Explained (2018–…): Season 2, Episode 7 - The Next Pandemic - full transcript

Let's imagine, for a second,
all the ways the world could end.

It could be something from above.

Or something from below.

Or it could be something
we did to ourselves.

But there's one thing
that consistently ranks

as one of the most likely things
to end the world...

Well, if you think of anything
that could come along

that would kill millions of people,

the pandemic is our greatest risk.

A pandemic is a disease
that escapes our control,

sweeping across the world,



killing millions
and changing civilizations.

We know this
because we've seen it before...

a few times.

In the 6th century, a pandemic killed
half the world's population.

In the 14th,
another wiped out half of Europe.

And in the 20th, a pandemic killed

almost five percent of
the world's population in just two years.

But that was a hundred years ago.

We've learned from these past pandemics
and made incredible advances.

Improved response, improved training,
improved workforce...

We have improved surveillance systems,
improve communications.

We have organizations
like the World Health Organization, CDC...

We have improved diagnostics,
improved drugs, therapeutics, vaccines.

And yet the risk of it
happening again has never been higher.



We've done the math on this.

We estimate there are about five new
emerging diseases happening

somewhere on the planet every year,

and that rate is accelerating.

So it is inevitable that they
will become pandemics.

Mother Nature
is the ultimate bioterrorist.

We're in a race,
and the stakes couldn't be higher.

This simulation estimates that a pandemic
today could kill 33 million people

in just six months.

In terms of a death toll, a pandemic would
rival even the gigantic wars of the past.

The economy will shut down.

The cost to humanity will be unbelievable,
and no country will be immune

from the problem this will create.

So the question is not,
is the next pandemic coming...?

There are only three things
that are inevitable in this world.

Death, taxes, and flu pandemics.

Or... when is the next pandemic coming?

We estimate there are around
one and a half million viruses in wildlife

that we don't yet know about.

Any one of those could be spilling over
into the human population right now.

The question is...

will we be ready for it?

Influenza pandemics
must be taken seriously.

The world is fighting
the worst Ebola epidemic in history.

The stakes couldn't be any higher.

A virus can be just as destructive
as a bomb or a missile.

Pathogenic organisms recognize
no boundaries lines.

Residents believe their town
is ground zero for the swine flu epidemic.

All sorts of animals
may be the culprits.

A sick person can be healed,

but in the meantime,
he spreads the disease.

The campaign
against infectious disease can succeed

only if the public cooperates.

We just don't know
what the future is going to hold.

Pandemics begin
in a world invisible to the naked eye.

Microbes were likely
the first living things on earth.

Many can't replicate on their own,

so they hijack other living cells.

And today they're all around us.

And on us.

And in us.

Many arrive in peace, but others damage
or kill our body's cells.

Fever, coughing, sneezing, diarrhea...
that's our body fighting back.

But some are so strong,
they can overwhelm our immune system...

and kill us.

Pandemics are mainly caused
by two types of microbes:

bacteria and viruses.

The interesting thing about viruses
is they are supremely adapted to jump

from one species to another.

They're the most likely microbes
to become the next pandemic.

As you can probably guess,
viruses that cause bird flu

come from birds.

Swine flu comes from pigs.

HIV came from chimpanzees.

Ebola likely comes from bats.

And several diseases
come from mosquitoes.

When these spill over to humans,
the new virus is called a zoonotic virus

and they're extremely dangerous.

These are viruses which mutate rapidly
and therefore change the surface

and evade immune responses quickly.

They can transform into a new virus
once they get into the human population.

Now those don't happen all the time.

They're quite rare events.

But when they do,
the effects can be devastating...

which brings us to a farm
in Kansas a century ago.

Experts aren't certain, but they believe
the 1918 flu pandemic could have started

when an infected bird
and an infected human

met the same pig.

The bird had bird flu,
a type of influenza virus that have been

infecting chickens, geese and ducks
for at least a hundred years.

