Title: Ebola, Measles, and Avian Influenza--The Importance of Emerging Disease Surveillance Description: In recent decades, several emerging infectious diseases have necessitated the need for global responses. We looked at what's being done here in the U.S. to detect and prevent the spread of emerging infectious diseases through surveillance. We'll learn more from GAO's Mary Denigan-Macauley. Related work: GAO-26-107610, PUBLIC HEALTH PREPAREDNESS: Experts Identified Actions to Improve Surveillance for Emerging Disease Threats Released: July 2026 {Music} [Mary Denigan-Macauley:] Surveillance is absolutely critical, and it really requires all hands on deck because we don't know where the diseases are coming from. [Holly Hobbs:] Welcome to GAO's watchdog report, your source for fact based, nonpartisan news and information from the U.S. Government Accountability Office. I'm your host, Holly Hobbs. In recent decades, several emerging infectious diseases have necessitated the need for global responses. This includes COVID-19, which caused tens of millions of deaths around the world and hundreds of billions of dollars in economic costs in the U.S. alone. More recently, we're hearing about a worrisome Ebola outbreak for which there is no cure. Given these emerging threats, we looked at what's being done here in the U.S. to detect and prevent the spread of emerging infectious diseases through surveillance. Here to tell us more is GAO's Mary Denigan-Macauley. Mary, thanks for joining us. [Mary Denigan-Macauley:] Thank you for having me. [Holly Hobbs:] It seems like we're hearing more about infectious diseases. Are they getting worse or more common? [Mary Denigan-Macauley:] Simply put, the answer is yes. Diseases don't know borders. So in this global world, they can literally come from anywhere. And some are reappearing such as measles and others can be new like we saw with COVID-19. [Holly Hobbs:] Where are these diseases coming from? [Mary Denigan-Macauley:] Some diseases are spread human to human. So for example, with measles, that's through a cough or a sneeze. It's highly infectious. Other diseases can come from animals. And, in fact, 75% of emerging infectious diseases are shared between human and animals. And so, a good example of that is what you hear in the news today. Ebola, for example, that's spreading over in Africa. That originated in wildlife and is now spreading human to human. Another example is the avian influenza in birds. It kills birds and it has now jumped to other animals and over to some humans, and the center for Disease Control and Prevention is monitoring that. [Holly Hobbs:] So these are global diseases. But what's being done in the United States to prevent them? [Mary Denigan-Macauley:] So first and foremost, in the United States, is our own good hygiene. Hygiene is absolutely key to keeping any disease at bay. The next thing that can help too is vaccines. So, vaccinations are very helpful for some diseases. What this report looked at was surveillance. And that is all of those data points that are out there that come from hospitals, come from doctor offices, come from going to get tested when you don't feel good and they test to find out what it is. Coming from state departments, local health departments, the international community. All of those thousands of data points come in. And the federal government is looking at it to survey for what diseases might be coming our way or are already here, and then tracking to see when they leave. [Holly Hobbs:] You said that 75% of these diseases come from animals? [Mary Denigan-Macauley:] Or are shared. [Holly Hobbs:] Or are shared. [Mary Denigan-Macauley:] Are shared. [Holly Hobbs:] Shared by animals. Is the industry involved at all in tracking this, is there challenges with that? [Mary Denigan-Macauley:] So on the animal side, industries, such as where your milk is produced or where the, the beef or your pork comes from. We call that industry. And they are absolutely tracking. They don't want their own animals to get sick. So, they're aggressively tracking the spread. They take their own measures to prevent the spread of the diseases among the animals. They are also coordinating with the public health side of things to track. But everyone has their own surveillance systems, and that's what makes it so challenging. If a disease pops up in a hog barn--like for example, we saw swine flu pop up in 2009--if we were to say that it came from a hog farmer, then it would restrict the trade of pork products and cause severe economic concern to the hog producers. So, there is reluctance on the part of industry to want to participate in a surveillance program without protections. [Holly Hobbs:] So for this report, we talked to experts. What did they tell us? [Mary Denigan-Macauley:] We did. So we, with the help of the National Academies of Science, we pulled together a group of 18 experts with expertise in a variety of different areas--because, as I mentioned, some of the diseases can come from animals. So, we not only pulled together public health experts, but also experts from the wildlife, and from the farm food, domestic animal, as well as technical