Diagnostics Decoded | Emerging and Infectious Diseases
More Programs and Publications Featuring Dr. Rodney Rohde
In this program:
How can patients truly be prepared for the next outbreak? Respected expert Dr. Rodney Rohde takes us on a compelling journey through the landscape of emerging infectious diseases touching on topics of zoonotic viruses, Alaskapox, Mpox, SARS-CoV-2, AI, predictive factors, next-generation vaccines, and more.
Transcript
Interviewer:
Hi, my name is Deandre. I'm a clinical research professional. I work with oncology patients as well as Parkinson's patients. And I'm here with Dr. Rodney Rohde.
Dr. Rodney Rohde:
Hi everyone. I'm Dr. Rodney E. Rohde. I am a Regents' Professor and Chair of the Medical Laboratory Science Program at Texas State University. And my background is a specialist in virology, microbiology, and molecular diagnostics. And I'm excited to be here with you today.
Interviewer:
So today, Dr. Rohde, we are going to be discussing emerging infectious diseases and how this can affect different patients in different patient populations. So just to kind of get started, what are the primary factors contributing to the emergence of new infectious diseases, and are we out of the woods?
Dr. Rodney Rohde:
Yeah, so it's a great question. There are many, many factors that can precipitate the occurrence and transmission of what typically we refer to as emerging infectious diseases, as well as reemerging infectious diseases. And some of those types of factors include our expanding human population. For example, we're living longer, we're moving into different geographic spaces. We're an aging population, so many of us are more immunocompromised than ever before. The urbanization of the population as well as globalization. And then, of course, things like climate change and industrial livestock production and overpopulation and conflicts, even when you think about what's going on around the world with respect to conflicts and the migration of people across borders, so on and on. And then when you tie it into some of the things we've been dealing with in the last few years, you can even think about the interaction or the integration of how people interact with wildlife perhaps or the foods they eat or the water they drink.
All of those can be really contributing factors to how new infectious diseases suddenly pop up. I always kind of joke with people that even COVID, for example, COVID-19, which is caused by SARS-CoV-2, some of those viruses were probably here. They were probably out there in the wildlife population, whether it was in bats or other types of rodents. And once a human being comes into contact and that virus makes a jump, then we think, oh my goodness, where did this come from? But in many instances, it's probably been around, we just haven't had that interaction or that jump yet.
Interviewer:
Yes, I think the first time I heard of COVID, and they called it SARS, I thought about SARS that started in China. So I thought there was possibly some kind of connection there.
Dr. Rodney Rohde:
Yeah, right. I mean, we've had really three different versions of SARS. We had the first SARS back in 2000, early 2000s, and we had MERS, you might remember, which was Middle Eastern Respiratory Syndrome, which kind of came out of camels. Camel interaction with humans. And then, of course, in 2019, the explosion, once we found out about SARS-CoV-2, which causes COVID-19. So all of those we have dealt with and we're still dealing with, right? So we're not completely out of the woods when you talk about COVID. And even though we are in a time of lower prevalence and lower death rates and things like that, it is still killing people and it is still causing hospitalizations, and we're still learning. There's so much to learn about long COVID and so many other things that are happening that will unfold as the years go forward, I'm sure.
Interviewer:
Right. So, Dr. Rohde, just to give us some background for those who aren't very familiar with immunology and how viruses kind of adapt and how they mutate and whatnot, how do viruses evolve and adapt to new hosts or environments leading to outbreaks?
Dr. Rodney Rohde:
Yeah, another great question. And so, first of all, I'll just mention as a virologist and a microbiologist, I always believe viruses are some of the most diabolical yet interesting agents we face in our world. The viral infection is a very highly and dynamic process. And, in fact, it kind of leads to this constant ongoing evolutionary changes really on both sides of the virus and the host...
Interviewer:
…in the host.