While the person had a different
influenza strain, the seasonal flu

that had made humans feel stuffed up
and feverish for centuries.

The two viruses couldn't infect
each other's species,

but they could both infect pigs.

And in one pig cell,
those two viruses combined,

creating a new zoonotic virus: H1N1.

These parts from the human virus
gave it the ability to infect humans,

but these parts from the bird virus
prevented immune systems

from recognizing it
and effectively fighting back.

A deadly combination.

It killed somewhere between 50 and 100
million people around the world.

It was unlike anything else in history.

You can think of a disease
on two scales:

how contagious it is
and how deadly it is.

Here is the seasonal human flu

while this is the bird flu.

And this is the 1918 combination.

It was so contagious
because it was airborne,

meaning the virus could hang in the air,
infecting anyone who inhaled it.

And a 1918, it infected one
in every three people on Earth.

Then it killed almost 5%
of the world's population.

The final ingredient was human technology.

This flu emerged in the middle
of the first World War.

We were sending people
across from the U.S. into Europe for war

and then we were bringing them back.

So this virus exploited
those travel patterns

and spread around the world
very quickly and very effectively.

In fact,
in every past pandemic,

human technology is responsible
for taking diseases around the world.

The Black Death arrived in Europe
on ships in the 14th century.

It was two distinct diseases:

Bubonic plague, which killed
as many as 60% of the people who got it.

And pneumonic plague,
which killed almost everyone who got it.

Then there was smallpox.

It was less deadly than the Black Death,

killing 30% of the people who got it,
but it was more contagious.

Humans spread it around the world.

In the 20th century alone,
it killed around 400 million people.

These other diseases
have also become pandemics.

But eventually, we developed technology
that could defend us.

The practice of isolating travelers
for a time to see if they were infected,

now known as quarantine,

was first developed
during the Black Death.

Then we invented microscopes,

allowing us to see the enemy
for the first time.

Next, we developed antibiotics.

These made these diseases
spread by bacteria far less deadly.

And smallpox led to the development
of the first ever vaccine

which defends us against some viruses.

The way a vaccine works is we get
injected with proteins from the virus

and we create our own antibodies.

These are little molecules that attach
to those proteins and neutralize the virus

and allow it to be swept out of the body.

So when we get infected by a real virus,
we can rapidly create an immune response,

send out these antibodies,
and get rid of the virus.

If enough people
in a population get vaccinated,

it's almost impossible
for the disease to spread.

So smallpox was declared eradicated
in 1980.

And these diseases don't cause
nearly the amount of deaths they used to.

And antiretroviral drugs have made viruses
like HIV far less deadly and contagious.

Finally, the internet is helping us detect
and contain diseases earlier.

This is why studies show that fewer people
are contracting infectious diseases today.

But at the same time,
the number of outbreaks is increasing,

and that is largely
because of emerging zoonotic viruses.

Out of an estimated 1.6 million
unknown viruses in wildlife,

we currently know of about 3000.

So it's really less than .01%.

That means the next pandemic

could be a virus
that we're not prepared for.

We know some pretty lethal ones,

but we expect that there are
others out there that are more lethal,

that are better at being transmitted,

where we've got no drugs and no vaccines.
They're the big risk.

This is called Disease X.

And we know we're unprepared
because we've seen them before.

This is a wet market
in the Lianghua, China.

Unlike markets in much of the West where
animals are already dead when they arrive,

this wet market sells meat
that's very fresh.

It's killed on sight.

That's what makes it a Disease X factory.

Many different animal species
are stacked on top of each other,

their blood and meat mixed,
before being passed from human to human.

All the while,
their viruses are mixing and mutating,

increasing the odds that one
finds its way into humans...

which is likely what happened at a market
here in southern China in 2002.

Back then, some wet markets in China
sold wild animals

like snakes, civet cats, and bats.

And demand for them was high.

