Revenge of the Miasma

Summary

Radiolab Episode Summary: "Revenge of the Miasma"

Radiolab, hosted by Lulu Miller and Latif Nasser, embarks on an intriguing exploration of the hidden life in the air and the historical clash between miasma theory and germ theory. In the episode titled "Revenge of the Miasma," released on February 28, 2025, the hosts engage in a compelling conversation with acclaimed science writer Carl Zimmer, delving into the fascinating and often overlooked history of aerobiology.

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1. Introduction to the Conversation

The episode opens with the camaraderie between hosts Latif Nasser and Lulu Miller as they prepare to discuss a captivating story with Carl Zimmer. Latif recounts bringing Carl into the studio unexpectedly to explore a "beautiful but terrifying and arguably kind of urgent story."

[01:24] Carl Zimmer: "Oh, wait, you're listening."

[02:28] Carl Zimmer: "So you probably have never heard of Fred Meyer."

2. The Forgotten Pioneer: Fred Meyer and the Birth of Aerobiology

Carl Zimmer introduces Fred Meyer, a young plant pathologist from 1915 who stumbled upon a mysterious fungus killing watermelons. Meyer's groundbreaking discovery led him to coin the term "aerobiology," the study of life in the air—a concept unheard of at the time.

[03:02] Carl Zimmer: "Fred Meyer, he started out as what he described as a watermelon doctor."

Meyer’s innovative experiments involved attaching petri dishes to biplanes to capture airborne microbes, revealing that fungi could travel through the atmosphere to infect plants miles away.

[04:07] Carl Zimmer: "Goes through the air. It sends up spores that travel around to get to new fruit."

3. The Disappearance of a Visionary

Meyer's pioneering work attracted governmental support, leading to his first major expedition on a commercial flight across the Pacific. Tragically, the plane vanished, and with it, the nascent field of aerobiology faded into obscurity.

[06:58] Carl Zimmer: "He's on one of the first commercial flights that's going across the Pacific. It never gets there. There's a huge search. The US Navy just goes scouring the Pacific for days."

4. Revisiting History: Miasma vs. Germ Theory

Latif and Carl traverse back 2,500 years to Hippocrates, who first proposed that "miasmas" or "corrupted air" caused diseases—a belief that endured until the Enlightenment brought forth germ theory. Despite the emergence of germ theory in the 1600s, miasma supporters like Max von Pettenkofer resisted the paradigm shift, famously demonstrating his conviction by drinking cholera-infected broth without succumbing to the disease.

[14:20] Latif Nasser: "Oh, wow."

[14:29] Carl Zimmer: "He was like, no, this is miasmas. I will drink cholera soup."

5. The Skagit Valley Chorale: COVID-19's Airborne Transmission Case Study

Fast-forwarding to March 2020, the episode highlights the Skagit Valley Chorale outbreak, where a rehearsal led to widespread COVID-19 infections despite adherence to CDC guidelines. This event underscored the limitations of prevailing public health strategies that dismissed airborne transmission.

[23:04] Carl Zimmer: "There are starting to be reports of it in Washington state."

[24:30] Latif Nasser: "This group is called the Skagit Valley Chorale, and this is one of their rehearsals."

6. The Revival of Aerobiology and Modern Implications

Carl Zimmer discusses how historical resistance to airborne disease transmission delayed critical responses during the COVID-19 pandemic. His book, Airborne, unearths the forgotten scientists who recognized the potential for diseases to traverse vast distances through the air, a revelation that only gained traction decades later.

[07:44] Carl Zimmer: "This is the story of this amazing science that has been trying to get off the ground for centuries."

[29:19] Carl Zimmer: "It's like the idea of miasma was, in a lot of ways, really, really wrong."

7. The Aerobiome: A Hidden World Above Us

Exploring the concept of the aerobiome, Zimmer reveals a vibrant ecosystem teeming with bacteria, fungi, and viruses that inhabit the clouds and atmosphere. These microorganisms not only travel across continents but may also play beneficial roles in human health and the environment.

[30:30] Carl Zimmer: "There are lots of bacteria in the clouds... They are eating the clouds."

[33:21] Carl Zimmer: "I think that there is a lot of life there that we just don't know about yet."

8. Conclusion: Bridging Past and Present Understanding

The episode culminates in reflecting on the intertwined histories of miasma and germ theories, emphasizing the importance of embracing a more nuanced understanding of airborne diseases. The resurgence of interest in aerobiology promises to reshape public health approaches and our perception of the invisible life that surrounds us.

[29:18] Carl Zimmer: "The germ theory is, in many ways, really, really right... It does seem like in that swinging away from the old ideas, people started to jump to conclusions that maybe went too far."

[34:57] Latif Nasser: "Carl's book is called the Hidden History of the Life We Breathe. And it is truly, it's so beautiful."