Dr. Rodney Rohde:
Where they interface. And so when you think about that, obviously we know what the virus is. For example, SARS-CoV-2 or perhaps Alaskapox virus, which has kind of recently been in the news. But the host, when you think of a host in most cases we think humans, right? So we're the host, but it can be, as I mentioned, it could be other animals, other reptiles, other amphibians. And what happens is viruses mutate so rapidly, it's really high, probably the highest mutation rate of any biological organism, and that's kind of coupled with really short generation time.
So they really mutate very fastly, and it's in a large population. And all of those factors really allow viruses to rapidly adapt to their host. So again, unlike maybe bacteria or fungi or even other agents, viruses are just so fast with respect to how quickly they can infect and reproduce that they change almost so fast that we have a hard time keeping up. And as you follow the current pandemic and some of the other issues around Mpox, for example, and other ongoing outbreaks, people are often asking, "Why can't we have a vaccine? Why can't we have an antiviral or some therapeutic?" And unfortunately, the answer is going to be, probably going into the future it takes time to do those types of things, whether it's therapy, diagnostic testing or whatever. And the virus doesn't really care. They're so fast and so rapid that we're always struggling to keep up, but we are making strides there with mRNA technology and other types of diagnostics in the molecular area.
Interviewer:
So, Dr. Rohde, how can we better understand the world of wildlife and zoonotic viruses and the transmission of infectious diseases to humans?
Dr. Rodney Rohde:
Yeah, this is really an important question because what happens is it comes down to a lot of things, and one of the primary things we have to understand is that we have to better understand how that wildlife and the virus, and I'm going to throw in something else here called the vector. And so it could be a mosquito vector, it could be a tick vector, it could be something else. But that cycle, that life cycle of how a virus rotates through different rodents, through which wildlife populations, it rotates through what time of the year, seasonality is important, are there other pathological or human conditions that might allow that virus to jump quicker into a human or a rodent or another animal. And so we must spend more money. So funding is part of that. We need more wildlife biologists, we need more microbiologists, we need more public health experts doing research in ecology and population dynamics so that we really start to understand that interface, because you can't take an approach of just a single focus. We tend to call this across the world now one health approaches. And so that means we have to understand animal health, we have to understand human health...
Interviewer:
…everything is connected.
Dr. Rodney Rohde:
We have to understand environmental health. And then we have to understand that all of those add up to one health kind of approaches.
Interviewer:
So from a preventative standpoint, how can we find a balance in wildlife exposure at whereas in one sense, it's deliberate, it's inevitable, and it actually can benefit us by increasing microbiome diversity? So being exposed to nature and all these things can be good for us, but in the same sense can lead to incidental exposure to dangerous pathogens. Is there a balance?
Dr. Rodney Rohde:
Yeah, I think there is a balance. That's an interesting question. I would think that...one way to think about that is in our natural living conditions, in our everyday exposures to other individuals, whether it's humans, animals, plants, crops, dirt, and air, all of those things are going to present us with immune challenges. And so that is part of presenting our body with an opportunity perhaps build defenses and immunity over time. But I would still stress that one needs to be careful and understand kind of what environments they're going into. For example, if you're traveling into an area that has very high Filovirus activity like from Ebola or Marburg, I wouldn't actually recommend you challenging your immune system, because there are no good therapies. We are seeing some vaccine development in those areas. So I think it's about education as well. I actually talk about this sometimes with family and friends who are traveling, right?
So I think one of the things that we don't do real well in health is talk about how critical it is to prepare for travel. And so when you travel right now, for example, right now, certain places in Europe and around the world, they are exploding in dengue virus infections, which is a mosquito-borne virus. And if you leave, for example, Texas, where I live, and you go somewhere like Brazil or Argentina right now, you really should be prepared and thinking about that because your body's kind of naïve, it's never probably been exposed to dengue virus. And dengue virus can be deadly, and it certainly can be really difficult to handle. It's called breakbone disease. It can be very painful and problematic. So I really am a big advocate of public health education, and that really intersects with healthcare. So physicians and other primary care physicians that know their patients, know their traveling. It's really a two-way street, right? I mean, they don't know we're traveling, so we really need to think about it. So I'm often telling people, "You have to speak up, or if you're planning a big trip, do a little research and visit with your physician. Tell them where you're going. Should you get vaccines? Should you be thinking about malaria or some other mosquito-borne disease? Should you be told do not pet?"
