Lab Leak: Could Smallpox Come Back?

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A warning before we start, this cautionary tale discusses death by suicide. If you're suffering emotional distress or if you're having suicidal thoughts, support is available.

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Funeral director Ron Fleet is driving his van to a hospital in Catherine de Barnes, a quiet village in the countryside near Birmingham, England.

Catherine de Barnes is tiny, just a few dozen houses and a 19th century pub. To get to the hospital, you drive half a mile out of the village, down a narrow lane flanked by hedgerows and fields.

The hospital is a big old building in 20 acres of grounds. The year is 1978.

You might expect this to be a journey Ron Fleep knows well. Funeral directors do tend to become familiar with their local hospitals.
But no.

The hospital in the village of Catherine de Barnes hasn't seen a death for years.

It hasn't seen a patient for years.

It's an isolation hospital, kept empty but ready, just in case someone gets some appalling infectious disease that requires them to be confined safely away from the public.

Year after year after year, the hospital's husband and wife caretakers have kept a ward with 16 beds on constant standby, ready for patients who mercifully never came.

But now, they have had a patient, and she's died.

Ron Fleet assumes that the body he's come to collect will be in a morgue or a fridge. It isn't.
He's directed to a garage some distance away from the main hospital building.

In the garage, he finds a transparent body bag.

It's clear that this woman must have suffered terribly. Her body and face are covered with sores, scars and fluid-filled pustules.
And the body's on the floor, not a trolley.

How's he going to get it into his van?

He goes back to the main building to ask someone to help him. Nobody seems keen.

Fleet opens the back doors of his van and heaves the body inside.

Some kind of liquid sloshes around inside the transparent body bag.

I really hope this bag doesn't split, thinks Ron Fleet.

I'm Tim Harford and you're listening to Cautionary Tales.

By the 1960s, smallpox had become rare enough in England that when someone got it, it was often misdiagnosed. In 1966, for example, a young man called Tony became ill with what seemed flu.

Tony called in sick to his job as a medical photographer at the University of Birmingham and spent a few days in bed with aches and a fever.

Then came the rash. Tony thought he'd better get a doctor to look at it.
Maybe a sweat rash, said the doctor.

You'll have been sweating with that fever, or it could be a reaction to the medicine you've been taking. Anyway, nothing to worry about.

Tony starts to feel better, well enough to resume his social life.

He needs to freshen up a bit, so he borrows his dad's razor to shave. He's got to be careful, as he's still got that rash on his face, and oops, he accidentally slices through one of the pustules.

He goes to the pub with his dad and his girlfriend. The barman winces sympathetically.
Nasty attack of acne.

A week and a bit later, Tony's dad gets a spot on his face where he's nicked himself with the razor Tony borrowed. He then gets a fever and more spots.

An old man who'd been drinking in the pub gets ill too.

He infects his teenage grandson, who infects a hitchhiker he meets at a roadside cafe while on a trip to the beach a couple of hours drive away.

The hitchhiker gets home to another part of the country and infects his mum.

Various people go to doctors who say, probably flu or that looks like chickenpox.

It's eight weeks before someone sees a doctor who's seen smallpox before and says, hmm, let's test for that.

There are two types of smallpox. Variola major was the one you really didn't want.
It killed about 30% of those it infected. Variola minor was much less serious, but still no joke.

Its fatality rate was 1%,

comparable to COVID. Once the tests confirm that Variola Minor is at large, the medical authorities start to put the pieces together.
They find 73 people who've been infected. Luckily, nobody's died.

The medics trace back the roots of infection and they seem to converge on young Tony.

But where had Tony got it?

Well, smallpox might have been rare in England at the time, but it was still common enough in the Indian subcontinent.

The last outbreak of smallpox in Britain four years earlier turned out to have started with people recently arrived from Karachi.

Birmingham had a high rate of immigration from the subcontinent. Tony enjoyed a varied social life with friends from all backgrounds.

It was perfectly possible, as Tony's own case showed, to go out on the town while not realising you're infectious with a mild case of variola minor.

Most likely, Tony had picked it up from someone he'd met at a party.