On November 16th,
a man in Foshan, China got sick

after preparing a meal
of chicken, cat, and snake.

He had the symptoms of pneumonia.

Fever, cough, and trouble breathing.

When treatments for pneumonia didn't work,

Chinese officials reported it
simply as "atypical pneumonia."

But then it started spreading.

And people started dying.

There were reports of clusters
of respiratory infections

in hospitals in China.

But we're used to that.
There were strains of influenza virus

that caused flu in Asia many times over.

Um... and we always noted them
and there was always concern,

but they were not
particularly scary to us.

But people like the CDC
and the World Health Organization

start to take notice
of these rumors of illness

and went to the Chinese government
and asked, "What is going on?"

And the way that the world found out
about it is that someone

from one of those towns
decided to go to Hong Kong.

Hong Kong was
a uniquely bad place for this to happen.

In 2003, Hong Kong was home
to about seven million people.

Over 16 million tourists
visited each year,

and over 500 international flights
took off and landed there every day.

On February 21st, one man arrived.

He was already feeling sick.

He checked into the Metropole hotel

and headed up to his room
on the 9th floor.

There, he threw up or coughed,

spewing droplets
all over the elevator and hallway.

That's how he infected 16 people

who would spread the disease
around the world.

The man in this room
boarded a flight the following day,

arrived in Hanoi, Vietnam,
and checked himself into the hospital,

where he infected doctors and nurses.

One of those doctors
then took the disease to Bangkok.

That's when the World Health Organization
declared an international emergency

and officially named the disease.

Severe acute respiratory syndrome.

Or SARS for short.

A few days later,
scientists found the cause:

a virus they had never seen before.

Back at the Metropole,
a woman in this room

flew home to Toronto and died.

Her son checked himself into the hospital.

I remember sitting there,
my kids were there,

and I was watching the news
and all of a sudden I saw

a picture of my hospital,
Mount Sinai Hospital, on the news.

That was the first time it hit home
that this was going to be a problem.

It was about a week later
when we identified

that there were a substantial number
of staff at the hospital

who were also ill with SARS.

Who's going to be on call on Tuesday?
We have to get somebody else.

What was their job?
Who's going to fill in for them?

Sometimes just losing one
senior resident in our department

throws the whole department into chaos.

I was feeling fine when I got home,

but I woke up in the middle of the night
not feeling well with a fever and...

then I knew that was probably what I had.

By late March,
47 hospital staff were sick in Toronto

and hundreds more were in quarantine,

including Allison.

This was one of the scariest things
about SARS.

It's early symptoms were subtle
and hard to identify,

causing outbreaks
even in advanced hospitals.

Back in Hong Kong,
a nightmare was taking place.

SARS was spreading faster than ever.

A man with SARS was in this unit
of an apartment complex.

He had diarrhea
and when he used his toilet,

the SARS virus was carried
through the pipes to the unit below

where a fan blew the virus
back up into the building's ventilation

and into the apartments above.

Then the wind was likely blowing the virus
to nearby buildings,

making it much more difficult to contain.

That's truly a nightmare scenario.

You're not physically in contact
with a known infected person.

So it's much harder to track
because we don't necessarily know

the source of the contamination
or the infection.

In total, 329 people were
infected in this apartment complex

and hundreds were quarantined.

By now the world was panicking.

The fear that dogs and cats
can carry SARS

has led some residents in Beijing
to abandon their cherished animals.

Taxi authorities
have set up points

to test cab drivers for high temperatures,

one of the symptoms of SARS.

In part, it's all down to how much
we, the public,

trust what we're told by officials.

Is it absolutely out of the question
that this could have been something

inflicted upon people
by a terrorist agent of some sort?

I think in March of the year 2003,
we exclude nothing.

1755 people were infected
in Hong Kong and 300 died.

In Toronto,
251 were infected and 41 died.

