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Twenty years ago, Hurricane Katrina made landfall in Louisiana, and the levees designed to protect New Orleans failed. Huge swaths of the city flooded, and 1,600 people were trapped inside Charity Hospital. Physician Erica Fisher was working in Charity’s emergency room at the time, and she and her colleagues fought for days to keep their patients alive.
Host Flora Lichtman speaks with Dr. Fisher, now an emergency medicine physician at University Medical Center in New Orleans, about Hurricane Katrina and the vulnerability of our healthcare systems in the face of disasters.
Plus, science writer Maggie Koerth joins Flora to share other science news the week, including the link between heat waves and aging, updated COVID vaccine guidelines, the ancient origins of human mucus, and the possibility that dwarf planet Ceres could once have sustained life.
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Segment Guests
Dr. Erica Fisher is an emergency medicine physician at University Medical Center in New Orleans, Louisiana.
Maggie Koerth is a science journalist based in Minneapolis, Minnesota.
Segment Transcript
[MUSIC PLAYING] FLORA LICHTMAN: Hey, I’m Flora Lichtman, and you’re listening to Science Friday. Today on the show, we are looking back at one of the most devastating disasters in modern US history, Hurricane Katrina. 20 years ago today, it made landfall in Louisiana, and the levees designed to protect the city failed. Huge swaths of the city flooded. People were trapped in their homes, at their jobs, and in hospitals.
Around 1,600 people were inside Charity Hospital, the city’s only public hospital, as it flooded. One of the doctors there was Erica Fisher, a New Orleans local who was born in Charity. And when Katrina made landfall, she was a resident working in the emergency room. As the city flooded, she and her colleagues fought for days to keep their patients alive.
Dr. Fisher is now an emergency medicine physician at the University Medical Center in New Orleans. She’s here to reflect on Hurricane Katrina and the vulnerability of our health care systems in the face of disasters. Dr. Fisher, welcome to Science Friday.
ERICA FISHER: Thank you so much for having me.
FLORA LICHTMAN: Before we really get into it, what is this anniversary like for you?
ERICA FISHER: So this anniversary, it brings back so many painful memories about what the city went through during Hurricane Katrina. It also brings back memories of me being stuck at a hospital and unable to communicate with my family, who were also still in the city. So it’s so emotional for me to reflect on everything that happened during Hurricane Katrina.
FLORA LICHTMAN: Well, I appreciate you coming on the show to reflect with us today.
ERICA FISHER: Sure.
FLORA LICHTMAN: Katrina made landfall August 29, 2005. How did the day unfold?
ERICA FISHER: OK, so I was asked to be on the activation team, which is the team that usually respond and stay in the city during natural disasters. So I had to report to the hospital the Sunday prior to Hurricane Katrina because Hurricane Katrina made landfall that Monday. So I remember the Saturday before the hurricane came, I was at my mom’s house.
So she was packing. She was getting ready to evacuate the city with my brother. And the mood was really, really sad because she was really hurt that she had to leave me here in the city to weather out the storm. And we were almost in tears. I reported to work as usual, started my shift that night as usual. It’s just the atmosphere was very gloomy. This was before the storm made landfall to the city.
FLORA LICHTMAN: When did the flooding start?
ERICA FISHER: OK, so Hurricane Katrina made landfall that Monday. The rains were really, really heavy, and the winds were extremely strong. But then, after that, the rain stopped, you know? It stopped raining. And when it stopped raining, the flooding was only ankle-deep at the time. So I reported to work that Monday night, and we were all really happy because we thought that, OK, we’ll be home the next day. We didn’t see the true disaster that the hurricane caused at the time.
FLORA LICHTMAN: Right, because there was this delay, as the levees failed and then the water rose.
ERICA FISHER: Right. And then all of a sudden, the water started rising around the hospital. And we didn’t know why because we had no real form of communication at the time because all of our cell phones were not working. The water just started rising, and the hospital started flooding. The basement started flooding first, of course. And we didn’t how far up the water was going to rise. So the decision was made at the time for us to evacuate the first floor, which is where the emergency room was located.
FLORA LICHTMAN: That must have been so frightening.