The building at the University of Birmingham, where Tony worked as a medical photographer, also housed a laboratory that did research on smallpox.

The lab was run by a man called called Henry Bedson, a well-respected smallpox expert. Bedson had been cultivating strains of variola minor just over a week before Tony's symptoms started.

The incubation period for smallpox is typically between a week and a fortnight.

Quite a coincidence. Was it just a coincidence? Nobody seemed too worried at the time.
The university didn't feel the need to hold an investigation.

Tony's office wasn't even on the same floor as the smallpox lab, and everyone knew smallpox didn't spread that easily. It needed both close personal contact and a dose of bad luck.

Think about the outbreak Tony started. Yes, it passed it on to a few people, but he met many more who didn't get infected.
In eight weeks, only 73 people had picked it up.

The idea that virus particles might have found their way out of Bedson's lab and wandered around the building, missing everyone else until they met Tony on the floor above, seemed fantastical.

Still, the coincidence was striking. It occurred to Bedson's boss, the head of the department, that he should probably get an outside opinion.

He asked another smallpox expert to visit the university and check that Bedson was taking adequate precautions. All looks perfectly standard, said the expert.
Same as any other smallpox lab.

By 1978, 12 years later, Henry Bedson has moved up in the world. He's still at the University of Birmingham, but he's now the head of Department of Medical Microbiology.

He's 48 years old, married with three young kids. He looks like a a stereotypical academic scientist.
Bald, softly spoken, tweed jacket.

With his new departmental duties, Edson no longer has time to be so hands-on in his old smallpox lab. But he has a PhD student doing research, and that research is important.

In those 12 years, much has changed. Smallpox is no longer common on the Indian subcontinent, or indeed, anywhere.
It's been wiped off the face of the earth.

Teams of workers led by the World Health Organization have been visiting the furthest flung villages of the world's poorest countries, persuading people to be vaccinated, tracing contacts where they find a case.

Henry Bedson himself has been involved. The WHO sent him to Afghanistan and Pakistan as part of an expert committee.
And all that hard work has has succeeded.

It's been eight months now since the last report of a case of smallpox anywhere in the world.

That case was in Somalia. It looks likely to go down in history as the very last time any human gets this terrible disease ever.

But what if there was a way smallpox might come back?

What if there was a similar virus lurking in some some population of wild animals, liable to cross over to humans at any time?

Smallpox, after all, like many human diseases, originally came from animals. Maybe camels, maybe gerbils, it's not entirely clear.
And two recent discoveries were troubling Henry Bedson.

Researchers in the Netherlands and Russia had found a virus that looked very much like smallpox, lurking in samples taken from wild monkeys and rodents.

This new mystery virus had become known as white pox. But what was whitepox? How exactly did it differ from the various strains of variola major? Might it pose a threat to humans?

These were the questions Henry Bedson had his PhD student investigating. But Bedson had a problem, because the WHO was worried about another way smallpox might come back.

What if it leaked from a lab? Plenty of labs around the world, like Bedson's, were working on smallpox viruses.

The WHO wanted to restrict all future research to just a handful of labs that would meet more stringent new safety standards. Bedson's lab was not on the list.

Henry Bedson wrote to the World Health Organization, Can I have a few more months to finish up my whitepox research? My lab's been scaling down. I promise I'll be done by the end of the year.

Bedson was arguably being economical with the truth.

The lab had scaled down compared to a few years ago, it had just one PhD student now, but in the hope of completing his whitepox work before his lab had to close, Bedson had just scaled up his stocks of smallpox, taking delivery of 22 new samples of different strains of the virus.

The World Health Organization wrote back.

Okay, then, just until the end of the year. Bedson was relieved.
And then, one evening in August at home, his phone rang. It was a doctor he knew calling from the hospital.

Henry,

said the voice, I've got a patient here with a suspected case of smallpox.

Cautionary Tales will be back after the break.

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Everybody knows Shaq, but off camera, he's just a regular guy. People never believe me when I say I'm just like them.

I take out the trash, do dishes, and I struggle with moderate obstructive sleep apnea or OSA. And a lot of adults with obesity also struggle with moderate to severe OSA.

