so many issues with getting health care and tracking or monitoring for infection or sickness, or treatment and recovery in this population. And the relationships that are built now around trust and trying to help and make things available are critically important, because in the context of an outbreak and something really devastating it’s that much harder to build trust and work on those communication lines.

NUZZO: And just to add that that’s likely to be a durable benefit. Meaning that it’s not just an avian flu benefit to doing that. I mean, this was critical for the H1N1 pandemic in 2009, which didn’t involve avian—an avian influenza virus, but nonetheless this was a vulnerable group. And there was some stigma because the virus was thought to, you know, have started in Mexico. So there was—there was really to do that. There was a mumps outbreak on mushroom farms. So, anyway, this is something that I think public health would benefit from, just regardless, because I think the overarching lesson from all of these events is that, you know, outbreaks, epidemics, pandemics, they expose our vulnerabilities. And that remains a highly vulnerable population and worthy of having strong relationships and, as Rick said, a high degree of trust.

BRIGHT: And, Irina, as you get the next question, I’m going to add one more, because that was such a good comment. It was loaded. I loved it. You should have the next panel—he can be on the next panel. But he also mentioned the fact that they’re testing some exposed individuals, monitoring. One of the biggest gaps that we have right now in this outbreak, in the animals as it adapts to humans potentially, we don’t have access to those data. So we have no data in serology, or the virus, and the things that are happening in people or the animals. And we understand that there are jurisdictional challenges. There are database challenges. So many issues, even in the United States, between the federal level and the state level, the state and local, local and the farm, and et cetera. 

And it’s so important at the non-federal level—wherever you fall in the local, state, wherever it might be—sharing data in real-time, as real-time as possible, is the only way we’re going to understand what’s happening and be able to sharpen our tools that we have and be able to get in front of this virus. If the data aren’t shared for whatever reason, made publicly available for whatever reason, then we will be caught flatfooted. We won’t know that this is taking off and spreading and killing a lot of people until so many people are infected and dying that we can’t stop it any longer. The key is held right now in the sampling that Patrick just described.

FASKIANOS: Thank you.

Next question from Jonathan Olvera in Lacy Lakeview, Texas: What season do you believe will be the highest risk for transmission? Or what season should we be aiming for our preparation?

NUZZO: I don’t know that we know this answer. I mean, there’s a couple of ways of looking at it. Typically, respiratory flu viruses, we see a higher activity in the months that we go inside where there’s not a lot of humidity. So that’s the kind of late fall, early winter, early spring. Why we’re seeing these infections now, don’t know. Maybe tied to bird migration. But we’re still learning about this virus. And I would say that’s one of the concerns that I have—and I’m just going to—I’ve been looking at the questions in the box and there’s a lot of questions about where. And I would say we can’t answer where because the type of testing that we’re doing is—we’re only finding cases where we are shining a light. And we are not shining a light in enough places to know for sure. 

We should be shining a light so we can answer these questions. So we don’t fully know why it is now. I worry, though, that we are looking at the numbers and looking at where the cases are and drawing the conclusions on not only incredibly limited data, but possibly highly biased data. So one of the concerns I have is if you look at the USDA map of which farms—which states have infected farms, that map has remained unchanged for weeks, despite the fact that they keep finding more and more farms in the states that have already identified outbreaks. So this virus is moving around. We’re finding it in wastewater. It may be from wild birds. We don’t know. But the number of states reporting outbreaks hasn’t changed. 

So that that makes me highly suspicious that what we’re seeing is an artifact of our surveillance and not an indication of the viral activity. So I worry that some people think that this is on the nadir because we just haven’t found more and more states, and that this is just on the way out. I would love that to be true. But I cannot tell you that, based on the data that I’m seeing. So that’s my overarching, like, take home for everyone today, is don’t assume evidence of absence is evidence—you know, that the absence of evidence is evidence of absence. We really don’t know where this is. We need to be much more proactive in our testing to get ahead of it. 

One way—you know, people have asked me, well, if we’ve only had two human cases in dairy workers, and those cases have been mild, does that mean this virus may be much more mild than we think? If we did serology studies that told us that, like, 90 percent of the population had already had this virus, that would change my opinion about it. But we haven’t done that and we don’t know. I would like to see us do much more testing to better answer these questions. I think the fact that in the 1997 outbreak when they tested healthcare workers, they did serologic studies, they looked for evidence of prior infection, they found that these workers likely were infected and that many of them didn’t have symptoms. That was that virus, not this one. But that’s interesting and important to know. But we haven’t done the kinds of studies that would allow us to better answer some of these questions. And that’s to our peril.

BRIGHT: Yeah. I’ll just add too H1N1 started in April, went through May, June, the summer is when we had the waves. 1918 H1N1 pandemic also burned through the summers. So it started in the spring and burned through the summer.

So it’s unusual that we don’t see—when we see these pandemic flu virus outbreaks really take off in the spring and go through the summer. This is unusual, non-seasonal influenza virus. I worry that we might—if it abates in this summer, that we might think it’s under control or under management. And it will cloak itself within the seasonal winter respiratory viruses because we don’t have test monitoring for H5. We’ll just think is influenza A and we’ll miss it. And it will adapt during that time, and then when the spring hits next year, it’s really six weeks—six months after that when we could see this resurgence. So we could be blessed with a window of time to prepare, but I would not relax if I did see—if I saw the reporting drop in cases lower or the next month. I would intensify preparation for the spring.

