Radha and new crew member Garrett Naughton host a conversation with Austin Tang, a PhD student in geographical & sustainability sciences and MPH student in biostatistics at the University of Iowa. They talk about medical geography, its application in public health, and Austin’s recent study on pediatric lead poisoning in Chicago.

Read more about Austin’s study at this link.

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Radha Velamuri:

Hello everyone, and welcome back to From the Front Room. Last week, we spoke with Dr. Lucie Laurian about urban planning, and this week we’re looking at another field that’s at the intersection of place and public health, medical geography. My name is Radha Velamuri, and today I’m co-hosting this episode with Garrett Naughton. If it’s your first time with us, welcome. We are a student-run podcast that talks about major issues in public health and how they are relevant to anyone, both in and outside of the field of public health. We are here today with Austin Tang, a PhD student in the Department of Geographical and Sustainability Sciences here at the University of Iowa. He also started working towards his Masters of Public Health in biostatistics here in the College of Public Health. We are excited to talk to him about the field of medical geography, his research on lead poisoning in Chicago, and much more during today’s episode. Welcome to the show, Austin.

Austin Tang:

Glad to be here.

Radha Velamuri:

Could you tell us a little bit more about yourself and how you came to choose medical geography as your area of focus?

Austin Tang:

Sure. Like Radha just introduced, I am [inaudible 00:01:10], I go by Austin. I’m a PhD student from the geography department, and I joined the program of MPH in biostatistics last fall. I’ve also got my Master’s in geography here at University of Iowa, so this is my fourth year here now. I’m from Wuhan, China. If you’re listening to this podcast, I assume you know where that is. About how I got into the field of medical geography, I think this is quite an interesting journey for me. A little bit of background, my parents, they both work in health-related industries or sectors. My mom, she works at a regional branch of the CDC of China. In China, the CDC system takes a hierarchical structure and every region and city has its own branch. My dad, he’s a doctor, he’s a physician. Although they all have this kind of health-related background, I have never thought of following their paths, and they also did not express anything like they want me to go that way either.

As I was choosing my undergraduate major, I randomly bumped into geography as my major, where I learned a lot about spatial sciences, spatial analysis, and learned how to use GIS, so Geographic Information Systems. For my senior year project, I was looking for some real world topics or problems to apply what I’ve learned. That was when I talked to my mom about it and she was like, “You know we do have some health-related data and I think you can do some collaborations with us.” I was like, “Sure, why not?” I did my senior project on Hantavirus. From that experience, I realized that there’s so much that geography can do to help public health. As I explored this topic more, I realized there is a discipline called medical geography. I thought, “Yes, that’s for me.” Interesting enough, I took a little detour, but this family tradition finally still found me. Then, I found that Dr. Carol, my advisor, she’s an excellent medical geographer and that’s why I ended up being here.

Garrett Naughton:

I guess spinning off of that though is… Can you tell us a little bit more specifically about what does medical geography really look like and the applications you can really use for it in everyday life or the healthcare fields?

Austin Tang:

Sure. By definition, medical geography is a discipline that applies geographical concepts to health-related problems. It’s a pretty encompassing discipline. There’s also this evolution of health geography and this separation of these two closely related sub-disciplines. What I’m saying here is definitely just a very core summary. I think there are two big general topics under medical geography. The first one is disease ecology, which is a more traditional focus of medical geography. Researchers would look at diseases and the risk factors from a spatial perspective and understand the mechanisms of disease occurrence and circulation, both communicable ones like COVID and non-communicable ones like cancer. This is also my main focus. I apply spatial analyses methods to disease outcomes, and I like to call this type of medical geography as hardcore medical geography, not to say that the other topic is not hardcore at all, and this is entirely just my own labeling, no one else used this as far as I know.

But what I meant here is that, under this topic, people work more closely with diseases and the risk factors, so probably more medical by definition. The other topic is understanding healthcare. Researchers would study the spatial distribution of healthcare provision, accessibility, coverage, et cetera, and they can provide public health policy suggestions to the betterment of the system.

Radha Velamuri:

Let’s talk a little bit more about you. You mentioned that you… Medical geography, spatial epidemiology, they all define similar things. I want to talk more about the research you do and how your time in the geography department and your new budding time in the public health department, how you came up with the idea for your research, your project. You recently published a paper called The More Things Change, the More They Stay the Same: Persistent Spatial Inequity in Pediatric Lead Poisoning in Chicago. I want you to walk us through that a little bit, how you came about the idea, what made you decide to pick this city, what made you decide to look at pediatric lead poisoning, and how you ended up publishing this paper?