You know those scary breathing interruptions during sleep? The loud snoring, choking, and daytime fatigue? I knew I had to talk to my doctor. Don't sleep on the symptoms.

Learn more at don't sleep on OSA.com. This information is provided by Lilly, a medicine company.

By 1978, young Tony has left his job as the medical photographer at the University of Birmingham. There's a new photographer now, working on the floor above Henry Bedson's smallpox lab.

Her name is Janet Parker, and she's 40 years old. On the second Friday in August, Janet begins to feel unwell.
A few days later, she starts to get a rash. She sees a doctor.
Chickenpox?

She also has cystitis. and the doctor prescribes antibiotics for that.
A couple of days later, the rash is much worse. She sees a second doctor.
Maybe an allergic reaction to the antibiotic?

He prescribes a different antibiotic. Days go by, and Janet's condition gets worse and worse.
She sees a third doctor. This doctor calls the infectious diseases unit at the hospital.

I don't think it's chickenpox, she says. But I'm stumped.
Can one of your infectious disease specialists visit her home and take a look?

We don't do home visits, say the hospital. That's the policy.
Well, unless it's smallpox.

No chance of that, says Janet's doctor. She hasn't been out of the country for five years.

The hospitals send an ambulance, and Janet is admitted to the infectious diseases unit. The specialist there takes a close look at Janet and makes some notes.

Vesicular rash, most pronounced on the face. Lesions half a centimetre.
White fluid.

More advanced lesions with darkened centers.

No lesions in the mouth. Febrile.

Question mark.

Drug reaction?

Then,

question mark, question mark, question mark, variola?

The doctor consults her colleagues. It can't be smallpox.
But they're sufficiently puzzled to want to rule it out. The trouble is, none of them have experience with smallpox.

They've only seen it in textbooks. But they still have access to a designated regional smallpox consultant, a doctor who's worked in Bangladesh and knows the disease.
They find his number.

It's 7.30 in the evening. and the regional smallpox consultant is about to open a bottle of wine at home when his phone rings.

He doesn't get many calls like this, maybe once a year, but he doesn't mind because he gets a fee for every call out.

So far, it's always been either a bad case of chickenpox or an allergic reaction to a drug. He puts his wine aside, drives to the hospital, finds Janet's room and

that

looks like smallpox.

But who is this woman? And how on earth has she got smallpox in Birmingham eight months after the world's last recorded case in Somalia? The doctors fill him in on Janet's details.

She works as a medical photographer at the University of Birmingham.

The consultant, of course, knows all about the smallpox lab at the university. He'd better call Henry Bedson.

Henry, he says when Bedson answers the phone, I've got a patient here with a suspected case of smallpox. It's a lady who works as a photographer at the medical school.

At the other end of the line, Henry Bedson is too stunned to speak. The consultant takes a sample of the fluid from Janet's pustules.
and drives to the medical school to meet Henry Bedson.

Together, the two men open up the lab and put the slide under the microscope. Bedson looks first.

Without a word, he moves aside to let the consultant see.

There's no doubt, it's smallpox. They'll need to run more tests to confirm that it's variolar major and find out exactly which strain.

Bedson sets the tests in motion. The regional smallpox consultant picks up the phone and makes the call that he's never had to make before.

Open up the isolation hospital at Catherine de Barnes.

As the fictional Dr. Dufenschmirz might put it, If I had a nickel for every time a medical photographer at the University of Birmingham got smallpox, I'd have two nickels.

Which isn't a lot, but it's weird that it happened twice.

Back in 1966, when Tony got smallpox, it had seemed ludicrous to think that the virus might have gone walkabout from Henry Bedson's lab around the building.

But soon after, in 1970, a young man in Germany developed fever and a rash a week and a half after flying home from a backpacking trip to Karachi.

With that travel history, German doctors suspected smallpox right away. They put the man in strict isolation.

Still, somehow, 17 other people in the hospital developed smallpox, including patients two floors distant who never left their room.

How?

One explanation was that smallpox might be more capable of airborne transmission than had previously been thought.

Investigators set off a smoke device in the room where the man had been and tracked how the smoke wafted into the corridors, up the stairwells and into other rooms.