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Key Takeaways

• Historical Perspectives: The long-standing belief in miasma theory profoundly influenced public health policies for centuries, often hindering advancements brought by germ theory.

• Aerobiology's Potential: Understanding the aerobiome opens new avenues in disease prevention, environmental science, and human health, highlighting the complexity of airborne ecosystems.

• Relevance Today: The COVID-19 pandemic serves as a pivotal moment that underscores the necessity of revising outdated health guidelines to accommodate the realities of airborne transmission.

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Airborne by Carl Zimmer emerges as a pivotal resource, unraveling the intricate history and modern implications of diseases that traverse the skies. This Radiolab episode not only sheds light on forgotten scientific endeavors but also calls for a reevaluation of how we understand and interact with the life-filled air around us.

Transcript

[Latif Nasser]

Radiolab is supported by Dell.

[Lulu Miller]

Dell Technologies is celebrating with anniversary savings on their most popular tech. For a limited time only, save on select next gen PCs like the XPS 16, powered by Intel Core Ultra processors and more. Plus curate your dream setup with great deals on select monitors, mice and more. Must have electronics and accessories. When you shop [e-mail] deals you'll have access to leading edge technology to match your forward thinking spirit and free shipping on everything A Again, that's Dell.com deals.

[Latif Nasser]

Radiolab is brought to you by Progressive Insurance. Do you ever find yourself playing the budgeting game? Well, with the name your price tool from Progressive, you can find options that fit your budget and potentially lower your bills. Try [e-mail], progressive Casualty Insurance Company and affiliates. Price and coverage match limited by state law. Not available in all states. Radiolab is supported by the John Templeton foundation, funding interdisciplinary research and catalyzing conversations designed to inspire awe and wonder. Dive deeply into the wonders of the [e-mail].

[Lulu Miller]

Listener support WNYC Studios.

[Carl Zimmer]

Oh, wait, you're listening.

[Latif Nasser]

Okay.

[Carl Zimmer]

All right.

[Latif Nasser]

Okay.

[Carl Zimmer]

All right. You're listening to Radio Lab Radio from wnyc.

[Latif Nasser]

Back in the chair. Latif.

I'm so excited we finally get to do this together. Hey, it's Latif Nasser and Lulu Miller and this is Radiolab. Hey. Welcome back.

Thank you.

Remind me, what were you doing this whole time?

I was rearing a small baby.

Right. Yeah.

I was on maternity leave.

Okay. So. Creating life, it sounds like. That's.

Yeah, I was learning to juggle. Cause now it's. Now there are three, so you gotta always have one in the air.

But you were also, as I was to learn. Scheming.

Scheming for new episodes. I came back on day three. I actually looked back, it was day three. And I. Because I had gotten wind of a beautiful but terrifying and arguably kind of urgent story. And so I dragged you into the studio totally unprepared.

That's true.

To meet with one of our favorite Radiolab guests.

[Carl Zimmer]

Hi, guys.

[Latif Nasser]

Hey.

Carl Zimmer. Your ears must have been burdened right now.

[Carl Zimmer]

What have people been saying about me now?

[Latif Nasser]

Carl Zimmer, the sort of prima ballerina of science right now.

The best.

[Carl Zimmer]

This is great. Thank you so much.

[Latif Nasser]

He is a columnist for the New York Times. He's written all these gorgeous science books and he has been working on a news story that is awesome. All on your turf. It is history of medicine and I do not think you know it.

Really.

And it begins with a man Named Fred Meyer.

[Carl Zimmer]

So you probably have never heard of Fred Meyer.

[Latif Nasser]

No, never.

[Carl Zimmer]

So Fred Meyer, he started out as what he described as a watermelon doctor.

[Latif Nasser]

Okay, this was in 1915, by the way.

[Carl Zimmer]

So he was a plant pathologist. And he was actually in college, like working one summer down in Washington, D.C. and he noticed this huge pile of rotten watermelons next to it, a boxcar.

[Latif Nasser]

And when he cracked them open, he noticed they weren't rotting in, like, the normal way. They were weirdly black and crazily slimy.

[Carl Zimmer]

And, you know, this is the kind of thing he studies. So he takes some of the watermelons in his arms back to the lab, and he actually discovers a fungus that is killing them. And this is actually a new to science. So like, so he discovers his own disease. He's like 18 or 19.

[Latif Nasser]

Wow.

[Carl Zimmer]

And so then he starts to, like, think about, well, how does this fungus get from one watermelon to another?

[Latif Nasser]

So he starts looking for this disease out on watermelon farms in the fields, and he starts noticing that it can jump from one watermelon to another, even if they aren't next to each other. So pretty quick, he realizes this fungus.

[Carl Zimmer]

Goes through the air. It sends up spores that travel around to get to new fruit.