FASKIANOS: So there’s a question from Mayor James Fahey of Corrales Village in New Mexico: Do you know if anything is being done on swine surveillance, as it is my understanding that they both have the Alpha 26 23 receptors?

BRIGHT: There is some surveillance in swine. I mean, again, when we think about the ratio of testing for human influenza viruses versus swine surveillance or, you know, cattle surveillance, or other animals, it’s very limited. But, I mean, the infections that we see in pigs historically aren’t that harmful to the pig. So the pigs can be coinfected with a seasonal influenza virus, human strain, and a H5N1 avian strain. It really is in the combination of those two viruses in that mixing vessel that we see things that can emerge. And we see actually an unusual triple reassort, we call it, strain that emerges most years lately around the state fair time. And so we constantly see this unusual reassort – (inaudible) – come out of pigs around state fairs. And it’s affected several states for many years. 

And so I would say, because of that we have some decent surveillance in the swine population. It could be bolstered, probably should be, in context of what we’re seeing now. The thing we don’t have a lot of is reporting and sharing of those data. So even if farmers, and veterinarians, and others are testing in swine, there is not a lot of information about viruses that have been found in swine. They’re not sharing the sequences, necessarily, or posting them in the database, like, GISAID database where most influenza sequences are collected and analyzed. And so if there is additional testing being done in various animal populations, I can’t emphasize enough the importance of submitting and sharing that data into a database that will allow us to monitor for mutations, evolution, or recombination events in any of those animal populations to be better prepared for a human outbreak.

FASKIANOS: Wonderful.

And there was a question asked about is the stream readily detectable by wastewater surveillance. Jennifer just answered it in the answer thing. I’m just going to read it for the—

NUZZO: I’m trying to get to these questions. I see a lot, so I’m just typing them if I can.

FASKIANOS: Yeah, no, that’s great. CDC is doing a wastewater testing for influenza A. H5N1 is not—is one, but not the only. And it will soon do testing for H5 specifically. And she put in the chat the link to the CDC.gov. So you should take a look there. 

We don’t have much time left. We’ve got, like, three minutes. So I wanted to just ask—this is probably a good question—how would an H5N1 outbreak compare to COVID-19, given low uptake of the most recent COVID-19 vaccine? What can be done about vaccine hesitancy in the public? And that comes from Steven O’Connor, who asked a question earlier. So if you could answer that and leave us with any final thoughts, that would be great. And I’m sorry we couldn’t get to all the questions here.

NUZZO: So one key way is that, you know, I would say a blessing of COVID-19 is that it largely spared kids. It didn’t fully spare kids, but compared to influenza viruses it did. We don’t know what an H5N1 pandemic will look like. But the fact that young children, as well as older adults, could be affected—possibly young, healthy adults. You know, we just—there’s a larger age range, I think, to worry about. So that is—that is one key way. I am worried about our willingness to do what it takes to respond to a flu pandemic now, following a COVID-19 pandemic, given sort of where we are politically and where we are just from a pandemic fatigue standpoint. 

I will say that it is important to note that we do regularly use influenza vaccines. But a pandemic H5N1 vaccine would not be like a regular seasonal flu vaccine, likely because, as Rick mentioned, it would use an adjuvant, which is an additive that’s meant to provoke a higher immune response. That’s not something we use that frequently in our vaccines. And I think it’s something that warrants specific conversations with the public about what adjuvants are and why we would use them and what it would mean that they might have more of a reaction than they would otherwise get, and why that potentially is beneficial. So I think there’s a lot of work that we have to do on the front end to talk to people about these vaccines, to hear their concerns about it. Anyway, I’m just—I’ll stop there so Rick can say—get some words.

BRIGHT: Well, I think that’s important. I think the conversation should start now. And they just start in the high-risk communities. I think they should start—the lessons for from COVID-19 vaccination is there’s a lot of distrust. There was a lack of information and details from the federal level to the state and to the locals. And we should now use the time we have to have those conversations, build those trusted messengers and relationships—on the farms, in the communities, in the barbershops. I mean, I’ve worked with a lot of groups that taught us a lot of lessons. Now’s the time to have those conversations. And you can have them with seasonal influenza. And you can talk about the differences in how bad different influenza viruses can be and the importance of vaccination. 
Jennifer has mentioned something that’s really critical in avian influenza viruses or pandemic influenza. It hits the very young and the very old hardest sometimes, and sometimes they’ll hit those with the most robust immune response. Sometimes your body’s immune response does more harm to you than the virus itself. So it’s really important to think about educating everyone for vaccination to make sure that they are protected when that time comes. And I’ll leave you the thought of we are better prepared for influenza than any other pathogen, and therein lies the rub. We can’t be complacent. We can’t think this is going to pass. We must do everything now in this window of opportunity to educate, communicate, and prepare.

FASKIANOS: Wonderful. That was a great note to end on.

So thank you both, Dr. Jennifer Nuzzo and Dr. Rick Bright for sharing your expertise with us today. And thanks to all of you for joining us for your questions and comments. We will send a link to the webinar recording and a transcript. Until then you can follow Jennifer Nuzzo on X at @JenniferNuzzo, and Rick Bright at @RickABright. And, as always, we encourage you to go to ForeignAffairs.com, and ThinkGlobalHealth.org for the latest developments and analysis on international trends and how they’re affecting the United States—and, of course, CFR.org. And please do send us your suggestions for future webinars by emailing [email protected].

So thank you all again for being with us. And thank you to you, Jennifer and Rick, for your time. We really appreciate your expertise.

BRIGHT: Thank you. Been a pleasure.



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