The results mapped pretty well onto the pattern of infections.

At the University of Birmingham, Henry Bedson and his colleagues stand in the courtyard outside the medical school. They're checking how close the photographer's office is to the smallpox lab.

Not very close. They're at least 40 feet apart.
If the virus particles wafted through the air to Janet, it's far from obvious what route they might have taken.

By now, various authorities are competing to take the situation in hand. One insists that everyone who has anything to do with the smallpox lab has to go into quarantine, including Henry Bedson.

That seems like overkill. Bedson's been thoroughly vaccinated, and if he'd got smallpox at the same time as Janet Parker, he'd have known about it long before now.

Still though, Bedson's told, stay at home. You can't be too careful.
Another authority insists that the smallpox lab be immediately fumigated to kill any virus particles that might be lingering.

Only afterwards do they realise this means they've killed the samples from Janet Parker that Bedson had been testing to identify which strain of smallpox she'd got.

They'd better get another sample while they still can.

At the hospital in Catherine de Barnes, Janet is still, just about, clinging to life.

They call the smallpox lab at the University of Liverpool and ask one of the professors to drive the 100 miles to Birmingham to visit Janet and take samples back for testing.

We'll arrange a police escort, of course, they say.

As the professor leaves the motorway near Birmingham he's met by a policeman on a motorcycle who leads him through the city and down the quiet country lanes to the 20 acre site of the hospital at Catherine de Barnes.

The policeman thinks his job is done and says farewell.

The professor is confused. Wait, you're leaving me here?

But surely the whole point of a police escort is to get me safely back to my lab when I'll have highly contagious samples of smallpox in my car?

Now the policeman's confused. Nobody's told me anything about that, sir.
All the way back to Liverpool? I finished my shift at five o'clock.

At five o'clock, they're still gridlocked in central Birmingham. The policeman waves goodbye.
Screw this, thinks the professor.

He decides to give the rush hour traffic time to clear and detours into the suburbs to call in at the home of his old friend, Henry Bedson.

Bedson is not coping well with quarantine. He hates being holed up at home when he could be doing something to help.

The phone keeps ringing and he keeps thinking he'd better answer it in case it's important.

But it's always some journalist trying to get him to admit that he's to blame for all the chaos that's unfolding in the city.

the desperate search to trace and quarantine and vaccinate anyone Janet Parker might have met.

Bedson's friend tries to lift his spirits. But the next morning, Bedson writes a note.

I'm sorry to have misplaced the trust which so many of my friends and colleagues have placed in me and my work, Bedson writes.

I realize this act is the least sensible thing I have done. but it may allow my wife and children to get some peace.

Bedson calls to his wife.

I'm just going to the garden shed.

Cautionary Tales will be back in a moment.

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Everybody knows Shaq, but off camera, he's just a regular guy. People never believe me when I say I'm just like them.

I take out the trash, do dishes, and I struggle with moderate obstructive sleep apnea, or OSA. And a lot of adults with obesity also struggle with moderate to severe OSA.

You know those scary breathing interruptions during sleep? The loud snoring, choking, and daytime fatigue? I knew I had to talk to my doctor. Don't sleep on the symptoms.

Learn more at don'tsleeponosa.com. This information is provided by Lilly, a medicine company.

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Henry Bedson is still alive when his wife finds him in the shed, though he's losing a lot of blood. She runs back to the house.

As she's about to pick up the phone, it starts to ring.

Local radio news, can I speak to Professor Bedson? Get off the line, yells Bedson's wife. She slams the receiver down and picks it up again.

No, it's the wife. She says she wants us to get off the line.

Henry Bedson survives for five days on life support before doctors conclude that he won't recover.

Five days after that, Janet Parker's life finally ebbs away. away.

Funeral director Ron Fleet is sent to collect her body. Janet is cremated.
Then they fumigate the crematorium just to be safe.

Janet Parker has infected only one other person,

her mum.

Once her mum recovers, Humanity is once again free from smallpox. But if it's going to stay that way, it might help to find out

how had Janet got it?

The government appointed a committee to investigate.

They tried the same kind of test as in the German hospital, setting off a smoke device in the smallpox lab to understand where the airflow might go.