[Latif Nasser]

Now, at the time, every scientist, and honestly, every 4 year old knew that things like dandelion seeds and pollen can float through the air. But the idea that living things could travel through the air and stay alive long enough to infect plants but make them sick, that was totally new to Meyer. So he started to wonder, like, how far can these things travel?

[Carl Zimmer]

Like, how high do they go?

[Latif Nasser]

You mean how high, like up into the air?

[Carl Zimmer]

Yes. So he builds these, like really crazy, crude devices, basically sticks like a petri dish onto a stick, and he starts getting in airplanes.

[Latif Nasser]

This is the early 1930s, so we're talking little people, propeller planes, you know, with the pilot seat open to the air.

[Carl Zimmer]

And he gets into these, you know, open cockpits with his little petri dishes on a stick, and he's just hanging them out in the air, you know, in these biplanes.

[Latif Nasser]

Wow.

[Carl Zimmer]

You know, people think he's crazy. You know, he goes on blimps and he's sticking these things out from the gun on blimps, and the blimp crew are like, what are you doing? But. But he's catching stuff.

[Latif Nasser]

He catches microbes that usually live down on the earth on potatoes and lettuce and celery, another that ferments cheese, another that was known to kill tre all Floating around thousands of feet up in the air.

[Carl Zimmer]

Then he finds out that Charles Lindbergh and his wife Anne are going to be flying across the Atlantic. Charles Lindbergh designs a special instrument to hold out of his plane to catch things, and he does.

[Latif Nasser]

Wow.

[Carl Zimmer]

Over Greenland, over the Atlantic, he's catching all sorts of stuff.

[Latif Nasser]

He attaches his device to balloons that are being sent up into the stratosphere.

[Carl Zimmer]

And 12 miles up, he catches stuff.

[Latif Nasser]

All these invisible, tiny little creatures floating around alive in the air, around us, but also miles up into the atmosphere. And eventually, because of all this stuff.

[Carl Zimmer]

He'S finding, he's actually able to persuade the government, the U.S. government, that they should basically, like, open up a bureau for this life in the air.

[Latif Nasser]

And he actually coins a term for this whole field.

[Carl Zimmer]

He calls it aerobiology, which no one's heard of before. But just like the government is supporting a weather service, he wants to basically have an aerobiology service.

[Latif Nasser]

Like, it would be like, these bugs are in the air today. Like, watch out for the. Is it that kind of thing?

[Carl Zimmer]

That would be one thing he was ultimately open for. Yeah.

[Latif Nasser]

What?

[Carl Zimmer]

And the government agreed to this.

[Latif Nasser]

Wow.

[Carl Zimmer]

In 1938, they were like, yes, go for it. So for his first big expedition for this grand new project, which he's now finally getting paid for, he gets on one of the first commercial flights that's going across the Pacific.

[Latif Nasser]

Right.

[Carl Zimmer]

He's very excited. He gets on board the plane that's supposed to get to Manila. It never gets there. There's a huge search. The US Navy just goes scouring the Pacific for days. This is all in the news. No one ever found the plane. So he disappears, and basically this brave new science of aerobiology kind of disappears with him.

[Latif Nasser]

Wow.

[Carl Zimmer]

In less than a year after he coined the name aerobiology, the freaking founder.

[Latif Nasser]

Of aerobiology disappears into thin air.

[Carl Zimmer]

Yeah. And in some ways, it seems almost cursed.

[Latif Nasser]

So this is why I wanted to talk to Carl, because he actually just wrote a book. Can you describe the COVID Yes.

[Carl Zimmer]

It's got a. A groovy yet sinister rainbow cloud on it.

[Latif Nasser]

That's right.

The book is called Airborne, and it's all about this whole other layer of life that lives up there in the air.

[Carl Zimmer]

This is the story of this amazing science that has been trying to get off the ground for centuries.

[Latif Nasser]

A field that, despite a trail of other scientists like Meyer, who saw with clear evidence how alive and sometimes dangerous the air could be, just wasn't able to break through until. Well, until a moment in very recent history when millions of Lives were on the line.

[Carl Zimmer]

Yeah. And I just was trying to. Trying to wrap my arms around it with this book.

[Latif Nasser]

And what Carl found was this eerie history of ideas. Ideas that were wrong for the right reasons and right for the wrong reasons. And a terrible and complicated truth somewhere in the middle.

[Carl Zimmer]

Yeah. And it's a long, crazy story.

[Latif Nasser]

We're here for it. We got some popcorn.

How far back do we go?

[Carl Zimmer]

I think we do have to go back, you know, 2,500 years to Hippocrates.

[Latif Nasser]

Okay, so we're in Greece. This is a couple hundred B.C. and Hippocrates, in addition to being, you know, do no harm, Hippocratic oath guy, was supposedly one of the first to argue that diseases might not be coming from angry gods trying to punish you, but rather from nature itself.