Austin Tang:

Sure, absolutely. My research, like I just mentioned, I work more directly with diseases or health issues. I have done projects, the one that you just mentioned, lead poisoning as well as… My master thesis was about H5N1 avian influenza in Indonesia. My PhD program, I’m currently looking at antibiotic resistance and bacteria. That paper you just mentioned, it’s a paper that was published earlier this year that I worked closely with my advisor, Dr. Margaret Carroll, we published it together in the journal called Applied Geography. This is actually… I was doing a course project in Dr. Caroll’s class, and it turned out to be very interesting and so we decided to turn this course project into a full length paper. What are other questions?

Garrett Naughton:

I mean, I’m from the Greater Chicago line area.

Austin Tang:

Oh, really?

Garrett Naughton:

I was just wondering what made you choose Chicago? Was it just location based, or was it because they have more of a significant problem with this lead poisoning? Or, is it just a problem that happens with big metropolitan areas like New York, Los Angeles, places like that?

Austin Tang:

The initial rationale is that… Lead poisoning, we know that before 1970s we had lead-based gasoline, we also had lead-based house paints, and also with faucets and pipes with lead in it, and later on these were all banned. But, the impact of lead-based gasoline was quite obvious because you just took that out and you don’t have this air pollution with lead in it, but there are still a lot of houses, old houses, with lead-based paint in them, and they can produce house dusts with lead in them. Generally, a big risk factor is that if you’re living in an area with a lot of old housing and with not very well maintained facilities, you will have elevated risk to have lead poisoning, so big cities with longer histories would generally have a higher risk.

Garrett Naughton:

Is that kind of where we see some of the disparity because maybe the lower income places aren’t going to have the ability to keep up and maintain, and they’re also going to be in the older probably areas too?

Austin Tang:

Absolutely.

Yes, absolutely. Another thing is that we want to look at spatial differences. Like you mentioned, disparity is also a big contributing factor, and Chicago is kind of well known for its disparity.

Garrett Naughton:

Yes, I’m from there, I know it’s tough.

Austin Tang:

We were thinking maybe that would be a good place to look at, and it’s also close to Iowa.

Garrett Naughton:

Yes, it is close to Iowa.

Applications.

Austin Tang:

Yes.

Radha Velamuri:

Can you tell us a little bit more about how you think systemic racism plays a role in your research, or is specifically for the Chicago study?

Austin Tang:

Yes. Okay, I think I still need to introduce, walk you through the papers method and findings, and then we can talk about how we think some of the back-play stuff.

Radha Velamuri:

Okay. Let’s talk a little bit more about the methods for how you did this research. Can you tell us a little bit more about exactly how you went about doing this geographic research?

Austin Tang:

Sure. We wanted to look at this issue from a temporally dynamic perspective, but also spatially how it varies across space in the city of Chicago. We gathered data for 15 years, from 1999 to 2013, and looked at the percentage of kids screened with elevated blood lead level, how the rate has changed over time within each community area of Chicago. We also considered other risk factors. We gathered census data and did a spatial regression analysis and found some significant correlations or contributing factors for lead poisoning. We also did hotspot analysis to detect where our persistent higher rate of elevate blood lead level are in Chicago.

Radha Velamuri:

What’d you find out?

Austin Tang:

We basically found out that there are persistent hotspots in south side of Chicago, although in 1999, the average rate of elevated blood lead level was around 40 in the city, but when it goes to 2013, it became less than 5%. But, like I just mentioned, there’s still persistent disparity in the city, so the hotspot did not fade away. The south side still has significantly higher rates of elevated blood lead level compared to its surrounding areas and the rest of the city.

Garrett Naughton:

What do you think caused that decrease? Is it just efforts to actually help the lead levels in that area?

Radha Velamuri:

I mean, I’m sure there were policy efforts to eliminate lead in paint and eliminate lead in certain packaging materials and things like that, so I assume that would’ve helped. Active, maybe, lead testing, do you think that could have played a role?

Austin Tang:

I think so, yes, maybe there’s better coverage for testing. Also, with more and more houses getting renovated, people just generally have less exposure to lead.

Radha Velamuri:

But, what your research is telling us is that there’s still this hotspot in the south side of Chicago that, despite a lowering of lead levels throughout the entire area, there still remains a higher level of elevated blood levels of lead in the south side of Chicago relative to the rest of Chicago.