ERICA FISHER: It was. It was so frightening because, again, we didn’t know what was going on in the city at the time. And to evacuate the first floor took a lot of teamwork because we had to transport hospital beds, medical supplies, and every single one of our patients to the second floor auditorium. So it was very, very frightening. But with teamwork, we made it happen.
FLORA LICHTMAN: Was there power, water? What services did you have?
ERICA FISHER: We had no power, and we had no water. It just so happened the generators of the hospital were located in the basement. And of course, the basement flooded first. So we had no power. Some kind of way, we were able to get power just only to that auditorium room that we were in, taking care of our patients. That was the only space that we had power.
FLORA LICHTMAN: You said earlier that you also weren’t able to be in touch with your family. Did you have family still in the city?
ERICA FISHER: I did. The majority of my family were still here in the city. And I’m from New Orleans. I grew up in the Lower Ninth Ward area of the city, which was the most devastated part of the city. And I still have family in the Lower Ninth Ward, and my dad was still here in the city. And I had no way of communicating with them to see how they were.
FLORA LICHTMAN: So you’re in the middle of this crisis in the hospital, where I’m sure your adrenaline is pumping, and meanwhile, you’re thinking about your family.
ERICA FISHER: Yes.
FLORA LICHTMAN: What was kind of keeping you going?
ERICA FISHER: I don’t know. I guess, the hope that my family would make it out alive because while I was working, I also got word that the levees breached, and the Lower Ninth Ward was flooding. They were finding dead bodies everywhere. The resident that said that didn’t realize that I was from the Lower Ninth Ward and that my family was still in the city. So when I got word that my area was devastated, was flooded, dead bodies everywhere, I truly broke down. That’s when I really broke down.
FLORA LICHTMAN: Did they make it through safely?
ERICA FISHER: Yes, thank God. Thank God they did. My dad sought rescue at a local church around his house, where he had to wade through the water to get to this church, where he was eventually evacuated from the church. My cousins, because below the interstate had flooded so badly, they ended up on top of the interstate for several days before they were rescued out of the city. So yes.
FLORA LICHTMAN: Wow. I’m glad they made it.
ERICA FISHER: Yes.
FLORA LICHTMAN: Safely.
ERICA FISHER: Yes.
FLORA LICHTMAN: How long were you and the patients trapped in this hospital without power and water?
ERICA FISHER: We were there for six days.
FLORA LICHTMAN: Wow. And was there a plan in place for what to do if there’s flooding and no power and no water? Or were you all sort of playing it by ear and improvising?
ERICA FISHER: Not that I’m aware of. There was no plan in place. I believe we were all just playing it by ear because when the hospital started flooding, the decision was made to evacuate the Emergency Department first floor. So I don’t think that was planned. I think that was at the spur of the moment type decision.
FLORA LICHTMAN: What happened to Charity Hospital after it was evacuated?
ERICA FISHER: After we left, we were evacuated from Charity Hospital. Charity Hospital was deserted. Upstairs was damaged because some of the windows burst during the storm. And again, the basement flooded. It was never reopened after the storm. No.
FLORA LICHTMAN: How did losing that hospital impact the residents of New Orleans?
ERICA FISHER: It significantly impact everyone because Charity was the safety net of the residents of New Orleans that did not have health insurance. The low-income residents, they didn’t have any access to good quality medical care when Hurricane Katrina damaged Charity Hospital. Charity was that hospital of the South that everyone talked about. So we lost. We lost something big. We lost Charity.
FLORA LICHTMAN: I think people don’t always think about how hospitals and health care might be made vulnerable by natural disasters. I think of a hospital as the safe place that you take people after the disaster has happened or during it, but not the casualty of the disaster itself. Do you have thoughts on that or can you reflect on that?
ERICA FISHER: When Charity started flooding, and we had to evacuate the emergency room, first floor to the auditorium, it just didn’t feel the same. We were the safety net for the city, and now we couldn’t let anybody in. We couldn’t take in any more patients because we had no place to put them nor take care of them. The emergency department is everything to the city. So when there was no emergency room to take care of people that were still here after Hurricane Katrina, it was just devastating to me.
FLORA LICHTMAN: What could have or should have been done differently, do you think?