[Carl Zimmer]

Hippocrates developed a really powerful concept that if you look at these different diseases that people got, they got them because they breathed in bad air. Hippocrates would refer to it as a miasma.

[Latif Nasser]

What is like the cliff's notes of how he saw them? Are they just like bad vibes?

Smoke monster, ghosts?

[Carl Zimmer]

Yeah, it was a corruption. Think of it as a corruption of the air. So corrupt air, you know, it might smell bad. You know, marsh water could give off fumes or even a rotting corpse. You know, the alignment of planets might also somehow disturb the air.

[Latif Nasser]

And while that may seem silly to us now, it was a very useful.

[Carl Zimmer]

It seemed to work. And so classical medicine really just sort of took up miasmas just as a fact.

[Latif Nasser]

And it's not a bad idea. I mean, you get it. Like, you see a whole town at the same moment getting a thing.

I live in LA right now, post wildfire. Everyone is afraid of, like, random bits of ash or asbestos or lead or whatever just randomly in the air. And I get how miasmas could really feel real. Cause right now they kind of do.

[Carl Zimmer]

Right. So in a way, that kind of stretchiness of the miasma idea helped it to just last a really long time.

[Latif Nasser]

And which kind of diseases did. Did this account for?

[Carl Zimmer]

Like, it seems like everything. I mean, it's just a long, long list of diseases that Hippocrates and then later people would ascribe to miasmas.

[Latif Nasser]

Wasn't it like malaria? It's like bad area. Like, it's like from bad air.

[Carl Zimmer]

Right, right, right. So malaria got its name in the Renaissance, I believe, in Italy. This was an ide. Various forms really like took hold and it worked.

[Latif Nasser]

And this was the central belief for what caused disease for about 2,000 years. Then comes the Enlightenment. And you've got all kinds of new ways to investigate the world and think about what counts as evidence and great new ways of literally seeing the world.

[Carl Zimmer]

So in the 1600s, people are inventing the first microscopes, and they're looking through the microscopes and they're seeing all these tiny little things squirming around these animal, these germs. And this starts to give some people the idea that, hey, like, these might be things that make people sick.

[Latif Nasser]

Basically, this is the birth of germ theory. But at the time, the bad air people thought this was ridiculous.

[Carl Zimmer]

This is just dreaming. You are just letting your imagination run wild. Where. Where's your actual proof? You're. You're seeing these things through a microscope. Then there are these people dying of the plague. You haven't shown us that any bacteria are causing that plague. And so authorities just brushed away the germ theory of disease, decade after decade after decade.

[Latif Nasser]

So this debate of, hey, I think it's in the germs. No, it's in the air. I think it's in the germs. No, it's in the air that goes on and on and on with the germ theory. People building up more and more evidence and the air people, the miasma people just shouting them down. Until the late 1800s.

[Carl Zimmer]

In the city of Hamburg, in 1892, there was an outbreak of cholera.

[Latif Nasser]

You know, terrible. People turning blue in the face, collapsing in the street, dying by the thousands.

[Carl Zimmer]

And all the medical authorities in Hamburg, they were all big believers in miasma. So it's 1892, and people in charge are still treating this like a miasma. And there was this bleeding figure in terms of public health named Max von Pettenkofer. He was incredibly famous and everyone took his opinions incredibly seriously.

[Latif Nasser]

And his view was that cholera was caused by fumes coming out of the ground.

[Carl Zimmer]

And so you just needed to make sure that the ground was clean and then these fumes wouldn't come into people's houses and give them cholera.

[Latif Nasser]

Meaning, like clean of garbage.

[Carl Zimmer]

Yeah, garbage, waste. And so people were saying, hey, this is what von Pettenkofer says. And everyone followed what he said.

[Latif Nasser]

Now, on the other side, you've got this German doctor named Robert Koch. He was a germ theorist, and his argument was that, no, cholera was not in the air. It was a bacteria moving through the water that people were drinking.

[Carl Zimmer]

But Pettenkofer, he kept resisting it, saying, no, cholera is not spread through the water. He just refused to believe it. Like, no, no, no, it's not the water. It's not the water. No.

[Latif Nasser]

Spoiler alert. It was the water. But Pettenkofer was so sure of himself.

[Carl Zimmer]

He actually asked Robert Koch for some of the cholera bacteria from Hamburg, and he had it prepared in a tube, and he had a bunch of his followers in front of him and he drank it.

[Latif Nasser]

Oh, wow.

That was the strength of his conviction of, no, this is miasmas. This is the air. I will drink cholera soup.

[Carl Zimmer]

Yes. Yeah. There's this amazing line he wrote later. He said, even if I had deceived myself and the experiment endangered my life, I should face death calmly, for it would not be as a thoughtless and cowardly suicide. I should die in the cause of science like a soldier on the field of honor.

[Latif Nasser]

Wow.

Wow.