Austin Tang:

Yes.

Radha Velamuri:

Okay. How do you think… I mean, we hear south side of Chicago maybe isn’t the safest place or things like that, you hear all these stereotypes. I mean, you’re from Chicago, and you’ve definitely heard this?

Garrett Naughton:

Right, yes. I understand, and it’s just disparities that occurred to make it that way, and the way that people just ended up there that might have had a better opportunity if the systemic racism wasn’t as prevalent.

Radha Velamuri:

Exactly.

How do you think systemic racism played a role?

Austin Tang:

Absolutely. We actually found a significant correlation between lead poisoning and education attainment, renter occupation of the houses, minority population, and obviously average house age. I think these are all… You can see them all as proxies or partly results from systematic racism. We know that in the south side of Chicago city, we have a higher percentage of minority population. At the same time, we know that they also have a higher average house age because of historical reasons like redlining and other housing discrimination.

Radha Velamuri:

For those of you who might not know what redlining is, it’s this discriminatory practice in which services are withheld from certain groups of people in certain neighborhoods which are classified as hazardous or not really ideal for investment. These neighborhoods are… They have racial minorities, ethnic minorities, low income residents, and they have been essentially closed off from access to good resources, or they live in more dangerous areas purely because of systemic racism and certain efforts on part of individuals in the government to separate and segregate individuals.

Austin Tang:

Absolutely. Those are the areas that got left off in this history of community development. What people do when they try to invest in an area, they just come in and renovate the houses, build newer houses without lead poisoning, without lead-based pipes. When a region is developed, they would come in and renovate older houses just to have new buildings, and these areas they did not get enough resources to keep up with this development trend. They also have just higher average house age, which is a significant risk factor for lead exposure.

Garrett Naughton:

I guess going off of that, because that’s one way that an effort could be made to reduce lead exposure, lead poisoning, what other efforts would you like to see or could be done by either local government or even individuals that could assist in the decreasing of lead exposure?

Austin Tang:

Another very interesting finding we got was that, although gentrification… We see gentrification going on in Chicago very extensively. In those gentrified areas, we see a dropped rate of elevated blood lead level, but if we also look at the demographics of that area, the change over time, we also see that there is a significant drop of minority groups and huge increases in median household income. We can see that these kind of processes of gentrification would drive those minority groups out and also drive those original residents that could not afford this increase in life expenses. Although gentrification brought down the lead level in children, it did not help the original residents that lived there.

Garrett Naughton:

It’s a double-edged sword with gentrification.

Austin Tang:

Yes, right. Definitely. I think if we want to really help those people we intended to help, I think we should provide pathways that is not reliant on just moving to another area. We have to help them on site, maybe provide more resources for better renovation or better checks at houses that are old. We also mentioned that there’s a significant correlation between renter occupation and lead poisoning, so maybe it’s because that renters have less agency in controlling this issue in the house because that’s their temporary…

Radha Velamuri:

Housing?

Austin Tang:

That’s their temporary housing. Maybe we can also require the landlord to better account for this exposure or this risk in the housing that their leasing.

Garrett Naughton:

I guess switching gears… Looking forward a little bit, you had talked to us before we started recording about your other research that you were doing about antibiotic resistance. I mean, if you wanted to talk about that, you can. But, what future research are you going into and looking forward to start working on?

Austin Tang:

Sure. I’m very, very excited about this PhD project for my thesis, which is about antibiotic resistance. We are trying to study the geography of antibiotic resistance, probably mainly in the US. We know that there’s a huge issue of growing antibiotic resistance, and it’s also highly related with its extensive use in livestock. For example, in Iowa, we have corn and we also have pigs.

Radha Velamuri:

Soybeans.

Garrett Naughton:

Pigs.

Austin Tang:

Pigs.

Radha Velamuri:

Okay. Well, we also have soybeans.

Garrett Naughton:

1.5 pig per person, I think. Is that the stat? Something like that.

Austin Tang:

It’s six.

Radha Velamuri:

I just know that the Iowa Pork…

Garrett Naughton:

Is it six pigs per person?

Austin Tang:

Per person, yes.

Radha Velamuri:

I just know that the Iowa Pork Association is right next to the public library I went to.

Garrett Naughton:

Did you know that the Pork Association actually just runs this state?

Austin Tang:

No.

Radha Velamuri:

Yes, the Iowa Pork Association runs the entire state of Iowa.

Garrett Naughton:

They actually have a big sway in public government.

