Mosquitoes and Plastic Pollution

August 2nd, 2021

A conversation with Dr. Desiree LaBeaud, Professor at Stanford University, about her career as an infectious disease paediatric doctor, her arbovirus research work in Kenya, and her new nonprofit HERI-Kenya.

Elena: Most of us know that plastic pollution is a big problem. Plastic is made from fossil fuels, it's not biodegradable, and it's everywhere you look and in most of everything we use. The fact that plastic persists in the environment has multiple ecological consequences, but your concerns with plastic come from its effects on human health. Could you tell us about the connection between plastic and the work you do as a research physician?

Dr. LaBeaud: Of course! I study mosquito-borne diseases. We call them arthropod-borne viruses or arboviruses. We've been uncovering the great burden of these infections in different parts of the world, particularly Kenya. We were trying to understand human exposure and disease consequences, but we were also doing entomology, a lot of trapping of mosquitoes. And we started to find that we were getting tons of mosquitoes around trash dumps or yard shops, which are the players in the informal plastic recycling trade where they collect plastic in Kenya.

Dr. LaBeaud finding mosquito larvae with colleague Bryson Ndenga Source: HERI-Kenya

Dr. LaBeaud: We were also doing some intervention programs in the schools, talking to kids about where they found mosquitoes in their neighborhood. The kids were coming back saying they were behind their houses, and so forth. So trash has a lot of health impacts. Everybody knows that big trash breeds rodents, and rodents can spread different infectious diseases. But our interest in trash, particularly plastic pollution, comes from the fact that when it rains the plastic fills up with a little bit of water, and hot water is a breeding ground for different types of mosquitoes, particularly the aedes species mosquitoes, which is what causes dengue, Zika, chikungunya, yellow fever, and so forth.

So all this plastic is breeding mosquitoes, and people are getting sick with these viruses, and that's a big problem. On top of it, because there's no formal recycling, what ends up happening with most of this plastic is that it gets burned. And so when plastic is burned, of course, that leads to air pollution, and air pollution kills about six million people a year. The open burning of millions and millions of tons of trash in the world every year contributes to death and health problems. There's also plastic in the ocean, which leads to even more problems. Everything's connected. We're surrounded by this problem. And so, of course, it has a multifaceted impact on health.

Elena: You're right. But you are taking action! To combat this plastic pollution problem and its relation to health, you founded a nonprofit, the Health and Environmental Research Institute – Kenya (or HERI-Kenya for short), with two of your colleagues, Francis Mutuku and Bryson Ndenga. With HERI, you hope to address this problem in Kenya. Could you expand on why you chose Kenya? You were talking about the problems you found there, but why were you there to begin with?

Dr. LaBeaud: It all comes down to people, right? I started in Kenya because my mentor was working in Kenya. When I started doing this research, about 18 years ago now, I was a pediatric infectious disease fellow. So you go through your training, you go to college, you go to medical school. In medical school. I decided I wanted to be a pediatrician. So I did my pediatrics training, which is three years. And then, when I was in my pediatrics training, I went abroad for the first time, to Laos. It was in the middle of monsoon season, and unfortunately I witnessed a lot of children dying from dengue. That really had an impact on me, and I realized, "wow, if I got some infectious disease training, I might be helpful in the developing world!"

So I went back and I did an infectious disease fellowship. And so that's another three years. And in those three years, you do a couple of years of research. So for my research project, I went around and I interviewed with all the different mentors, and I found a really great mentor. His name is Charlie King. He's still my mentor. And he was working in Kenya. He is a schistosomiasis expert. Schistosomiasis is a different vector-borne disease, it's a parasitic infection. But anyway, he had this side project on something called Rift Valley Fever Virus. I liked that project because it could kind of be my own, and also because when I was in high school, I was very much into the environment, and this project had a lot of environmental context in it.

Mosquitoes are ectotherms. They're out there at ambient temperatures, and their environment is important – superimportant –for disease transmission. Also, it was in Kenya, and I knew I wanted to work in sub-Saharan Africa. So I started working with Charlie in Kenya, and I started developing relationships with all the wonderful, brilliant Kenyan scientists that I get to work with. And those relationships have just grown over the years. And the reason why we're starting a nonprofit in Kenya is because I love Kenya, it's like my second home, and a lot of my friends and family are there.