ERICA FISHER: For starters, I think there should have been a clear plan on what to do just in case something this magnitude of a disaster would happen. Because as we know, New Orleans is prone to flood, you know? We get hurricanes. New Orleans floods sometimes.
FLORA LICHTMAN: Have hospitals in New Orleans learned from this experience? Are things done differently now in terms of preparation for flooding or extreme weather?
ERICA FISHER: I believe so. I think we have more disaster drills now in the event of any type of natural disaster, whether it’s flooding or any type of warfare. I think the design of University Medical Center also had that in mind. The emergency room is not on the first floor anymore. Just in case there is another type of flooding of the city, it’s on higher ground now. And I’m sure the generators are not located in the basement anymore.
[LAUGHTER]
FLORA LICHTMAN: I was going to ask. On this 20th anniversary, Dr. Fisher, what do you want people to know or think about?
ERICA FISHER: Let’s see. So Hurricane Katrina displaced a lot of residents of the city. It also displaced several of my family members. So I truly miss all of the crawfish balls that we used to have, all the family gatherings that we used to have prior to them evacuating and starting new lives. So I truly miss the sense of community that I once had prior to Katrina.
FLORA LICHTMAN: I think when people think about natural disasters and climate change, we don’t always think about this part of it. Not only the health care piece that we’ve been talking about, but how it changes the fabric of our lives, how it changes our communities.
ERICA FISHER: Right, right. Because it changed my community a lot.
FLORA LICHTMAN: Dr. Fisher, thank you so much for speaking with us today.
ERICA FISHER: Thank you so much for having me.
FLORA LICHTMAN: Dr. Erica Fisher is an emergency medicine physician at the University Medical Center in New Orleans.
[MUSIC PLAYING]
Coming up after the break, science writer Maggie Koerth is here to round up other science news from the week.
[MUSIC PLAYING]
Joining me now to discuss some of the other notable science news from the week is science writer and editor Maggie Koerth. Welcome back to Science Friday, Maggie.
MAGGIE KOERTH: Hi. Thanks for having me.
FLORA LICHTMAN: OK. We have been talking about Katrina, specifically its impact on health in New Orleans. But what about climate change? 20 years on, what have we learned from the storm? Has anything changed?
MAGGIE KOERTH: Yeah. I mean, yes and no. It’s been, like you say, 20 years since Katrina pushed storm surge through our New Orleans levee system. It flooded 80% of the city. It killed more than 700 people in just New Orleans alone. And that event has really shaped the way Americans think about climate disasters and how they happen.
You’re talking about rising risk, inadequate defenses, and then those social consequences of how police, media, and neighboring communities ended up vilifying survivors. And then the government and nonprofits failed those same people when they tried to rebuild their lives. There’s been change, but it’s not all been good.
FLORA LICHTMAN: What about sea level rise? What have we learned about that?
MAGGIE KOERTH: Well, there’s a couple of sobering studies out this month that suggest that climate risk and infrastructure failure parts of this equation are still a problem for New Orleans. So first off, researchers at Tulane compared 30 years of satellite data to climate models. And they found that sea rise projections that were made originally back in the mid 1990s have turned out to be remarkably accurate. In 1996, the IPCC models were projecting about 8 centimeters of sea level rise over the next 30 years. Satellites were directly measuring the height of the ocean in that same time period and found a 9 centimeter rise.
FLORA LICHTMAN: Wow.
MAGGIE KOERTH: Yeah, it’s a really big deal for climate science because those early models were pretty crude compared to what we have today. And there was just a lot less known, in particular, about how important ice melt in Antarctica and Greenland would turn out to be. So today, these satellites show that sea level rise is accelerating, and the models find a low confidence possibility that catastrophic ice sheet collapse could really inundate low-lying cities.
FLORA LICHTMAN: What about the levees? I mean, their failure was such a huge part of the Katrina disaster. Are walls and levees a sustainable strategy?
ERICA FISHER: Unfortunately, it’s looking like they aren’t. That’s this other story that has the more immediate risk for New Orleans. The Times-Picayune recently had a story reporting that the city’s $15 billion hurricane walls are actually sinking faster than the sea level is rising.
FLORA LICHTMAN: Oh, wow.