[Carl Zimmer]

And, well, he survived. And he talked about it.

[Latif Nasser]

He survived.

Like, how did he survive that?

[Carl Zimmer]

Well, so, I mean, the awkward fact is that a lot of people who get infected with cholera don't get that sick. And it turns out that Robert Koch's colleagues who gave him the bacteria kind of had an idea of what he was gonna do. And so they actually. They actually took their sample from a patient who had had a very mild case. Oh.

[Latif Nasser]

Cause they didn't want him to die.

[Carl Zimmer]

That's what they said later.

[Latif Nasser]

That's so nice of them.

[Carl Zimmer]

Yes. But he didn't know it. So after he recovered, he wrote a note to Robert Koch. He said, Herr Dr. Pettenkofer has now drunk the entire contents and is happy to inform Herr Dr. Professor Koch that he remains in good health. So I think that was a little screw you moment.

[Latif Nasser]

Yeah.

[Carl Zimmer]

But with this terrible outbreak in Hamburg.

[Latif Nasser]

Once Robert Koch comes on the scene with his germ theory ideas, he supplies.

[Carl Zimmer]

Clean water to people. He has buildings cleaned out, and they stopped the cholera outbreak.

[Latif Nasser]

Wow.

It was a clear message that this disease did not come through the air, did not travel in the air. It was bacteria in the water.

[Carl Zimmer]

And, you know, Robert Koch says, okay, Germany as a whole needs to deal with diseases like this from now on. This way, we're done with miasmas. It's all germ theory. Now, when the germ theory of disease won out, all these different diseases that had been thought to be spread through the air just by miasmas turned out to have nothing to do with that. So malaria, you mentioned, that's not bad air. That's mosquitoes. Rigworm. Not spread by fumes, but instead by ordinary skin contact. Syphilis.

[Latif Nasser]

Not caused by corrupt air, but by.

[Carl Zimmer]

A kind of bacteria transmitted only by sex. Vibrio and Salmonella came from contaminated meat or water. The rabies virus required the service of live animals which bit their victims. Jail fever proved to be caused not by prison air, but by lice borne bacteria. Rats carried fleas infected with Yersinia pestis.

[Latif Nasser]

And that, not the air, is how people got the plague.

[Carl Zimmer]

And so you just had this whole long list of diseases where microbiologists in the late 1800s would definitively prove were.

[Latif Nasser]

Caused by germs, not the air.

[Carl Zimmer]

Didn't seem to them like there was anything left for the air. You, I mean, you literally, like have these public health authorities at the time saying things like a patient's breath is free of germs, just flat out forget the air.

[Latif Nasser]

And that basically became medical dogma for the next century. But here is what I love about Carl's book is that he finds this whole mostly forgotten history, this, this trail of scientists who are piling up evidence that, okay, yeah, germs can cause disease, but also germs can travel through the.

[Carl Zimmer]

Air, laying out very clearly that people can potentially get each other sick with all sorts of diseases through the air over long distance.

[Latif Nasser]

So in the early 1900s, you've got our watermelon guy, Fred Meyer, doing his thing with plant diseases. But then there are these other stories of other scientists who were taking that idea and extending it to human disease. And many of them, like Meier, disappearing over the ocean would end up being mostly forgotten.

[Carl Zimmer]

So you do not know who William and Mildred Wells are.

[Latif Nasser]

So, so around the time that Meyer is flying around with Lindbergh, this married scientific duo, William and Mildred Wells, take.

[Carl Zimmer]

A cream separator, something you'd separate cream from milk.

[Latif Nasser]

Yeah.

And they figure out a way to kind of MacGyver it into a device.

[Carl Zimmer]

Glass cylinder called the Wells air centrifuge.

[Latif Nasser]

That would spin around and in so doing separate out and capture bacteria and viruses in the air.

[Carl Zimmer]

Yeah. And so, and then they go on.

[Latif Nasser]

Or at least William goes on to like show this in animals too. Right? To show transmission. Airborne transmission, yeah.

[Carl Zimmer]

Yeah. So William gets busy in his lab building something that the newspapers call the infection machine. Basically what he does is he has a chamber, kind of a big bell jar, and he can put animals in there, he can put mice in there, he can put a rabbit in there, and he can create these mists of disease, influenza or tuberculosis, and he is able to show that these animals just inhaling this stuff get sick.

[Latif Nasser]

Now, even at that time, scientists knew that diseases could be carried by a cough or whatever, you know, travel, maybe Five, six feet. But the Welles were discovering something very different from that.

[Carl Zimmer]

These were not, you know, big droplets that were, you know, shot out of someone's mouth when they sneeze and then just dropped to the ground. These were droplets that had to float, aerosols, sometimes people call them, which could.

[Latif Nasser]

Travel and cause disease over much, much larger distances.

[Carl Zimmer]

And so the fact demonstrating that these things could get so far was that was quite something which, like, feels like.