experts. And they said emphatically that the U.S. has one of the best surveillance systems in the world, both domestic and with the work that they do overseas. But they also recognize that given the importance of disease surveillance, we really need to know what's coming our way. How do we track it once it's here? How do we know if it's gone? Or how do we know if it's here to stay? And so, in order to be able to do that and to understand all of those data points that have to come together to make that happen, they identified numerous areas where we need improvement to really have a good system, so that we're not surprised if something hits our borders. The earlier we can stop something, the better off public health is. And so, they talked about the need to, enhance collaboration, better data points that are coming in, ensuring that it's more robust, for example. [Holly Hobbs:] So CDC leads this effort. Do we think CDC should be doing more? [Mary Denigan-Macauley:] So CDC is the main player for public health surveillance. But CDC is not the only player. CDC has to work with thousands of other entities at the state- and local- health department level. They work with the international community. They also have to work with the U.S. Department of Agriculture, Interior, because you're looking at animals as well. And so they did have suggestions not only for CDC, but for all of the different players that are involved, including private sector, including the laboratory. And one of the suggestions that they had was to enhance collaboration, to more formalize them, and to give them the authority to be able to move quicker. And so they were talking about getting a multi-sector working group together. And where you place that depends on the authority. So for example, you could place it in the White House. That would give it more authority to be able to move quicker. And so they had mentioned that. They had mentioned the concern for the public not willing to get tested during a disease outbreak. We had some, concerns with communication during COVID-19 that we've reported on. And so, they said we need to enhance our communication to get the public to understand and to have trust again in the surveillance systems, because it's an important aspect to know who's getting tested and for what. They also mentioned stronger data needs. We have reported over the years about the need for better data to ensure that the data quality is good, that the data is standardized. Because, if you think about this, data is coming from so many different points. And so to be able to pull that all together and to be able to look at it and to look for signals of what's coming is really important. [Holly Hobbs:] So in the U.S. it's coming from different points. It's coming from my doctor's office? [Mary Denigan-Macauley:] Yup [Holly Hobbs:] Public health authorities? [Mary Denigan-Macauley:] Yep. [Holly Hobbs:] State health authorities? [Mary Denigan-Macauley:] Hospitals, Tribes. And now we're talking about the animal sector. It could be coming from a hog farm. It could be coming from the poultry. [Holly Hobbs:] And I assume they're all collecting it in different ways and then... [Mary Denigan-Macauley:] Right. [Holly Hobbs:] So that makes it more difficult? [Mary Denigan-Macauley:] It does, it does. [Holly Hobbs:] CDC has recently gone through some changes. Do we know if it's gonna affect any of these efforts? [Mary Denigan-Macauley:] So during the expert roundtable that we held, that was one thing that was mentioned. It was right in the middle of everything that was going on with the workforce changes and the restructuring that we're seeing that's happening in public health at the federal level. And so, we don't yet know what those changes are going to be, and we don't yet know from the experts what the impact of that will be. Some of the changes are undergoing litigation. So really what we looked at is up until those changes. We have ongoing work that is looking at those changes. And so hopefully we'll get a better understanding of what impact it may have. [Holly Hobbs:] Last question--what's the bottom line of your report? [Mary Denigan-Macauley:] So the bottom line is that surveillance is absolutely critical. And it really requires all hands on deck from the federal government, state, local, Tribal, and our international partners because we don't know where the diseases are coming from. They could be started here or they could come from overseas. It also requires strong collaboration with the animal side because of the shared diseases between the animal and the human. Our experts offered a lot of different solutions to be able to improve upon a system that is already good. But in order to be best prepared for the next event, this offers opportunities to improve. {Music} [Holly Hobbs:] Mary, thanks for your time. [Mary Denigan-Macauley:] Thank you. [Holly Hobbs:] And thank you for listening to the Watchdog Report. To hear more podcasts, subscribe to us on Apple Podcasts, Spotify or wherever you listen. And make sure to leave a rating and review to let others know about the work we're doing. 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