Landscape in Kwale County (Kenya) Source: HERI-Kenya

Dr. LaBeaud: So I've been working with Francis and Bryson for many, many years on these infections. I don't get to really practice a lot of medicine when I'm there. I go as an observer in the medical field. And I have been doing research. There's a lot you can accomplish in the clinics, and there's a lot you can do in research, but there are some things that you can't really do in either. And it just got to the point where we wanted to implement some changes in the ground that you can't really get funded by research. It doesn't work that way. So we needed a different way to execute change and really dig in. The nonprofit space seemed like the right space for that. So that is what we're trying to do with HERI. We are really focused on inspiring community action through education and awareness of how the environment and health are intricately connected. We believe that education and awareness can empower, and that the spreading of knowledge may promote grassroots activism, which in turn may lead to some policy changes on environmental health issues.

Elena: Was founding a nonprofit something that evolved after encountering these roadblocks in funding, or is it something you had in the back of your head and were looking to do at some point?

Dr. LaBeaud: I always knew I wanted a nonprofit, but I didn't know what it was going to be in. Now it's going to be in creating a circular economy for plastic. So now a person who is a paediatric infectious disease physician is going to be working in plastics! But that's OK. That's why life is fun, right?

Elena: Right. Where there's a will there's a way! So you have founded HERI. Can you elaborate on the work you're planning to do with this nonprofit? Give us some specifics.

Dr. LaBeaud: Well there are several things we're planning to do. Up to now, and for a long time, we've been researchers, and we've generated a lot of knowledge and understanding about this mosquito-borne disease, about how and why it is happening. But we haven't been able to translate those research findings into changes in the community. Some things have happened —health has definitely been getting better because of our research,— but we felt that we had not triggered much change, like translating that science into community action that in turn makes communities healthier, and at the same time makes the planet healthier.

HERI was founded this year. We have five goals we're hoping to accomplish in the next couple of years. The first two goals are to educate at least 500 youth and community stakeholders so as to start to create a culture of plastic recycling in Kenya, because, right now, no formal one exists. There are many changes in mindsets and cultural shifts that need to take place for that to happen, but that is what we're aiming at. We are also working on hosting a local scientific conference to strengthen existing strategic partnerships for research and policy change around environmental health issues, as well as create new ones. We also want to pick up and repurpose at least 10 tons of plastic waste from the streets before it gets burned, so that our community members and our mother earth can breathe easier. And we want to do all of this while strengthening the community by creating jobs and economic incentives in this circular economy for plastic.

Elena: You mentioned the need for mindset and culture shifts. Is there currently a stigma regarding trash in the culture that is contributing to the slow or lack of progress in this problem?

Dr. LaBeaud: Yes, there is stigma, and we really need to destigmatize trash. We've led many focus groups at the community level, —all the different stakeholders, the community leaders, people working in this area— and we've found that a lot of people just ignore the trash that's laying around. They don't really see it. They don't perceive the risk that this could actually be harming them and leading to mosquito breeding, or rodents, or whatever it might be.

In Kenya, plastic recycling is an informal trade. There are these people that we call waste collectors, or waste pickers, that go and rummage through waste and pick up whatever bones, glass, metals, plastic, and then they sell that to the yard shop operators and the yard shop operators have their little kind of trash dump where they sort all these different things. And then they sell that metal, that copper, or that steel, or glass, or plastic to these traders or middlemen that then send and sell them to these large recycling plants in Nairobi. Because all the recycling at this point is happening in Nairobi, although there's a plan to actually have a repurposing recycling plant on the south coast of Kenya, just footsteps from where we work and where HERI is. So there'll be some amazing things happening on the south coast soon, which is really good because the south coast is a great place to do this work.

A trash dump, or yard shop, in Kwale County (Kenya) Source: HERI-Kenya

Dr. LaBeaud: Where's the stigma? People think that the people who are doing the waste collecting are getting that stuff so they can go buy drugs. When we've done this work, we've found some drug addiction issues in some of those people, but a lot of them are just trying to make an honest living. And they are actually doing wonderful things for their community: they're stepping in where you'd expect government or industry to step in to clean up sanitation, and that sort of thing. They're actually doing a good job. They're heroes of the community because they're cleaning up this waste, which is causing so many problems. So we need to switch the existing perception a little bit. We need people to see the waste and then understand that picking up is something we all need to get involved with. We're hoping to bring more and more people to the space as a livelihood, including women, because there aren't that many women in the space at all. Bringing more people into it will change the perception of it. It will help turning it into a really cool thing. People will start realizing that it is a good think for the community, but also that you can actually make money off of this plastic waste. Once it's clear that there's opportunity there, then it feeds on itself and the stigma kind of subsides. But changing perceptions requires work. It's not going to happen overnight.

