All language subtitles for NOVA.S47E07.Decoding.COVID-19.1080p.AMZN.WEB-DL.DDP.2.0.H.264-GNOME_track3_[eng]

A world turned upside down...

We are in a dire situation.

With deserted streets

and hospitals filled
to the breaking point.

Everyone is at their limit.

Chaos caused by
the tiniest of enemies,

thousands of times
smaller than a grain of sand.

We've seen pathogens
emerge all over the world.

We just don't really know
what we're dealing with.

This is much more contagious.

And it's changed how
we practice medicine.

If the majority of the
population gets infected,

there will be
enormous loss of life.

How can we stop
this invisible killer

that is baffling scientists?

There are people
who get this infection

shedding the virus
before they get sick,

and may never have any symptoms.

A global race to find
treatments for the sick

and a vaccine to
protect the healthy.

This ends with most or all of
us being immune to this virus,

and ideally, that's
through a vaccine.

Can solutions that
usually take years...

We are trying to move
as fast as we possibly can.

Be found in a matter of months?

It is an extremely
revolutionary approach.

To get into a
phase-one clinical trial

66 days after the sequence
of a virus is released

is a world record.

Will we face more
waves of infection

before science can
defeat the coronavirus?

Time is the one thing

we don't have right now.

"Decoding COVID-19"...

right now on "NOVA."

Wuhan, China.

December 31, 2019.

Reports of an outbreak
of a mysterious illness.

Symptoms include
a fever, a dry cough,

and in some cases,

severely compromised breathing.

The international
press picks up the story.

Scientists in China
are trying to determine

if a new virus
strain is responsible

for a pneumonia outbreak
in the city of Wuhan.

For the moment, it
seems a world away.

As of now, there has not
been a U.S. infection, as of yet.

But for some scientists, this is
exactly the early warning signal

they've long been dreading.

The future of the
people of China,

and not only of
Asia, but of the world,

could be at stake here.

I think all of us
held our breath.

Because the question was,

could this be that
combination of a virus

that's both easy to transmit

and perhaps maybe not as deadly
as what we might see with Ebola,

but still have just
devastating impact

on the resilience
of our communities?

The initial fear is
that some kind of virus

might have jumped from
an animal to a human

and then spread.

It's happened before.

One possible way
transmission can occur

is in markets where
domesticated and wild animals

are kept in close proximity,

common throughout Asia.

And you can see hundreds
and hundreds of different animals

of every imaginable creation...

from many different locations

that are sold as food.

Wet markets were a major
suspect in the deadly SARS outbreak

that began in 2002.

It spread to nearly
30 countries,

infected over 8,000 people,

and killed 774 before
it was contained.

But some scientists believed

the world had actually
dodged a bullet.

That a future epidemic
could be much, much worse.

And in January,

there are signs that that
future may have arrived.

Because this virus appears
to be more contagious

and stealthier.

As alarm over the virus grows,

researchers
scramble to analyze it.

Then, on January 10,
a major breakthrough:

Chinese scientists
publish the entire genome

of the mysterious pathogen.

Rhiju Das, and
scientists worldwide,

begin to decipher
a genetic sequence

that's never been seen before.

The virus actually has probably
been out there in the world

and evolving for,
probably for a while.

Probably in bats, actually,

and then maybe through
an intermediate animal

that we don't yet really know,

it's now jumped into humans.

So it's not a novel
entity on Earth,

but it is novel in humans.

It may be novel to us,

but it belongs to a
family of pathogens

called coronaviruses,

named for the spikes that
protrude from their surfaces,

giving them a
crown-like appearance.

Coronaviruses are little more

than a set of
genetic instructions

wrapped in a fatty
shell with protein spikes.

These spikes are like keys,
which lock into receptors

on cells in your
lungs and elsewhere.

Once the virus enters,
its cargo of genetic code

takes over the cell's machinery
and makes new viruses,

which head off to
infect more cells.

At the National
Institutes of Health,

immunologist Kizzmekia
Corbett studies these pathogens.

Coronaviruses,
there are hundreds.

We've heard about MERS
and we've heard about SARS.

There are four
additional viruses

that circulate in humans

and cause some level of cold
and sniffles and throat aches

in people every single year.

Scientists estimate there
are more viruses in the world

than stars in the universe.

Luckily, most are harmless,

whether they're
around us or in us.

And many have left
their mark in our DNA.

When the human
genome was sequenced

at the end of the last century,

I think one of the big surprises

was that our genomes are
full of the fragments of viruses.

And they're basically
the remnants

of all of these relatively
harmless viral infections

that we're constantly
undergoing.

The danger can come

when we run into a
virus we've never met.

When a virus jumps
from another animal

and finds a way
to infect a human,

they typically have not evolved
to be a nice partner to us.

They will replicate like crazy.

It's very difficult on a cell
to be infected with the virus,

because the virus sort of says,

"Stop doing what
you're programmed to do.

Instead, do what I
program you to do."

Our human bodies haven't had
enough time to evolve defenses

to make sure
everything's under control.

And those are the viruses
we have to worry about.

In China, word of
the virus is traveling.

I heard about an
unknown pneumonia

spreading in Wuhan

in early January.

