Original subtitles

Once again, a scary new virus

is commanding the world's attention.

Information changes daily.

But we know that the Wuhan coronavirus

started in a Chinese hub of 11 million people.

Three million more than New York City.

Wuhan is a city with daily flights

to other countries around the world.

With over 2,000 deaths reported,

and cases of sickness on the rise,

China has put Wuhan on lockdown.

Worldwide, flights to and from China have been canceled.

Ships have been quarantined.

And health officials caution that

an effective vaccine may be a year away.

There are several steps before we can

imagine any mass vaccination program at this stage.

And it's not clear when we will have it available.

The National Institute of Health

is working diligently to develop

a vaccine for the novel coronavirus

by using its own genetic material, or RNA.

What a mRNA vaccine is, is we're essentially

delivering the genetic material,

so we're delivering the messenger RNA

that encodes our mutated novel coronavirus spike.

The messenger RNA will tell the body to present

this spike protein, and the body will respond

by creating an immune response.

But a lot more needs to be known

about this coronavirus before any vaccine

can be effective and widely available.

Just what is COVID-19?

And how does it spread?

Every day that goes by and there are more cases

it's more likely that the epidemic

will surface in other places.

(disturbing music)

Millions of people who will have traveled

across China and around the world

are potentially carrying a virus which is

extremely contagious and proving difficult to contain.

Should we be worried?

What are your chances of getting the latest coronavirus?

One of the things we have seen,

we meaning scientists and epidemiologists

have seen in the last 50 years or so

is apparently an increasing occurrence

of what we call emerging infectious diseases.

Brand new diseases that come out of nowhere,

like AIDS, SARS, Zika.

Or old diseases that we have gotten used to

that we think aren't that big a problem

and suddenly they come roaring back with a vengeance.

So the question is, why is that?

Chinese scientists who identified the virus

named it novel coronavirus of 2019.

It began infecting humans late last year.

But it seems to have originated

in a live animal market in Wuhan, China.

The Wuhan virus belongs to the coronavirus family,

which is a notorious group.

Coronaviruses are an extremely common cause of colds

and other upper respiratory infections.

And they're often zoonosis,

this means they can spread from one animal to another.

Coronaviruses are behind SARS and MERS.

What we know is that this virus

is in the same family of viruses like SARS.

So it is akin and about 80% genetically similar

to the SARS virus.

Some of them originate in animals

and then show up in people.

Based on some of the transmission data from China

not only did the virus jump from

an animal reservoir into humans,

but there is sustained human to human transmission.

Coronaviruses were first

identified in the 1960s.

And get their name from their crown-like shape.

These are the first detailed images

of the Wuhan virus from a US laboratory.

They're similar in shape and size to other coronaviruses,

which have been around for some time.

And how long they go back is a debate.

There is a new belief now that at least

some viruses used to be bacteria,

which are living organisms.

And then learned how to do without

their replication machinery.

Viruses use their host to supply

the structure and energy to reproduce.

Once a virus is embedded its only goal

is to make more of itself.

In humans this typically happens through airborne

droplets of fluid produced by infected individuals,

each drop containing the virus.

Wuhan virus droplets fall to the ground

within a few feet, that makes this virus

harder to get than measles, chicken pox, and tuberculosis,

which can travel a hundred feet through the air.

But it's easier to catch than HIV or hepatitis,

which spread only through direct contact

with the bodily fluids of an infected person.

Coronaviruses use a deadly strategy,

often people are carriers before they

even know that they're ill.

When symptoms arise they vary from mild to severe.

They may include a cough, possibly a fever,

and shortness of breath.

Many people recover within a few days.

But some, especially the very young, elderly,

or people who have a weakened immune system,

may develop a bronchitis or pneumonia.

So far it seems to take two days to two weeks

for a victim to show Wuhan symptoms,

during which time they're contagious.

Stealth is one word that often comes in

because a virus is able to find a cell,

find a host, it's able to get in,

and it's able to crosswire, disconnect,

some of the alarm systems that a body has.

So that it can get a headstart in terms of

replicating itself and moving itself forward

in terms of making enough copies of itself

so it can spread to the next host.

Whenever a new virus appears

health authorities try to predict

an accurate contagion rate.

And to prevent what is known as a pandemic.

Epidemic is when you have a major epidemic

like this one, in one country,

with sustained human to human transmission.

To become a pandemic you have to get

the same situation that we have in China

in more than one country,

and possibly more than one continent.

That is what define a pandemic,

it becomes a global spreading event.

The expectation really at this stage

would be that there should be ongoing transmission.

We need to do everything we can

to try and slow that down.

Viruses are one of the simplest organisms

and one of the oldest organisms on the planet.

Our ability to study them has increased exponentially

over just the past 10 or 15 years, even.

Right now, within 48 hours,

we can sequence the entire genome of a virus,

identify each of the proteins that are present in there,

compare it to all the other viruses that we know of,

find its nearest relatives.

Infer from that how the virus

is probably spreading in the population.

Come up with tests that can then go out there

and test individuals for not only the presence

of an active virus infection,

but we can also then design tests that can tell you

if you have been infected at some point in time

in your life with the virus.

They also try to calculate

how rapidly a virus may spread

by using a reproductive number known as an R0.

The R0 represents how many people

one infected individual may transmit the virus to.

Multiple teams have published estimates

about the Wuhan virus that range from

1.4 to 5.5, making it difficult

to get a clear picture of how contagious it really is.