MAGGIE KOERTH: Yeah. In some parts of town, they’re sinking at a rate of 28 millimeters a year, which doesn’t sound like much, but you combine that with stronger hurricanes, higher sea levels, and it could really mean the difference between a bad storm and a deadly disaster.
FLORA LICHTMAN: In other climate news, there’s a story out this week about heat waves and their health effects.
MAGGIE KOERTH: Yeah, so there’s a large long-term study out of Taiwan that found that heat waves can age your body as much as smoking and drinking can. And this study is focusing on the ways that heat stresses your body and causes changes to your organs that are similar to what happens as you age. So it’s the kind of thing that can make you more susceptible to dementia, heart disease, cancer, diabetes, things like that.
This study followed more than 24,000 people between 2008 and 2022. And during that time, the researchers took samples, and they ran tests on these participants measuring things like inflammation, liver and kidney function, and blood pressure. There were about 30 heat waves that happened in Taiwan in those years, but people had different levels of exposure depending on factors like whether they lived in rural areas or worked outside. And the more heat wave exposure, the more the participants’ medical results showed signs of aging.
FLORA LICHTMAN: How much faster were they aging in relation to their exposure to heat?
MAGGIE KOERTH: Not a huge increase. We’re talking about less than a quarter of a year added to your biological clock for every 1.3 degrees Celsius extra that you’re exposed to. But again, this is a rate of aging that’s on par with things like regular smoking or drinking that we already take seriously as threats.
FLORA LICHTMAN: It’s been a chaotic week in DC health circles. Several leading scientists have been forced out or resigning at the CDC. And at the same time, at the FDA, there’s new guidance on COVID vaccines. What all is going on?
MAGGIE KOERTH: Yeah. So Robert Kennedy Jr. has announced new guidelines limiting who’s approved for COVID-19 vaccines. Previously, we were going on the emergency situation approval from when the pandemic was at its height. And he basically canceled that. So it’s going to be harder to get vaccinated if you’re under 65 and healthy.
FLORA LICHTMAN: In what way?
MAGGIE KOERTH: Well, for example, people who want a COVID vaccine this year are going to have to consult with their doctor first, most likely, instead of going directly to a pharmacy, like you’ve been able to do in the past. And it’s not clear what impact the decision by the FDA will have on things like whether your insurance covers your vaccine. And access could really end up depending a lot on the particulars of your doctor and what they choose to stock and what they choose to prescribe.
FLORA LICHTMAN: Will you need a prescription to get the vaccine?
MAGGIE KOERTH: Basically, what’s going on is that it’s becoming off-label use for anybody under 65 and healthy. And off-label use is legal, but it ends up making things more complicated. So doctors are allowed to keep saying people can get a vaccine, prescribing a vaccine to everyone. But some might not want to because there’s liabilities around off-label use. And because the guidelines are getting issued later than they normally do in the year, it’s not clear whether insurance is going to cover it yet.
FLORA LICHTMAN: So does that mean that if you have a condition that puts you at higher risk, you can get a vaccine just as easily as you could before if you were under 65?
MAGGIE KOERTH: It sounds like that is the case, yes. But what counts as high risk seems to be a little bit complicated. The FDA had a limited number of things that they were listing as increased risk. But the CDC is supposed to have its own list that’s not out yet. And that kind of adds to some of the confusion and chaos that’s happening.
And at the same time, you’re seeing things like different health agencies are signaling different policy. Medical societies like the American Academy of Pediatrics are issuing their own guidelines that are different from the FDA. And there’s a research group at the University of Minnesota who put out its own evidence report for fall vaccines that is also different from the FDA. So there’s just a lot of confusion about who is going to get listened to when it comes down to what doctors and pharmacies and insurance can and will do.
FLORA LICHTMAN: Yeah, that is so confusing for Americans to have to sort through.
MAGGIE KOERTH: It’s incredibly confusing.
FLORA LICHTMAN: Yeah. OK, let’s move back in time. Other health news, there’s a story about ancient mucus.
MAGGIE KOERTH: Yeah, so this is kind of interesting. There’s a study tracking the origins of a variant of MUC19, which is a gene that controls type, thickness, and location of mucus production. Now–
FLORA LICHTMAN: This is a good Halloween costume.