Radha Velamuri:

I’ve run into them so much, even in speech competitions.

Garrett Naughton:

The Pork Association was sponsoring it?

You get a pound of bacon if you win.

Radha Velamuri:

No, we stayed at the same hotel as the Pork Association.

Well, here’s the deal. I’m vegetarian, I don’t know much about pork.

Garrett Naughton:

Oh, that’s fair.

Radha Velamuri:

But, I do know that there’s a lot of pigs in Iowa, but we also have soybeans. All right, keep going.

Austin Tang:

True, yes.

Garrett Naughton:

There’s a lot of everything.

Austin Tang:

I’ll start with…

Radha Velamuri:

Tell us about pigs.

Austin Tang:

Yes, we have pigs. I think the demographic is we have six pigs per person.

Garrett Naughton:

Which is…

Radha Velamuri:

Six pigs per person?

Garrett Naughton:

I think we need more.

Austin Tang:

Cool. Great.

Radha Velamuri:

Where did that come from?

Austin Tang:

Yes, have more bacon.

Radha Velamuri:

Oh my gosh.

Austin Tang:

You know that antibiotics are used in raising pigs, and we have these large… How should I say this?

Radha Velamuri:

It’s a large… I mean, coming from a microbiome area, I know how bad that is, just a general application of antibiotics for not knowing what you’re using for, it’s just the worst thing you could probably do because it’s just going to develop these resistant microbes that are just going to be so tough to deal with.

Austin Tang:

Yes, and most of them are raised in concentrated animal feeding operations, so these huge, huge hot farms, and they consume really huge amount of antibiotics. A lot of antibiotics used in pigs, they’re also medically important for a human so that they’re also used to treat human infections. I think about a decade ago, people already found that if you live close enough to a hog farm, you have three times of the risk of getting Methicillin Resistant Staph Aureus infection, and now because of that, UIHC now actually screens for MRSA, or Methicillin Resistant Staph Aureus, before doing any operations. We know that there is elevated risk, but we also know that it’s highly related to the local landscape. Here, we have hogs and different animals or livestock would use different types of antibiotics. We would assume that different regions would have this different resistant profile in local strains of bacteria. If we can get a better idea about how the profile differ in different regions, then we can use that to better facilitate our drug or antibiotics administration when it comes to clinical practices.

Radha Velamuri:

I’m really excited for you to go more into this, because you just started this.

Austin Tang:

I just started this, I’m still looking for data.

Radha Velamuri:

Exactly, yes. But you’ve already done one project that… Lead poisoning in Chicago, and now you’re completely switching gears to antibiotic resistance. That shows just how varied spatial epidemiology or medical geography is. I guess just from you, we’ve learned two completely different perspectives are possible. But, could you tell us maybe in a sentence or two why you think spatial perspectives are needed for public health? Why…?

Austin Tang:

Absolutely.

Radha Velamuri:

I mean, we’ve already seen evidence based on your previous work and what you’re working on now, but just maybe if you had to give a campaign pitch for it, why…

Garrett Naughton:

You want people to join us.

Austin Tang:

A more generic introduction, right?

Garrett Naughton:

To join the medical department.

Radha Velamuri:

No, we’re trying to get people to join the cause.

Austin Tang:

That’s true.

Radha Velamuri:

Why do you think spatial perspectives are needed for public health?

Austin Tang:

Absolutely, if you don’t mind taking more than one or two sentences…

Garrett Naughton:

Good enough.

Austin Tang:

I always remember this when I was a kid, my teacher told me, “If you want to tell a good story, you have five W’s.” Can you…?

Radha Velamuri:

Who, what, where, when, why. What about how? That’s an H.

Garrett Naughton:

The question… All the questions.

The how, that’s not as important.

Austin Tang:

It’s not as important.

But, we know that there is where in it. Where things are happening is an essential component of a problem of a story. If you want to tell a good story, you have to tell us where that is happening. I think that is generally what people are interested… Where is an important part of the big picture? We want to know where diseases are happening so that we can get to them more efficiently. This is why it’s important. Why space is a useful perspective is also that disease or risk factors, they happen in space, and the pattern of distribution is not random. I’m trying to think about some examples. Like we just mentioned in the project, the lead poisoning does not happen equally across space, there are places with higher elevated blood lead level. If we can understand better about how the risk factors are distributed in space, we can use that to better understand how diseases are happening in space, or do predictions.