To your point about wildlife, some places in this world still have rabies. I'm a rabies expert. It's different if I pet a domestic dog in Texas versus petting a dog in Latin America where thousands of people still die, or Vietnam, thousands of people still die and or have rabies exposures in those types of countries. So again, I think it's just about being educated and having that conversation with your physician and other healthcare team.
Interviewer:
What are some of the most promising approaches to early detection surveillance of emerging infectious diseases?
Dr. Rodney Rohde:
Yeah, as a molecular epidemiologist and former public health professional, I spent a decade at the Department of Health in Texas, in Austin, in the first 10 years of my career, right out of my master's degree and had an amazing 10-year span where I worked with CDC and got to do on the ground efforts with rabies, with hantavirus, with plague. But I also was in the laboratory. So it was a really creative position that allowed me almost a 50 percent in each area, just I can't say enough about how wonderful it was to work in that area, but what I would mention about this is how critical, again, and a lot of this was developed back in the '90s, and it's been going rapidly ever since. And that's really the introduction of molecular diagnostics. That's one key point. So whether you're talking genomics or proteomics, the use of next generation sequencing, the use of what we're doing right now with wastewater surveillance, what an amazing tool to see at least a kind of watching the background noise of what's a normal viral RNA load say in the water of a city's hotels or an airport, for example, versus what might be considered a spike.
What's going on with COVID, with SARS-CoV RNA in a particular city? Can we get some early detection? Or can we get some early surveillance of what might be happening in those cities before it starts a major epidemic? So I think those are really critical going forward is molecular tools, and then the other is kind of old school bootstrap epidemiology. We need to consider how important it is for funding and awareness at the middle school, high school, and early college level, for epidemiology majors, for medical and science majors, for public health majors. Because what we're seeing in the past five years is COVID has really burnt out some of those professionals as well as some people just leaving the field for retiring reasons or pay and things like that. And I can't tell you how important it is to not let that happen because human beings with that expertise are as important as the tools that we utilize in the departments, in the laboratories and so forth.
And then innovation. So going forward, whether it's looking at wastewater surveillance, whether it's doing air quality, actually testing the air through cleaner Airvac systems and kind of trying to get as soon as possible as real time, if not sooner, of what's in the air, what's in the water, what's coming through the food, and also ongoing surveillance of animals, vectors like mosquitoes and ticks. We do this...we did this at the Department of Health in Austin where you trap mosquitoes, you trap ticks, these are all kinds of in the wildlife/laboratory area. It's really fascinating work. I love doing this. And so you start getting a feel for prevalence and incidents. For example, in the mosquito population in Houston, Texas, is West Nile virus circulating in mosquitoes or is Zika circulating in mosquitoes? And once you know that, that's part of the animal health part. Once you know something's going on, then you can start thinking about, well, what do we do if it bleeds or jumps into the human population?
Or what happens if this is an environmental issue? It's in the air or the water. And so again, funding people and ongoing development of those technologies and professional expertise is going to be critical and really can't be let down. We have to sustain that at the national and federal and state level because, as you guys know, you can't train up a microbiologist or a virologist overnight or an epidemiologist or even a physician or a nurse. It takes time. And when you lose that expertise, you don't just plug in a new person, it can be a problem. So we really need to keep that pipeline steady and full at all times.
Interviewer:
What strategies are utilized to create these kinds of predictive factors in different environments? Like you just mentioned the testing of water. Do they do it in specific communities or is it tested in lower income communities? High income communities? What is the strategy for making sure everything is assessed equally?
