Each bar shows how many new infectious diseases

emerged in a year.

In 1944, there was one.

In '48, three.

We have no immunity to new pathogens.

Each disease on this list posed a new pandemic threat.

It was around 1960 when the number began to rise.

By the time 1990 rolled around,

it wasn't just two or three new diseases that year —

there were 18.

Soon after, the trend became so clear,

a scientist appeared on TV with a warning.

“What worries me the most is that we're

going to miss the next emerging disease,

that we're going to suddenly find a SARS virus that

moves from one part of the planet to another,

wiping out people as it moves along.”

That was 17 years ago.

And today, stuck at home in a seemingly never-ending

pandemic purgatory, it appears that we did not

heed his warning.

Covid-19 has opened our eyes to the danger.

But has it opened them enough to look past this pandemic

to what our future holds?

We tracked down that same scientist today

to ask him: How do you stop the next pandemic?

He said the trend isn't looking good.

“We see an increased frequency of emerging pandemics.

We also still have the ones that emerged recently.

We still have H.I.V.

We still have Ebola.

We still have H1N1.

So we're adding to the stock of known pandemic pathogens

with new ones at an increasing rate.

That's not a good place for us as a species right now.”

If you want to know how to stop the next pandemic,

you first need to know why they're happening.

“We humans are an ecological anomaly.

There have never been 7.7 billion large-body

vertebrates of one species on this planet

before in the history of earth.”

This is David Quammen.

He's a —

“— a very unmystical, black-hole Darwinian materialist.”

Well, David's a storyteller.

He's been writing about the origin of infectious diseases

for decades.

“So we are unprecedented, and we're

causing ecological wreckage that's unprecedented,

and there are consequences of that.”

[explosions]

“Pandemics emerge due to our ecological footprint.

And our cultural footprint is accelerating exponentially.”

Remember this guy?

That's Peter Daszak, the scientist who warned us in 2003.

He's sometimes referred to as a virus hunter.

He goes out to preemptively find viruses

before they find us.

“It's the connection between humans and animals

that's driving this.

And that connection happens where

people move into a new region through things

like road building and deforestation, mining,

palm oil production, timber and livestock production.

People move into new areas.

They come across wildlife that we've not really

had much contact with.

The pathogens spill over into them, and then

can spread through that connectivity.”

[birds squawking]

“We're encroaching on their habitats.

And just many, many more opportunities for spillover

events to occur.”

Christian Walzer is a global veterinarian

and executive director for the Wildlife Conservation Society.

“The destruction happening at the edge of forests

is one of the areas where we're very concerned.

Changing the trees that bats, for example, would roost on,

they may be driven to an edge.

They may be driven into an area where there's

more human population.

And suddenly, you create a contact area

which didn't exist before.”

So what do these new contact areas look like?

In this video, we're going to show you

three ways in which our changing

relationship with wildlife is increasingly

creating dangerous pandemic possibilities.

So let's say you want to sell toothpaste.

No, peanut butter.

Wait, wait shampoo.

Never mind, it doesn't matter.

In all of those cases, you need palm oil.

So you burn down a forest in Malaysia to grow palm trees.

But that forest was home to some bats.

So the bats find a new home, near some fruit trees

on a pig farm.

But soon, a virus from those bats

makes its way into the farmers who own the property.

This isn't science fiction.

This is how the Nipah virus came to humans.

“Why was it getting from the fruit bats to the people?

Because of habitat destruction.

Most of the forest in northern Malaysia,

where the bats would ordinarily

be living wild and feeding on wild fruit, most

of that forest had been destroyed.

In place of the forest, among other human enterprises,

were giant pig farms, piggeries,

where thousands of pigs were kept in a single corral,

being raised for meat.

Some of those corrals were shaded by domestic fruit

trees that were planted to grow mangoes

or to grow starfruit for another revenue

stream for these pig farms.

So the bats, having lost their wild habitat,

are attracted to the domestic fruit trees.

They come in, they eat the mango,

they eat the starfruit, they drop the pulp

into the pig corrals.

And with it, they drop their feces and their urine

and their virus.

It gets into the pigs, spreads through the pigs,

then gets in the pig farmers, pork sellers,

and other people.”