MAGGIE KOERTH: I know, right? [LAUGHS] It’s my costume. So this variant today is really common among people living in the Andes mountains in South America. And it turns out, though, that this gene variant got to humans through interbreeding that happened between Denisovans, Neanderthals, and us.
The assumption is that it would have had to get to humans at some point between 20,000 years ago or so in order to reach South America. And they found the exact same variant in Neanderthal skulls from Siberia that were about 50,000 years old. They’ve also found it in Denisovans. So it is just this really interesting thing where you can trace back that this probably originated in Denisovans, but it got passed around through several different human relatives before it got to us.
FLORA LICHTMAN: Following the snot trail through time, I love it.
MAGGIE KOERTH: Yeah, exactly.
FLORA LICHTMAN: Does everybody have this gene? Or do only some people have this gene?
MAGGIE KOERTH: This particular variant of a gene is pretty specific to people in South America. The gene exists all over, but this variant is a little bit more specific. And the fact that it’s common in South America, but nowhere else now suggests that the people who took it with them to that continent, it got some kind of protective benefit from it that you didn’t get from the people that stayed back in Asia.
FLORA LICHTMAN: If you have the variant of this gene, is your mucus different?
MAGGIE KOERTH: The study that I read did not say anything about how it necessarily made your mucus different, unfortunately. I was looking for that.
FLORA LICHTMAN: Standing by for that, information researchers.
MAGGIE KOERTH: Yeah, and standing by for that.
FLORA LICHTMAN: [CHUCKLES] OK, finally, something a bit more hopeful– news about a dwarf planet formerly known as an asteroid, but now a dwarf planet, Ceres.
MAGGIE KOERTH: Yeah, so Ceres is the largest object in our solar system’s asteroid belt. It’s not big enough to be a planet. It’s about a third of the width of Earth’s moon. It’s just this cold rock today. And back in the late teens, NASA’s Dawn spacecraft found salt deposits on the surface that had been left behind from a time long, long ago when water had bubbled up from underground on this thing. And so there’s a new study out now that is building on that work.
So today, Ceres’s water is only existing underground. It’s these briny ice deposits. But the researchers ran computer simulations to try to understand what it might have been like billions of years ago. And 2.4 to 4 billion years ago, there was probably enough radioactive decay happening inside Ceres’s core to generate heat, drive hydrothermal vents that brought the water up to the surface, and most importantly, create these kind of salty, wet mineral deposit soup places that life can potentially form, something similar to what you find at hydrothermal vents on Earth’s seafloor today.
FLORA LICHTMAN: So they found the conditions where life might arise. Do they have any other evidence that anything lived there?
MAGGIE KOERTH: No. So yeah, they found evidence that those conditions could have existed. But no one knows whether life did take hold right now, just that it’s possible that Ceres could have had those right ingredients for life at one point. But this is interesting because it does add evidence that some of these other smaller, now cold moons that you find around places like Saturn or Uranus could have had the same history.
FLORA LICHTMAN: Thank you, Maggie.
MAGGIE KOERTH: Yeah. Thank you.
FLORA LICHTMAN: Maggie Koerth, science writer and editor based in Minneapolis.
[MUSIC PLAYING]
Thanks for listening. Don’t forget to rate and review us wherever you listen. It really does help us get the word out and get the show in front of new listeners. Today’s episode was produced by Rasha Aridi and Charles Bergquist. But a lot of folks helped make this show happen every single week, including–
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FLORA LICHTMAN: I’m Flora Lichtman. Thanks for listening.
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About Charles Bergquist
As Science Friday’s director and senior producer, Charles Bergquist channels the chaos of a live production studio into something sounding like a radio program. Favorite topics include planetary sciences, chemistry, materials, and shiny things with blinking lights.
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Rasha Aridi is a producer for Science Friday and the inaugural Outrider/Burroughs Wellcome Fund Fellow. She loves stories about weird critters, science adventures, and the intersection of science and history.
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Flora Lichtman is a host of Science Friday. In a previous life, she lived on a research ship where apertivi were served on the top deck, hoisted there via pulley by the ship’s chef.