Dr. Rodney Rohde:
I have some slides on this that actually show the United States and where this wastewater surveillance is being conducted. So yes, typically we try to take these tools, and we try to utilize them in a way that we can do our best at getting our look at high urban areas as well as rural areas. And so there are approaches to that where every state has coverage, and certainly in higher population areas, there may be more reasons to do a suite or a survey of those areas, of those water systems. Whereas if it's in the middle of nowhere with very little human population, we may not do as much. But that's where perhaps we need to be looking for wildlife surveillance or other types of things where it may be important to be monitoring, for example, bats or birds or canines like fox and coyote for rabies or mice for hantavirus or plague, or things like that. So really it's an approach where you try to do it that spends your dollars wisely and that you place the most power for what you're worried about, whether it's environmental, animal, or human. You're using those tools in a smart way as best as you can, and then you hope you can adapt quickly. So if you need to pick up and move to a different area, you can do so in a quick way.
Interviewer:
So there's a lot of talk about AI and everything. So how do you think AI can be utilized in this case for predicting mutations of emerging viral pathogens?
Dr. Rodney Rohde:
Well, I certainly will start with I am not an AI expert, that's for sure, but I do see value whenever you have a tool that can decipher, monitor, and look through maybe just bazillions of gigabytes of data that might be coming in from different detection devices or different surveillance tools. I'm not sure how that will work, but I think the value is in the power of having 24-7-365 monitoring where human beings might have a hard time doing that. Think of all the sources of information and data. I mean, you could be looking at wastewater, you could be looking at migration patterns, you could be looking at hospital intake. Are there surges going on in ERs around the world? You could be looking at air quality on and on and on, animal disease, what are the rates of certain things going on in certain countries? And so I think that's the value, at least in my limited understanding of how AI works. So I'm going to approach it from the standpoint of the power and the ability to never be turned off and just having that kind of power there and that ability to police and do surveillance kind of ongoing all the time.
Interviewer:
How do pre-existing comorbidities such as diabetes, respiratory conditions, cardiac conditions, impact the susceptibility, severity, and outcome for individuals infected with emerging pathogens?
Dr. Rodney Rohde:
Yeah, this is an unfortunate and true thing that we deal with, right? So again, during the COVID pandemic and even the, I'll bring in Alaskapox virus here, that we had the recent death in Alaska in the Fairbanks area, and it hasn't been a big problem. Alaskapox, we believe, is still rare. They've only seen it in seven human beings with one death, but that one death was likely attributed to comorbidities. The person had some really underlying problems. So whenever the human body has underlying comorbidities, it really impacts their ability to fight off disease. So diabetes, like you mentioned, respiratory conditions, COPD, cancer, you're recovering from cancer or you're dealing with cancer, or perhaps you've got individuals with lupus or other types of autoimmune diseases.
Really all of those and many more will impact the immune system all the way down to the ability, for example, if you have HIV, your T helper cell count may be so low that it really can't mount an immune response against another infection. So most people know this, but if you're suffering from HIV, for example, HIV attacks your T helper cells, which is kind of the keystone to your immune system. If you don't have good T helper cell counts, then it has a problem activating so many other components of your immune system. And so what happens when that occurs? The HIV indirectly is working to kill you because what happens is without those T helper cells, people start dying from weird fungal infections.
In fact, that's how we kind of correlated HIV early on in the '80s as people were dying from weird Kaposi sarcoma and pneumocystis pneumonia and other things. It just really wasn't a problem in a healthy human being. And so sometimes even the detection of new agents can come about from people who have comorbidities, because their bodies are allowing these kinds of bizarre infections to occur. So it's really about how it allows that human being to become more susceptible. And then, of course, they typically have more severe disease. Again, if you just look at the most recent issue with SARS-CoV-2 and COVID-19, even from the very beginning, we kind of understood that something's going on here. And if you look at some of the slides I have, looking at age, ethnicity, male versus female, a lot of those will show you the impacts of those types of demographics as well as some of the comorbidities.