Land use change is one big reason

more infectious diseases are making their way into humans.

However, it's not just animal habitat

we need to worry about.

Animal diversity can be just as important.

“Loss of biodiversity itself has

led to emergence of disease.

When you lose species, you tend

to be left with certain groups.

And if they happen to carry viruses,

and if they dominate the landscape,

you will be exposed to those viruses more than others.”

This story doesn't begin in the jungles of Africa

or forests of Southeast Asia.

We begin in the American suburbs.

“If humans cut down the forest and turn it into a suburb,

like those beautiful suburbs we

know in semi-rural Connecticut,

where there are great big lawns in front

of nice houses, and there are hedges,

and then there's somebody else's house

with a great big lawn in front of it,

that's really good habitat for white-footed mice,

and also for white-tailed deer.

Not so good for larger mammals,

like foxes, like weasels, or for birds of prey.

So the hawks and the owls tend to disappear,

the foxes and the weasels tend to disappear

from this environment.

What happens then?

You get more white-footed mice.

You get an abundance of white-footed mice

because their predators are not suppressing them.”

Having an abundance of white-footed mice

wouldn't be so bad, except they

are the natural reservoir host of Lyme disease.

This means they harbor the bacteria,

but it doesn't make them sick.

So if there was a biological diverse landscape, well,

then —

“The pathogen is shared amongst the various hosts

that are in that landscape.

Many of these hosts are incompetent

and are unable to actually transmit the disease.

And so it becomes a dilution effect.”

“The net result of this reduction

in biological diversity, changing the landscape,

making it more fragmented, less forested,

is more ticks infecting more little kids

when they go out to roll around in the grass and bust

through the hedges.

So there is more Lyme disease.”

And yet, Covid-19 may not have started this way at all.

“In view of the ongoing outbreak,

if you create a completely artificial interface where

you go and capture animals regionally, globally,

and bring them together at one place,

like at a wildlife trading market,

then you're obviously creating fantastic opportunities

for viruses to spill over.”

A pathogen from an animal might not

be able to spill over directly into humans,

but it could spill over into another animal,

evolve or adapt, and then infect humans.

With a rotating variety of animals stacked

on top of each other, the pandemic possibilities

are significant.

This is one theory of how the coronavirus may

have started in China.

The thing is, in the past, a spillover event from this

wildlife market may not have affected you.

“We also have to take one step back from the sort of very

romantic idea that these are isolated communities living

in central Africa.

You know, I always point out that a rat which you capture

somewhere in northern Congo now, within 12 hours,

you're in Brazzaville.”

“The Republic of the Congo now has a new modern highway

and economic artery thanks to Chinese assistance.”

See, just 10 years ago, that would have been impossible.

But then, well, China —

“The national highway was complete —”

China wanted access to minerals to mine.

In exchange, they helped with infrastructure.

Now, there's a road.

They've created accessways, not only

for the rare earths which are so

important for your mobile phone,

but for viruses as well.

“If you catch the plane that evening

and you take your rat with you because you want to bring it

to your family in Paris, it's less than 24 hours

from a very, very remote community

all the way to Paris.”

But luggage is screened, you say.

The rat would get caught.

Maybe.

But really, the rat isn't the biggest threat.

It's you.

Your bag gets screened.

Your blood does not.

“We all have a share of the responsibility.

It's not just people in China who want to eat bats

or who want to eat pangolins.

That may be the immediate cause of this spillover,

but in terms of the initiation of these things,

generally, there is also enough blame, enough responsibility

to go around.”

The three ways in which a pandemic

could start shown in this video all

have one thing in common —

us.

“Here's what we did.

We changed the planet so significantly and so

fundamentally that we dominate every ecosystem on earth,

right now.

We are the dominant vertebrate species.

Our livestock are the dominant biomass on the planet.

And that's the issue.

What we've done is we've created this pathway

through our consumption habits by which

viruses can get from wildlife into people

and then infect us.

And our response is we blame one country versus another,

we blame people who eat one species over people

who don't eat another and we blame nature.

Well, no.

We need to point the finger directly at ourselves.

This is not a whiny argument that the world's falling

apart and it's our fault, this is

an argument that says we are the reason why this happens.