[Latif Nasser]

That should be revolutionary in that moment. Like that feels like it should be massive, scary. Big important news for public health for a lot of people.

[Carl Zimmer]

You know, a lot of other scientists and doctors were very skeptical. It did not help that.

[Latif Nasser]

Why, why, why is everyone still so confident? Germs don't go through the air.

[Carl Zimmer]

It's, it's, I think it's one of the hardest things to figure out, like why people don't recognize something that's just out there. And, you know, and I would, you know, I. This way, the Wells enemies were not stupid. They just would look at the evidence differently. They would have different kinds of thresholds for what would convince them what, you know, what is going to make them step away from just, you know, generations of what people are taught in medical school.

[Latif Nasser]

And also, Carl says, I mean, just think about the practical public health side, the implications of if this were true. The idea that disease is just everywhere in the air is very daunting.

[Carl Zimmer]

You know, A lot of the guidelines for staying healthy, very individual based, you know, here's what you as an individual should do, right? Just stay a few feet away from people who look sick. If you have a cough, cover your mouth. But, you know, if it's all in the air around us.

[Latif Nasser]

Yeah, yeah.

[Carl Zimmer]

You know, you have to think differently.

[Latif Nasser]

So the findings about the air that Wells and this trail of other scientists were seeing through the 30s and 40s and 50s, they just never quite took hold.

[Carl Zimmer]

It was all hidden knowledge. I mean, these people were almost entirely forgotten.

[Latif Nasser]

And then some 70 years later, we would all go through the painful process of finally learning to think differently. Thanks in part to a song that's coming up after this break.

All right. Okay, here we are. Latif, Lulu, Radiolab.

We're back with Carl Zimmer.

[Carl Zimmer]

Yes.

[Latif Nasser]

Who started us way back over 2,000 years ago, but is about to bring us up to the very recent past.

[Carl Zimmer]

Yeah, so on March 10, 2020, a group of about 60 people come into this church on the outskirt of Skagit Valley in Washington. They set up chairs, somebody closes the door, the heater is Running for a while, and it shuts off, and they start to sing.

[Latif Nasser]

This group is called the Skagit Valley Chorale, and this is one of their rehearsals. Now, the people in this chorus, many of whom were retired, they knew about the sort of early spread of COVID.

[Carl Zimmer]

There are starting to be reports of it in Washington state. So they did take precautions.

[Latif Nasser]

People who had symptoms like sneezing or coughing stayed home. Those that came kept their distance from one another as much as they could. They sanitized surfaces in the room. They washed their hands. So they were following all of the CDC guidelines at the time, and they.

[Carl Zimmer]

All thought, we're doing what the Centers for Disease Control have been telling us to do, so we should be okay. But a couple days later, some of them start to feel terrible.

[Latif Nasser]

Most of the 60 people in the room that day got sick.

[Carl Zimmer]

Just, boom, just in that one rehearsal. And a couple, three people ended up in the hospital, and two of them died.

[Latif Nasser]

And soon it was all over the news. As one of the earliest, really big spreading events.

[Carl Zimmer]

This little singing group in a corner of Washington state suddenly became internationally famous.

[Latif Nasser]

But for the people who were there.

[Carl Zimmer]

That day, they said, how can this be happening? We did everything we were supposed to. It's not like we were all, you know, hugging each other, and we weren't sneezing on each other. We were just singing. Yeah. And people who were 40ft away from each other were getting sick.

[Latif Nasser]

But that feeling of disconnect, says Carl, was actually a symptom of the way experts and public health officials were thinking about COVID in those first few months.

[Carl Zimmer]

In March 2020, when these singers got sick, you actually had public health authorities saying explicitly, Covid is not airborne.

[Latif Nasser]

Focus was on staying home if you were sick. You know, wiping down surfaces, washing your hands.

[Carl Zimmer]

And that is all really based on this idea that a disease like the flu is spread in big droplets that, you know, you wipe your mouth or your nose, you smear it on a doorknob, or maybe you cough, and you, like, cough right in someone's face. And so that was it. And, you know, I, as a reporter, was trying to make sense of this disease. Like, if we all were. Did you wipe down your groceries?

[Latif Nasser]

Yeah, totally.

[Carl Zimmer]

Me too. And, you know, I would. I would tell people, like, yeah, wash your hands, wash your hands. And I even went on Radiolab and said, you should all wash your hands, because that's one of the great classic ways to stop the spread of infection. And that's true.

[Latif Nasser]

I helped produce that episode. I still stand by that episode. That Was great.

[Carl Zimmer]

Yeah, you definitely still wash your hands. But. But you can't assume that washing your hands will keep you safe from an entirely new. And we had to learn the hard way. And it. I mean, I, you know, I can remember actually going to have dinner with friends and, you know, I just said, I'm not gonna hug you, I'm not gonna shake your hand. You know, I was trying to be, you know, good and careful and any mask on. Of course not.