Elena: It sounds like many stakeholders need to collaborate, so I'm glad to hear you're putting so much effort into it. Now, plastic pollution and its link to infectious diseases isn't unique to Kenya. Does HERI have plans to either associate itself with other organizations or expand into other countries?

Dr. LaBeaud: Yes. We're just starting in Kenya for the reasons I told you before, that is, our long term human connections there. But absolutely, this problem is a worldwide problem. And it's only getting worse as more and more millions of tons of plastic are produced each year, which don't biodegrade.

We actually work in other areas in the world, we work in Grenada. I'm bringing up Grenada right now because I'm thinking about it a lot. Grenada is a tiny little island. There's no formal recycling on it because they don't have enough waste to make that financially viable. And so trash just piles up right by the ocean. The most beautiful trash dump in the world, right there on the coast!

But anyway, if we do good work and we can find some general tenets that can be applicable in other places, I think that will be really helpful. Sometimes things work out best when you are actually deeply local, meaning that the solutions that can come up will be purely and specially Kenyan, and will work for Kenya, and maybe Grenada would come up with different solutions. But the idea of empowering people, bringing the problem to people's attention so they can come up with local solutions, that is maybe the work of HERI.

So, HERI's in Kenya for now. And we'll see what the future holds for us. But there's definitely an opportunity to work with others. And I'm so happy that so many people are getting involved in this problem, like yourself, who care a lot about the environment and who are educating people on it, and trying to inspire others to join the cause.

Trash covering a beach Source: Oceanworks

Elena: Thank you, that's very kind of you to say. You mentioned you're going to have to amp up your work because of the increase in plastic pollution. How about in relation to climate change? How does climate change relate to your field of infectious diseases?

Dr. LaBeaud: In so many ways! We actually work a lot on climate change and its impact in vector-borne diseases. As I mentioned a little bit earlier, the mosquitoes are ectotherms, they're completely dependent on ambient temperature for all of their biologic processes. So you can imagine that they're very, very temperature dependent. And so as the world warms, there are some mosquito species for which the temperature is going to get perfect for their biologic processes to be optimally running.

Elena: There are many different species of mosquitoes, right?

Dr. LaBeaud: Yes, there are many, many species of mosquitoes, and they all have their own temperature. For example, the aedes mosquitoes, the ones that spread dengue and chikungunya – which are the ones that we're working on –, like it hot. They prefer twenty nine degrees Celsius, versus the malaria mosquito, anopheles gambiae, which thrives at around twenty five degrees. So, for instance, in our work and in some of the things we publish, we're just showing that as the climate warms, it's not so much that everywhere in the world all of these infections are going to blow up and everything is going to get worse. It's actually quite nuanced. There's going to be some places in the world where it gets too hot for things to transmit and it'll actually burn out. Some places might still be too cool, and then some places that were cooler are going to warm up and it's going to be perfect for them.

We predicted that in sub-Saharan Africa, it's not that malaria is going to go away, but malaria will shift. It will maybe climb up in altitude, putting a lot of susceptible people at risk who had never seen it before. And then dengue and chikungunya, the viruses that are spread by these hot mosquitoes, are going to blow up in sub-Saharan Africa because it's going to be hot at those temperatures most of the year, making transmission really likely. So that's one of the ways in which a warming planet or climate change will impact these infections.

There's other links as well. There's many, many links. I could go on and on. It's hard to unlink climate change from humans and what we do. The fact that more and more people are moving into urban settings also has an impact. When we move into urban areas, we do things in order to sustain life: we need to feed our families. we need health care, we have many needs. For example, I also work in Brazil, and in Brazil, a lot of forest-facing communities will deforest so that they can pay their medical bills, or whatever. Of course, that has an impact on climate change. Because you're deforesting, you're changing habitats, and that leads to biodiversity loss. But it also puts those humans in contact with forest-dwelling mosquito species that maybe they haven't seen before. And so there have been outbreaks of yellow fever in Brazil recently, and then also malaria. All of this is related to deforestation and manmade land use change. And then finally, I'll just mention, because we're all still suffering with covid, that there are direct links, of course, between COVID-19 and climate change. All of these emerging infections, including the ones I study, emerge because we are changing our planet, and our planet is trying to find a new equilibrium.

Deforested land in Brazil Source: Science

Elena: Can you elaborate on the link between covid and climate change?

Dr. LaBeaud: Sure. For that, I need to start by talking about bats. Bats are sweet little things that drink flower nectar. When the climate warms, the flowers aren't blooming when they're supposed to. They don't bloom in the winter, so the bats get hungry. What do they do? They go into the agricultural areas, where there's still food for them, because they're starving. And that's when their excretions mix with other amplifying species, like pigs, and you get this hopping of viruses across species limits. And when you have starving, unhealthy bats, they secrete and excrete a lot more viruses than healthy bats do, so that also amplifies the fact that you have a system on the brink of destruction.