The smallpox lab was a small inner room connected to a larger outer lab. If the door between those rooms was open, the air from the smallpox lab could get into the outer lab.

And the door was open sometimes, because the smallpox samples were stored in that outer lab.

But if smallpox particles got loose in that outer lab, it shouldn't pose a risk. Everyone who was allowed into the outer lab had been vaccinated against smallpox.

But a little bit of the smoke drifted further, some beyond the outer lab and into a corridor, and some into a service duct, and from the service duct through a badly fitted access panel into a room on the floor above.

Not Janet Parker's office, another room used for storage, but that also had a telephone with an outside line.

Janet Parker's office phone didn't have an outside line, so when she needed to make orders for supplies of photographic materials, she'd use the phone in that storage room, sitting close to the badly fitted panel.

The investigators determined that Janet had placed an unusually large number of orders on the last Tuesday in July, two and a half weeks before she began to feel ill.

That timeline doesn't quite stack up. The usual incubation period for smallpox is one to two weeks, not two and a half.
And you can query how relevant that German hospital really is.

There, you had a young man with smallpox coughing up clouds of virus particles.

Here, you had a lab with workers trying carefully to minimize contamination.

Still, the investigators conclude, infection through the service duct is the most probable route that they could find.

Armed with the investigators' report, a government agency decides to sue the University of Birmingham for failing to ensure health and safety at work.

In his book, The Last Days of Smallpox, the author Mark Pallin describes the case in detail. Witness after witness attests that Henry Bedson was known for being meticulous about safety procedures.

You can't eliminate all risk from lab work.

As one expert witness says, perfection is impossible. But Henry Bedson's smallpox lab was doing nothing untypical by the standards of the time.

What about the pox in the ducts hypothesis? The university's lawyer calls a professor to testify for the defense.

I've been doing some calculations, the professor says.

Based on how much smoke made it from the smallpox lab into the room with a telephone and how many virus particles typically get into the air from routine lab work.

I reckon you might expect virus particles to make it into the telephone room at the rate of one particle every two to twenty thousand years.

The lawyer for the Health and Safety Agency calls an expert witness too, but it seems that he hasn't researched his experts' views.

When asked about the investigator's theory that Janet had got the virus through the service duct, the expert says he thinks it's highly implausible.

The lawyer's taken aback. His own witness has just dismissed the central plank of his case.
But if we discount the duct hypothesis, the lawyer asks, with what does that leave us?

The expert replies,

It leaves you with a puzzle.

Say the words lab leak now, of course, and the city that springs to mind isn't Birmingham, it's Wuhan.

A novel coronavirus pandemic just happens to start in a city which has a lab that does research on novel coronaviruses. Quite a coincidence.
Was COVID a lab leak?

That debate rumbles on.

But I wondered if the Birmingham story might give us any general lessons about lab leaks.

I think there are two. Lesson number one,

the puzzle might never be solved. We might only ever have competing stories and our own best guess as to which makes most sense.

The second lesson starts with another observation from that trial. Perfection is impossible.
No matter how careful you try to be, there'll always be something you might overlook.

Think about that evening before Henry Bedson despairingly went to his garden shed.

Bedson's at home,

forced to quarantine, because you can't be too careful. But parked outside on his drive is his friend's car, containing highly dangerous smallpox samples from Janet Parker.

The professor then drives his car 100 miles up the motorway with no police escort. What What if it had a crash?

Or think about fumigating the crematorium after Janet Parker's body was burned, just to be safe.

Yet nobody had thought about the risk to funeral director Ron Fleet, who had to lug Janet's corpse into his van without help, praying the body bag wouldn't burst.

There'll always be something you might overlook.

In 2014, in a lab in Bethesda, Maryland, half a dozen glass vials of smallpox were discovered in a cardboard box at the back of a cupboard, forgotten since the 1950s.

If we're going to do research on deadly viruses, we have to accept some risk that something will go wrong in some way we hadn't considered. So the second lesson I want to suggest is this.

We'd better be damn sure that that research is worth it.