So, for example, even looking at age, for example, really 65 and older, you could drop that to 50, but the big impact was 65 and 75 and older, just massive death, massive mortality in those populations. It's easy to forget this, but remember early on in that COVID-19 pandemic, we were really just doing everything we could. We were really wringing our hands when you think about long-term care in nursing homes. How do we deal with this? Because we had no vaccination yet. We had no good preventative measures or treatments. And then here's another really bad outcome that happened because of COVID.
There was so much respiratory infection. Remember, they were turning patients on their stomachs. They were ventilating them. They were doing almost anything they could to keep them alive. The other thing that was happening, unfortunately, during that time, because of that massive respiratory infection, there was a danger of bacterial pneumonia developing. And so many physicians had no other choice but to start prescribing empirical antibiotics, broad spectrum. And everyone knows that that's not the greatest way to start curbing antimicrobial resistance. So data is coming out right now. Some of these studies are being published almost monthly now of the impact of that. And so we kind of slid backwards on AMR, antimicrobial resistance, as well as some of the other issues around antifungal resistance. We're seeing kind of an explosion with Candida auris and even ringworm resistance, which is a fungus. So all of these things, unfortunately, at the time they were doing it, and it's kind of understandable, but there are impacts. And sometimes there's negative impacts. And so we've kind of...
Interviewer:
And then they are making it worse, a little bit. So what are the implications of viral evolution and genetic diversity on vaccine efficacy and the development of next-generation vaccines against emerging infectious diseases?
Dr. Rodney Rohde:
Yeah, I think professionally and personally, and I know a lot of colleagues would agree with me, I think one of the more exciting things that came out of COVID-19 was mRNA technology and how we really pushed through those vaccines. Because those mRNA vaccines are different than our older school vaccines. And it's become really important because your question gets to the point quickly about viral evolution and genetic diversity. So viruses, again, are diabolical. They do not care what you look like, how much money you make, where you come from. They are going to keep on keeping on, right? Viruses are going to virus. And so in the past, we did the best we could, for example, with flu vaccines, we monitored the seasons, we typed, sequenced and typed those different variants of different H1N1 or H5N1 or whatever strain or variant was circulating at the very tail end of the season, the flu season. And then that's what our next season's components would be in that vaccine. So it was basically a really good, best educated prediction using prior data. Well, with mRNA technology we can almost adapt in real time to virus evolution. Not perfect. I'm not saying they're perfect, but they are the fastest tool we have had in our toolbox in my lifetime.
And it may continue to improve, I hope it does going forward, to where one day that we can adapt and create mRNA vaccines to an immediate threat so that we can get on top of that much quicker. I still think what happened with the vaccine issues that we had with COVID was more about getting through the red tape, and then it became an issue of vaccine...oh, what's the good word I want to use, vaccine access, right? So if you live in certain countries, you got it because the U,S, or different places produce their own vaccines. But if you were in other countries, perhaps Latin America or parts of Asia or Africa or wherever, you were relying on other countries to get them to you, certainly that creates some vaccine inequities. And so I think that's a little off your question there, but I think part of the problem was not just in the development of vaccines and the efficacy, but getting them to people. And so I think that's a real lesson we need to learn with respect to equity of vaccines, getting them around. And we are making improvements, because I know countries now are setting up their own shops for vaccine production so that they have it in-house and they're not relying on other countries as much.
Interviewer:
So, Dr. Rohde, can we speak to what lessons can be learned from past pandemics, such as the COVID pandemic, and how can we better inform and better be prepared for future outbreaks? And can you speak to improving current testing methods that have significant margins of error, such as false positives and things like of that sort?
Dr. Rodney Rohde:
Yeah, oh boy, let me get on my soapbox for this one. So many lessons, so many lessons, and I hope we've not only learned them, but I hope we remember them going forward. So let me give you just a few here that I think are really critical. I think one of the first lessons that slapped us in the face right off the bat was a national testing strategy. And whether you talk about that from the United States or elsewhere, I think it's important. Again, remember early on we were relying on the Centers for Disease Control. I've worked there. I have colleagues there. It's an amazing institution, but make no mistake about it. The Centers for Disease Control was built to identify and understand through surveillance and really problematic cases that were sent to them from hospitals and other places around the world. The Centers for Disease Control is not a corporate reference lab that can crank out hundreds and millions of tests in a week. That's just not their mission. And so I think people expected that to happen. And I think CDC and others were a little hesitant to release some of that power. You remember we finally started releasing some of the testing to Quest, Labcorp, public health departments, even at the level of hospitals once the technology was in place and things got better.