With cases
in at least 26 other countries...

ultimately, SARS killed 774 people,
about 10% of those it infected.

But then SARS did something
totally unexpected...

The funny thing about SARS is that
after a while it just kind of goes away.

SARS just wasn't that hardy a virus.

We didn't know that when it started,
but that's how it turned out.

But I don't think that's a success story.

I think a lot of that is just luck.

Because a lot of mistakes were made.

Chinese health officials only admitted
there was an outbreak

after 18 people had already died,
and hundreds of others were sick.

We will try all means to
reverse and improve upon the weaknesses

and faulty aspects of our work.

After the SARS epidemic,
the World Health Organization

brought together 196 countries,
and they all committed to improving

their ability to "detect, assess, notify,
and report public health events,"

including outbreaks.

In 2014, only a third of them
were in compliance.

The big problem with the pandemic
is we don't know when it will come.

And so it's very easy to put off
to another day.

It really takes an extraordinary act
of political will to say,

"Yes, right now things
don't look that bad,

but we're going to send funding
to public health anyway

because we know that someday
it will be bad."

SARS showed how far and fast
a virus can travel in our modern world.

SARS went around the world in weeks.

It's entirely possible that the next
will go around the world in days.

That's far faster
than we could ever catch up.

Which means,
if we want to stop the next pandemic,

our best bet is catching it at the source.

SARS began as a virus living silently
in a wild animal.

Experts believe it was bats
here in southern China.

These scientists have been coming
to these caves since the outbreak,

catching bats and scanning them
for viruses similar to SARS.

And they're finding a lot,

which is allowing them
to create an early warning system.

And when we find them we raise the alert,
and the government of China comes in

and tries to reduce the exposure
of those populations to viruses.

China is not the only place
these viruses are being found.

This map shows where a new virus
is most likely to emerge.

The front line for disease emergence
are places like the end of the road

in a tropical forest
where someone's just built

a new mining concession.
People have moved in.

There's no food supplies so they go out
and hunt wildlife.

Or it's a farm in Southeast Asia
that's been expanding and intensifying

that has bats nearby that spread viruses
into the pigs in the farm.

This is a revolutionary way to defend
ourselves against future pandemics,

but it won't catch every new disease.

For that, we need to improve our vaccines.

If a disease comes along
that we haven't seen before,

typically it would take four or five years

to come up with a vaccine
against that disease.

And new technologies
might shorten those times.

That's why an organization
called CEPI was founded.

And they're developing a vaccine
for Disease X.

Traditional vaccines inject
protein molecules from a virus,

and manufacturing these proteins
is a long and expensive process.

But this new vaccine doesn't use proteins.

It injects genetic material that tells
the body to produce those proteins itself.

Your body becomes the manufacturer,
creating the protein molecules

and then the antibodies for them.

Scientists can customize
the genetic material to get the body

to produce the protein molecules
of almost any virus.

Once they figure out
how to deliver this into the body,

it could reduce the time
it takes to develop a new vaccine

from several years... to just 16 weeks.

Meanwhile, scientists are trying
to develop a universal influenza vaccine,

one shot that could immunize us
from every possible flu strain for life.

None of those universal flu vaccines,
as they're called,

are anywhere near
to being deployed in the population yet,

but the U.S. federal government
and governments in Europe

have been supporting that research
in a way that they didn't

a couple of decades before,
because they understand

that flu really is an eternal
and very serious threat.

The truth is human technology
has made the next pandemic inevitable.

Deforestation is bringing

more wild animals
into contact with more people.

And factory farming
is pushing animals closer together,

giving their viruses more opportunities
to combine into one that could infect us.

Then we give them
more ways than ever to spread.

But human technology
has stopped pandemics before,

and it's our only chance
against the next one.

We know that, because we've been
in this race since life on Earth began.

When a pandemic comes along, of any size,

we always look back and wish
we'd invested more.

We are far short
of what needs to be done.