[Latif Nasser]

Right. Yeah.

[Carl Zimmer]

It was ridiculous. In hindsight, you know, we sat down, you know, after putting on this big show of not making contact, we sit down and we talk. Like, you know, knowing what I know now, I think, wow, I was endangering my friends lives. If you're sitting indoors across a dinner table and having a long, lively conversation. And if you have Covid, they could get Covid too. You don't have to sneeze on them. You don't have to drink from the same glass. You just talk or sing or breathe.

[Latif Nasser]

Right.

Now, of course, by spring 2020, there were scientists arguing that Covid had to be airborne. You know, that it could travel further than just droplets from a sneeze or a co. But it took a really long time for that idea to be accepted.

[Carl Zimmer]

And it wasn't just taking a long time. People were yelling at each other, and the World Health Organization was saying, cut it out. You know, Covid is not airborne. Like, everything was very strong, opposite poles. And I just thought, what? What is going on? Like, why is it so hard? And I didn't appreciate just, you know, all the history behind this.

[Latif Nasser]

And now that he does, Carl blames miasmas in a way, or the fact that germ theory was born largely in opposition to the idea that the air could carry sickness. Once that idea had been debunked, it took its place alongside spontaneous generation or the idea that the earth was flat as foolish ideas that science had debunked, which made it really hard for the occasional bits of evidence that there was life in the air to break through.

[Carl Zimmer]

You know, I would talk to people who, you know, I talked to Anthony Fauci. I said, what happened? And he's like, well, look, you know, you just have to understand, like, this is what we were taught in medical school. This is what we were all taught. We just didn't take airborne infection seriously. You know, he learned a hard lesson in Covid, and he admits that.

[Latif Nasser]

And interestingly, one of the things that finally brought medical health professionals around was what happened at the Skagit Valley Corral.

[Carl Zimmer]

Yeah. So There were a few scientists who said, folks, this might be airborne. And one of the things that they did was that they got in touch with the Skagit Valley Chorale because it looked from the news reports like this might be a classic case of airborne transmission. And so they actually collaborated with the singers, and they tried to reconstruct what had happened. And, you know, how is the air moving that night in the church? So some of these scientists published a paper on this case, and it turned out to be some of the most compelling evidence that Covid can be airborne.

[Latif Nasser]

Wow. I never knew that second act of the story.

Feels like the story you're telling. It's like a story of two orthodoxies, two ways to explain how and why we get sick that are both kind of right.

[Carl Zimmer]

You know, the idea of miasma was, in a lot of ways, really, really wrong. And a lot of people may have died because of it. And the germ theory is, in many ways, really, really right, and a lot of people's lives have been saved. But it does seem like in that swinging away from the old ideas, people started to jump to conclusions that maybe went too far or at least left.

[Latif Nasser]

Us all with a blind spot.

[Carl Zimmer]

I mean, I sometimes imagine, like, if we had glasses where we could see, like, living things in the air, we might think differently. So we've been talking a lot about, you know, living things coming out of our noses and our mouths. But, you know, things get into the air in all sorts of ways. Like, if you go to the beach and you're looking at the waves, like, every time those waves crash, they send up tiny bubbles of seawater, some of which have bacteria and algae. So if you're walking along the beach, you would see just these plumes of living things, like, rising up, blowing onto land, or going up higher into the sky. If you take a walk in the woods, you would see all this stuff streaming out of the soil. You would actually see lots of bacteria and fungi and things actually coming off of the leaves on the trees. You know, there would be all this stuff that you would recognize as being constantly, like, pumped up into the air all the time from everywhere.

[Latif Nasser]

Are there things that, like, play out their whole life up there? Are there dramas and worlds and existences up there in the aerobiome?

[Carl Zimmer]

Well, so, you know, there are lots of bacteria in the clouds. Okay. And they're actually possibly eating the clouds.

[Latif Nasser]

What?

What?

[Carl Zimmer]

They are eating the clouds. There's organic matter in the clouds, and it's possible that bacteria can find just enough of that stuff to swallow up to Grow very, very slowly. But to grow and maybe even to divide in the clouds.

[Latif Nasser]

Weird.

[Carl Zimmer]

You know, when it rains, it's not just raining water, it's raining lots of bacteria as well.

[Latif Nasser]

How far has, like, how far has something been seen to travel in terms of a germ or a bacteria or something that could cause human illness?

[Carl Zimmer]

There's a terrible disease called Kawasaki disease that affects children. A really harsh disease with kids. They have very strong immune reactions. Their tongue turns the color of strawberries. And kids will get terrible heart damage from this disease. Kawasaki disease. And that may kill them later. Nobody has found the germ that causes Kawasaki disease. It seems like it's caused by some kind of germ, but no one has found it yet. But what they have found is that in Japan, flare ups of Kawasaki disease seem to correlate with strong winds and dust coming from China. Whoa. And we get Kawasaki disease in the west coast of the United States. And those cases seem to correlate with the weather patterns going across the Pacific.