And that's what I think we need to learn that lesson is we need to look at our strategies and set that up so that in the future we don't make that same mistake. I think an important reminder in a weird way was the Mpox national emergency. Remember Mpox was just a couple of years after COVID right as we were starting to kind of slide into are we done with it kind of mentality and we really weren't. And so Mpox was a nice reminder that oh my goodness here comes another agent from around the world, it's showing up again. We're tired. We're COVID-fatigued. And again, viruses do not care whether it's Alaskapox, Mpox, COVID-19 coming from SARS-CoV-2 or flu or anything else. So testing strategy I think is really important. The other lesson I think we learned, and I think it was a good one, is that we can move vaccine development and delivery quicker than ever before. Again with the technology I mentioned before. Now we need to explore how we get that more equitable across the world so that other countries can ramp up as quickly as possible. Testing, wow, point of care test. There has to be a focus on that and availability of that testing. You know we had a really an explosion of at home testing and how that kind of rolled out.
And I would just say as a medical lab professional and public health professional that that was really important and I value it, but I still think we need to examine that and what happened and make sure that when we roll out point of care testing that the public understands just because it's negative or even just because it's positive may not be perfect, because a at-home test can be problematic, for example, if it's expired. Or let's say you live in Texas and you leave that box that point of...not point of care, you leave that at home test on your dashboard of your car in Texas where it's 120,000 degrees in my car in July. You might actually not have a test that's working properly, and so we still need to understand that if there's any suspicion with at-home testing that you want to have a confirmatory test run through an established laboratory proper professionals with the proper credentials like a medical lab scientist or other laboratory professional. And that's really critical, because our data is only as good as it is accurate. And so that's important for the public to understand as well, because that needs to be there.
Point of care, another exploding area across our world with respect to can we get tests quick to turn around at the bedside, or in your home, in the nursing home, and the dialysis clinic wherever you're at. And that will help us do better jobs if you don't know where the virus is or the agent is through testing. How do you really develop a good solid public health plan. Right. How do you prepare? How do you set up vaccination post? How do you think about handling wildlife or vectors if you have to deal with that? There's so much that has to go into planning and thinking about it. And my kind of other commentary around this, I've already mentioned it a little bit, I think one of the huge lessons that we have to continue to bring to your audiences like we're doing through this opportunity here is how absolutely critical it is that we continue to recruit and retain the professionals that do this testing whether it's in the hospital labs whether it's in research labs and whether it's in public health laboratories, because these are absolutely life-saving college majors and professional career pathways for people to enter into. We have huge national shortages in public health and medical lab science career areas including hospitals.
And that number has not changed a lot. It was there before the pandemic, and it only exacerbated the problem during the pandemic. So that type of recruitment and retention along with great opportunities for increasing pay and understanding and awareness and recognition is going to be really critical to prepare for future outbreaks.
Interviewer:
So I think that's about it for the questions. But I just wanted to thank you, Dr. Rohde for joining me today to discuss these very important topics, especially that last topic on building trust. I thank you for coming to this Diagnostic Decoded on emerging infectious diseases. This is a very important conversation to have with people.
Dr. Rodney Rohde:
Thank you so much. I really want to take the time to thank Diverse Health Hub. I think this is such a critical movement, science communication, speaking with medical laboratory scientists and public health professionals and others that can really passionately talk about how testing works or how surveillance works or how certain therapies might work. And hopefully this can help us get started on meeting people where they're at and building some of that trust that you talked about, so I look forward to doing this again and again with you, so thank you for having me.
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