Perhaps in the case of Birmingham, the puzzle has an answer. In 2018, the author, Mark Palland, tracked down the lawyer who'd represented the university in the court case.

The lawyer was now 85 years old. The author asked, do you know what really happened?

Well,

said the lawyer. There was a rumor.
A very strong rumor. I could never get anyone to say it on the record.
But the rumour went like this.

Back in the 1970s, remember, nobody had smartphones or digital cameras. To take holiday photos, you needed rolls of film, and they were pricey.

A photographer at an institution, like the medical school, could buy those films in bulk at a discount.

There was a well-established tradition in the medical school, the rumor went, that the photographer would get you cut-price films.

That might explain why Janet was placing so many orders in the last week of July, just before everyone went on their summer holidays.

And what if a few days later, Janet had gone around the building delivering to her colleagues the supplies she'd got for them?

What if she'd popped into the outer lab just for a moment to drop off a roll of film?

What if this year she'd chosen just the wrong moment when there were virus particles in the air or on a surface she happened to touch?

It's only a rumor, just one more competing story.

But if Janet had encountered the virus a few days after the investigators guessed, it would make the incubation period line up.

And if the tradition of photographers delivering film to their colleagues went back to young Tony, that would also neatly solve the two-nickel question of why an infection might have happened twice.

There's one more loose end to tie up. One final irony.
Was the research worth it?

Henry Bedson, remember, had been anxious to complete his work on white pox, the mysterious virus from labs in the Netherlands and Russia.

If white pox was similar to smallpox, it might live in wild populations of monkeys and rodents and then jump back to humans.

After Bedson's death, other researchers finished the job. They found that whitepox was a mirage.

These viruses weren't just like smallpox, they were smallpox. And the smallpox didn't come from the animals.

The samples from rodents and monkeys in the Dutch and Russian labs had been contaminated with smallpox in the labs themselves. The monkeys and rodents had never had a pox-like virus at all.

That kind of contamination shouldn't happen in a lab, of course, but sometimes it does. Perfection is impossible.

If the work in Henry Bedson's lab had been perfect, Janet Parker could never have got smallpox.

But if the Dutch and Russian labs had been perfect, Bedson wouldn't have been doing that work in the first place.

A key source for this episode was Mark Pallan's book, The Last Days of Smallpox, Tragedy in Birmingham. For a full list of our sources, see the show notes at TimHarford.com.

Cautionary Tales is written by me, Tim Harford, with Andrew Wright, Alice Fiennes, and Ryan Dilley. It's produced by Georgia Mills and Marilyn Rust.

The sound design and original music are the work of Pascal Wise. Additional sound design is by Carlos San Juan at Brain Audio.
Ben Nadaf Haffrey edited the scripts.

The show features the voice talents of Melanie Guttridge, Stella Harford, Oliver Hembrah, Sarah Jopp, Masaya Monroe, Jamal Westman and Rufus Wright.

The show also wouldn't have been possible without the work of Jacob Weisberg, Bretta Cohn, Sarah Nix, Eric Sandler, Carrie Brody, Christina Sullivan, Kiera Posey, and Owen Miller.

Cautionary Tales is a production of Pushkin Industries. It's recorded at Wardore Studios in London by Tom Berry.
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and now superhuman shack.

I keep telling them not to say that. I'm no superhuman.
Believe it or not, I struggle with moderate obstructive sleep apnea, or OSA.

In adults with obesity, moderate to severe OSA is a condition where breathing is interrupted during sleep with loud snoring, choking, gasping for air, and even daytime fatigue.

Let's just say it can sound a lot like this.

Sound familiar? Learn more at don't sleep on OSA.com. This information is provided by Lilly, a medicine company.
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Hey, Ryan Reynolds here, wishing you a very happy half-off holiday because right now Mint Mobile is offering you the gift of 50% off unlimited. To be clear, that's half price, not half the service.

And Mint is still premium unlimited wireless for a great price. So that means a half day.
Yeah? Give it a try at mintmobile.com slash switch.

Upfront payment of $45 for three months plan equivalent to $15 per month required. New customer offer for first three months only.
Speed slow out of 35 gigabytes of networks busy.

Taxes and fees extra. See mintmobile.com.
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