Everything's hurting. And we're living on this tiny floating marble. And we're all together on it. We're all intimately connected with each other, and with all the living things on Earth. You can always find the links if you look. And so, as we hurt the planet, everything on it is suffering too. And this, not covid, this is the crisis of our lifetime.

Elena: Yes, that's true. We're seeing all of these positive feedback loops you were talking about. And those are just a few examples, but they're everywhere. It all indicates that we're on the brink of a catastrophe.

Dr. LaBeaud: Yeah, we're catastrophizing, but hopefully, because we're all working hard, and because we humans can do hard things when we perceive risk, we can change our ways, and we can make progress. We can stop the bad things we're doing, make up for some of the bad things we've done, and make a better future. I don't think we've lost the war yet, but we all need to get busy. This is a crisis, and as in any crisis, people need to stop what they're doing, and do this.

Elena: Yes! I completely agree. It's what I'm trying to do with One Blue Earth, raise awareness what is being done, and inspire about what can be done. Because I feel that many people just freeze against this huge problem. It feels too large for them to face. That's why I am trying to inform and educate as many people as possible. If we understand that we're in this together, we will be stronger. We can help each other, as we help ourselves, and the Earth, and all the other living things on it. All is not lost, there's hope, but we need to get to work, we can't waste time.

Dr. LaBeaud: Yes, we are agents of change if we choose to be. Absolutely. So no need to despair. Just get your hands dirty and do what's right for you and your planet.

Elena: I also wanted to ask you some personal stuff that may inspire young people like me, who are now thinking about what they want to do with their lives. Your trajectory seems fluid, like you always knew your path. Is that so?

Dr. LaBeaud: Everything looks like it was planned when you look backwards, but when you're going forward, you have no idea what you're doing or what you're going to do next. It's when you look back that you make a story out of it. I always had wanted to work in sub-Saharan Africa and so that just worked out in the infectious disease training part. And I've been there for a long time, and now we have the nonprofit, which is super cool, and so I think I'll be there for a long time. That feels nice. But I wouldn't have known at your age.

Elena: It must be nice, to look back and be happy and proud of your story; to be content. You're also a professor. How did you get into teaching?

Stanford University Source: Stanford University

Dr. LaBeaud: I am a professor of pediatric infectious diseases. It's an academic title. I started off as an instructor, and an assistant professor, and then associate, and then professor, which is the final stage. When you get old like me, it's just how it happens. I teach some at the university, maybe more in the future, but right now I'm doing a lot of guest lecturing and those sorts of things. And, because I'm a physician, I do a lot of teaching when I'm on the wards with fellows and students. For a physician, it's a little bit different than for your standard university professor, although I still carry that title.

Elena: I see, that makes sense. I have one last question. What advice would you give someone who is just beginning life after high school?

Dr. LaBeaud: I would tell them that their ideas are important, and they matter. I would say that they need to follow their passion. If you feel strongly about something, or you're really interested in something, follow up on that curiosity. And ask questions. I'm always so impressed with young people today because you guys seem incredibly authentic, and very bold and brave. I don't think I was as bold or brave. I had ideas, but I wasn't sure they were good enough, I wanted to say stuff, but I didn't think I was smart enough to say it. I just kept quiet, and I feel that I should have made more noise. This is your life. Make a lot of noise. And there are a lot of people like me who are older, who are super supportive of that, you know what I mean? We're a very cool older generation and we can support you, you know?

Elena: Thank you, I think that's right. You say that my generation is bold, but maybe it's because we've just been inspired by your generation, because we feel that you accept, even encourage, our being true to ourselves.

Dr. LaBeaud: Yeah. We're comfortable enough to do it. So I would say, just follow your curiosity. Recognize that you are an agent of change. It's incredible what I've seen people do and they haven't even graduated high school. I am lucky I've gotten to meet some of you because it's very inspirational for us, for older generations.

Elena: That's very kind of you to say. We can inspire each other, and work together to change the world!

Dr. LaBeaud: Yeah, absolutely. We're all in this together for sure.

Elena: Thank you so much for your time, Dr. LaBeaud. It's been a pleasure talking to you, and I have learned a lot. I look forward to seeing the difference that HERI-Kenya will make!

To learn more about HERI-Kenya and support their cause, visit their website and follow their Facebook @HERIKenya