Garrett Naughton:

It’s a deeper connection to an epidemiological study pretty much. It’s a specified area of that, I guess.

Austin Tang:

I guess, yes. Since you are from public health, I’m sure that you all know John Snow.

Radha Velamuri:

We love John Snow.

Austin Tang:

We love John Snow.

Garrett Naughton:

He’s our guy.

Austin Tang:

He’s the father of public health, is that…

Garrett Naughton:

Epidemiology.

Austin Tang:

Oh, of Epidemiology. He’s the father of epidemiology. His famous project is also spatial. He drew a map of London, those few blocks, and he also…

Garrett Naughton:

He drank the water in the area and he just asked people, “Hey, where do you get your water from?”

Radha Velamuri:

He basically identified the distribution of cholera around with a map, and he ended up finding out that it was related to a water plant… Not a water plant, a water treatment.

Garrett Naughton:

It was a water pump. It was a well water pump.

Radha Velamuri:

I should know this.

Austin Tang:

He removed the handle.

Radha Velamuri:

A water pump.

Garrett Naughton:

It was a very famous story.

Radha Velamuri:

Very, very famous.

Austin Tang:

That is, I’d say, it’s essentially a hotspot analysis, because all the cases are happening so closely in space that it must have something there that is causing this cluster. I guess public health from its epidemiology, from its beginning, has a spatial component to it, then I think that is also why we need to take care of that.

Radha Velamuri:

With the aid of technology, you guys can do so much more. You don’t have to rely on small hand-drawn maps.

Austin Tang:

Absolutely, yes.

Garrett Naughton:

You don’t have to ask people, “Where do you get your water?”

Radha Velamuri:

There’s so much data. You get to use data and fancy programs, and I’m sure you code all the time in order to analyze your data and get your results much faster and much more effectively.

Austin Tang:

I think that’s exactly the case. I think a lot of people think of geographers as mapmakers or to photographers, but that is really the last step of our research, which is data visualization. There are so many things you can do other than data visualization, for example, data management. You can put layers and layers of data altogether into one database, and then you can do data analysis, do hotspot analysis, do network analysis, and all different types of spatial statistics.

Radha Velamuri:

I guess we can say medical geography is both the past and it’s also the future.

Austin Tang:

Well, I guess you can say that.

Radha Velamuri:

I think that’s a really good place for us to wrap up. We have one more question for you, it’s the question we ask all of our guests, and it could be about anything. I know it’s scary, but it’s just what was one thing you thought you knew but were later wrong about? It could be about your project, it could be about medical geography, it could be whatever you want it to be. What do you think…? What was one thing, maybe when you came into medical geography, what you thought you would be doing, but you realized you’d be doing a lot more of something else.

Austin Tang:

I started living alone this semester. I thought at the beginning it was going to be hard because it’s just a lot to take care of for just one household, but later I freaking love it.

Radha Velamuri:

Hey, it doesn’t have to be academically related. We ask this question to everyone. We just want to know, because we want people to know that it’s okay to be wrong and you learn from everything. We learned a lot about medical geography today, you learned from living alone.

Austin Tang:

Well, you’re welcome.

Radha Velamuri:

There’s so many things we could learn from just our interactions. Thank you so much for coming to the podcast.

Austin Tang:

Thank you for having me.

Radha Velamuri:

If any of our listeners have any questions, I’d encourage them to check out his paper. It’s called, once again for the people in the back, it’s called, The More Things Change, the More They Stay the Same: Persistent Spatial Inequity in Pediatric Lead Poisoning in Chicago. We’ll see what else you bring to the table in the future.

Garrett Naughton:

Very artistic name you came up with there. We didn’t even get to that, but…

Radha Velamuri:

Yes, it’s a good name.

Garrett Naughton:

It’s a very good name for a research paper.

Anya Morozov:

That’s it for our episode this week. Big thanks to Austin Tang for coming on with us today. This episode was hosted by Radha Velamuri and one of our newest members, Garrett Naughton, written and edited by Garrett Naughton and Anya Morozov, and produced by Anya Morozov. You can learn more about the University of Iowa College of Public Health on Facebook. Our podcast is available on Spotify, Apple Podcasts, and SoundCloud. If you enjoyed this podcast and would like to help support the show, please share it with your colleagues, friends, or anyone interested in public health. Have a suggestion for our team? You can reach us at CPH-gradambassador@uiowa.edu. This episode was brought to you by the University of Iowa College of Public Health. Until next week, stay healthy, stay curious, and take care.