[Latif Nasser]

My God. With a wind current coming all the.

[Carl Zimmer]

Way from China, all the way from China. Maybe. Yeah, Maybe there's some fungus or some other living thing that gets kicked up with the dust in China and then gets picked up by the wind and then just keeps going thousands of miles.

[Latif Nasser]

All the way across the ocean. Still alive enough to maybe.

[Carl Zimmer]

Yeah, still capable of killing a child.

[Latif Nasser]

Oh, my God.

[Carl Zimmer]

You'll see sometimes these amazing maps of the world's weather, you know, seeing, you know, clouds moving along and low pressure and high pressure systems and so on across the whole planet. Aerobiologists would like to do that for life. They would like to create a global map in motion showing how living things are moving around the world in the air. That is a dream that they are.

[Latif Nasser]

Working on, I guess. My. I have one, like, big last question for you, Carl. This concept of the aerobiome and a world up there in the clouds or up high, I mean, what else could be in there? Can you just kind of give us the profile? Like, you know, we've got aquatic worlds and Earth world and like, what else is up there?

[Carl Zimmer]

I think that there is a lot of life there that we just don't know about yet. Even in the microbial world, when microbiologists, like, are capturing microbes in the air, they tend to find totally new species. These are species they just didn't know about. And so, you know, with viruses and bacteria, fungi, there's just a huge diversity of things up there that we don't know about.

[Latif Nasser]

Young scientists wanting to make a name for yourself. Go to the air.

[Carl Zimmer]

Totally go. Absolutely, absolutely. Go to the air. Yeah. And I don't want people to like, leave the book saying like, okay, that's it. I'm never breathing again. We probably actually get some benefit from breathing the aerobiome. It just, you know, you just want to be breathing in the living things in say, like forests, for example. And, you know, our, our immune systems might actually be primed to have kind of a partnership with these things that we breathe. I mean, some of them, we breathe it in and it ends up in our lungs or in our gut and just stays there. Like we breathe in stuff and some of it just stays. And maybe these are partners that we need.

[Latif Nasser]

Thank you, Lulu, for dragging me into that interview. It was a real breath of fresh air. I feel like you actually can't say that on public radio.

Terry Gross's domain. Well, yes, thank you for joining me in the conversation and for everyone listening, Carl's book is called the Hidden History of the Life We Breathe. And it is truly, it's so beautiful. It is full of so many more stories you didn't know and really gorgeous writing around the chorus, around all kinds of stuff with COVID his own lack of understanding and learning, and it's just, it's gorgeous. Airborne. Go check it out.

Even though it doesn't have wings, it's floating to a bookstore near you. This episode was reported, honestly. It was reported by Carl Zimmer in his book, but it was reported and produced by Sara Khari and fact checking by Natalie Middleton.

Thanks so much for listening. See you next week.

Bye.

[Rachel]

Hi, I'm Rachel and I'm from Norshopping, Sweden. And here are the staff credits. Radiolab was created by Jad Abhirade and is edited by Thorn Wheeler. Lulu Miller and Latif Nasser are our co hosts. Dylan Keefe is our director of sound design. Our staff includes Simon Adler, Jeremy Bloom, Becca Bressler, W. Harry Fortuna, David Gable, Maria Paz Gutierrez, Sindhu Nyana Sambandan, Matt Kielty, Annie McKeown, Alex Neeson, Sara Khari, Sarah Sandbach, Anissa Vitza, Arian Wack, Pat Walters and Molly Webster. Our fact checkers are Diane Kelly, Emily Krieger and Natalie Middleton.

[Latif Nasser]

Hi, this is Charlie Liu calling from El Pescadero, Mexico. Leadership support for Radiolab's science program is provided by the Gordon and Betty Moore Foundation, Zion Sandbox of Simons Foundation Initiative and the John Templeton Foundation. Foundational support for Radiolab was provided by the Alfred P. Sloan Foundation. WNYC Studios is supported by Carnegie hall, which presents the American Composers Orchestra, featuring works by Alice Coltrane and Tonya Leon and premieres by Edmar Castaneda, Clarice Assad and more. March 10th.

[Ira Flatow]

[e-mail] this is Ira Flato, host of Science Friday. For over 30 years, the science Friday team has been reporting high quality science and technology news, making science fun for curious people by covering everything from the outer reaches of space to the rapidly changing world of AI to the tiniest microbes in our bodies. Audiences trust our show because they know we're driven by a mission to inform and serve listeners first and foremost with important news they won't get anywhere else. And our sponsors benefit from that halo effect. For more information on becoming a sponsor, visit sponsorship.wnyc.org.