The World Health Organization suggests

an average R0 between 1.4 and 2.5.

That would make the Wuhan less contagious than SARS,

which had an average R0 of three

and infected more than 8,000 people, 774 of whom died.

The R0 rate for measles ranges from 12 to 18.

But much is still unknown about the Wuhan coronavirus.

If the disease will spread globally,

inevitable it will really affect all areas of the world.

Experts don't yet know

how dangerous this new virus might be

because coronaviruses mutate while they replicate,

evolving and changing quickly.

Well the more you know about the virus

the more you can use natural science, epidemiology,

and all the tools that science provide us

to optimize what we do.

Viruses are very small entities.

They're minuscule.

Millions of them could fit on the head of a pin.

They're very tiny.

And they have very limited nucleic acid.

They're programmed, if you will,

to purposely make all sorts of genetic mistakes

when they are replicated by a cell.

And the reason that's advantageous

is because the one thing a virus can do well

is mutate at a very high rate.

And what that means is if you can mutate at a very high rate

you can potentially take advantage

of not just one but hundreds, thousands,

maybe even more, ecologic niches that you might encounter.

So viruses are sort of the ultimate genetic adapters.

Some of them are uniquely adapted

to thrive in humans, even if they originated elsewhere.

We know that when a virus or a pathogen

enters a new host things will evolve.

What we don't know is where that evolution leads.

Will it lead to increased disease,

will it lead to less disease,

will it lead to increased amounts

of the virus with fewer symptoms?

These are all the potential possibilities,

and it's another reason why

we really need to monitor this infection

and these outbreaks very very closely.

Not only from the aspect of preventing disease

in the public, but also because we want to

keep track of how the virus is changing

and make sure that we're trying to keep up with that virus

in terms of how its properties might be changing

now that it's seen so many individuals.

Scientists studying the SARS virus in 2005

discovered that it was originally present in bats.

And that somehow made the leap to infect humans.

One category is newly emerging.

A brand new virus that wasn't affecting people before.

It might not even have been noticed in animals before.

That was true of SARS, for example.

And despite the Wuhan virus' sudden infamy,

it's been around for a while.

Something very similar was found several years ago

in a cave in a province roughly

a thousand miles southwest of Wuhan.

A field team took blood samples

from a couple of thousand people,

about 400 of whom lived near the cave.

Roughly 3% of them carried antibodies

against SARS related coronaviruses, like the Wuhan variety.

They weren't able to determine if the carriers

had actually gotten sick, or if they'd been exposed.

In these fearful times,

Beijing's hospitals look like battlegrounds.

A sick man is carried into one of the places

where checks for SARS are now being done.

But they knew that the SARS virus

had made the jump from bats to humans.

So they believed that the new coronavirus

also emerged from an animal, probably a bat.

Then it may have passed through a second

intermediate host, like a pangolin,

before appearing in humans.

It's what viruses do best.

What infectious diseases wanna do

is spread to the next host.

The common flu, or influenza,

is a virus, but it rarely gets the attention

of things with exotic names.

For most of us the flu is old news,

whether or not we get our yearly shot.

Viruses named after foreign places,

like Ebola, Zika, and Wuhan, inspire terror.

It's still tough to assess how lethal

the Wuhan virus may be.

The worst cases are usually detected first.

And so far, about 2% of these have been fatal.

But people with mild cases may never visit a doctor.

There may be more cases than we know,

and the death rate may be lower than initially thought.

There is one key element here, that is,

are people infected with the disease

able to transmit the disease

before developing symptoms or not?

Depending on what is the fraction of pre-symptomatic

transmission the disease will have a different pace.

Because while we can isolate people with symptoms

we can decrease the transmissibility

of the disease that way.

If a large fraction of the transmissibility

is during a pre-symptomatic phase

it's impossible to isolate people.

And so the disease will move more rapidly across the world.

Worldwide we're already

dealing with a dangerous epidemic.

According to the CDC, influenza has already sickened

at least 15 million Americans this season.

Hospitalizing 140,000, and killing 8,200.

In a bad year the flu kills up to 61,000 Americans,

and worldwide more than 650,000.

While health workers and scientists

are still learning about the Wuhan virus

perhaps the biggest concern is that,

in milder cases it can masquerade as the flu.

And that makes distinguishing between the two

more difficult and increases the chances of transmission.

When it comes to the Wuhan coronavirus or any new virus,

increasing global connectivity magnifies the problem.

We have to be aware that now every place in the world

is one flight away from China.

And every place in the world

is one flight away from almost all other places.

It might be two flights instead of one,

but we are living in a global interconnected world.

But the experts are on the case.

Today we can do all these things in a matter of hours.

And we can come up with tests that tell you

if you're infected, we can come up with tests

that tell you if you have been infected previously,

and controlled the infection.

And we can do so in a matter of days

what used to take years to do,

in the 50s, and even in the 80s.

So our technology has progressed significantly

in terms of our ability to do things

effectively and quickly.

It really is now our ability to implement

all these things that is something that

our public health officials are working on.

Thwarting this virus, or any new disease,

requires a hands-on approach by multiple partners.

Since the very beginning, all the agencies

have had a good deal of coordination.

The World Health Organization, Center for Disease Control,

European Center for Disease Control.

And they have created a network of people they talk to.

For now, health officials say,

the best precaution is the simplest, wash your hands.

(disturbing music)