Liu Qi is a 21-year-old
university student in Wuhan.

The news had been
saying it's not a big deal.

I went on with my life.

But then, on January 17,

Liu comes down with what
he thinks is just a seasonal bug.

I thought it was a regular cold.

Four days later,
he develops a fever.

I called my dad, told
him my symptoms.

He thought it was weird and
asked me to return home A.S.A.P.

We went to the hospital
for a check-up that night.

A scan showed my
lungs were infected.

The doctor gives
him a prescription

and tells him to stay
at home and rest.

Until then, he hasn't
been terribly anxious,

but that changes.

As soon as I started
taking the medication,

my symptoms got worse.

I lost my appetite,

I couldn't keep anything down,

and I had terrible diarrhea.

I felt really bad.

Liu's fever is a sign

that his body is under
siege from a foreign invader

and starting to fight back
with its only available weapon:

his immune system.

It's like a thriller.

There are bad guys and then
there are good guys, okay?

And the bad guys are viruses
and bacteria and foreign junk

that is always coming,
intruding in our body.

The "good guys" are billions
of immune cells and proteins

that are constantly
on the lookout.

They will essentially
act like a police force,

where they see the invader,
this virus that's coming

to set up shop,
essentially, in your lungs,

in your nose, in your throat.

The immune system
begins to sense

that there is a foreign
invader inside the body.

They go back to headquarters,
which is in our lymph nodes,

and they say, "We got to
go and figure out a response."

And what those cells do is,

they can start to educate
the immune system

of what exactly this
pathogen looks like.

While this battle rages,
Liu's symptoms worsen.

I start to worry that I
caught the disease.

I never felt so much pain.

I felt like I was dying.

I was scared.

A second scan
reveals an infection

from the COVID-19 virus

is spreading
throughout his lungs.

Meanwhile, it's spreading
throughout the world, as well.

After surfacing in Wuhan,

the virus rapidly
crosses borders,

reaching Thailand,
Japan, South Korea...

and beyond.

When we saw this outbreak,

we were struck by the rapidity

with which it spread
geographically within China

and how it quickly translocated

to other countries
around the world.

Hotspots soon erupt in
the Middle East and Europe,

with Italy hit hardest.

It was really like
tracking a race.

And so what that told us

is that even before
symptoms began to manifest,

that's when individuals
could be highly contagious.

Within months, the virus
reaches every continent

except Antarctica,

including North America.

There are a lot of people

who are unaware
that they're infected.

They never become symptomatic,

or if they do, they're
mildly symptomatic.

They don't stay home.

They ride public
transportation, they go to work,

they get on airplanes
to take business trips.

They take the
virus to new places

and introduce it to
new communities,

where it then spreads further.

Coronavirus cases in the
tri-state continue to rise.

This morning, there
are 44 confirmed cases

of the disease...

In late February,
the virus still seems

like a distant threat
to many New Yorkers,

like Jessica Brown,
who lives in Queens

with her husband,
three children,

and her father, George.

At age 73, keeping up with
his three active grandchildren

is not a problem.

My grandfather's personality
was "one of the kids."

He was the first one to come up

with doing something
goofy or silly.

He was at every sporting event.

He was at every graduation,

every spelling
bee, every birthday.

Dad never knew what the
adventure was going to be.

But he never said no.

He always just said, "There
I am, kidnapped again."

The first week of March,
George makes it to four

of his granddaughter's
basketball games

and a Broadway play,

unaware that the
coronavirus is all around him

and could be contracted
with astonishing ease.

Studies reveal it can remain
infectious on some surfaces

for up to three days,

or suspended in the
air for a short time

after an infected person
coughs or breathes.

When my grandfather
first started to get sick,

it was, you know, "I
have a stuffy nose,

but, you know, I'm okay,
I'm hanging in there."

We all just took it as if
it was a common cold.

Over the next three days,

his symptoms rapidly get worse.

I said, "Dad, I think you
have to go to a doctor.

I just don't like
the way you look."

And he said,
"Oh, stop it, stop it.

Let's see what happens
when you get home from work."

Friday, I get home from
work, he was shaking.

My mom called me the next
day and that's when she said,

you know, "Pops
isn't looking good."

You know, "He's
starting to tremble

"and he just seems like he's
moving significantly slower

than he was the day before."

So I brought him
into the hospital.

They didn't think that
it was coronavirus,

but they did take him and
put him in isolation anyway,

'cause this was just
the beginning of it.

They gave my husband and
myself a mask and asked us

to please wait in
the waiting room.

I saw him leave to
go get a chest X-ray.

I said, "How do you
feel?" He looked better.

They gave him some oxygen.

He gave me a thumbs-up, and told
me to bring him some newspapers.

Hours later, George
is taken to the I.C.U.

and diagnosed with COVID-19.

The liaison between the
critical care team and his family

is veteran palliative
care doctor Alice Beal.

This is somewhat reminiscent

of the AIDS crisis, in
the fear that people have.

But this is much more
contagious than AIDS ever was.

And it's changed how
we practice medicine.

We touch, we examine, we listen.

In this pandemic, I don't
even get to see my patients.

I don't even get to
talk to many of them.

That is certainly
true for George,

who, like many
coronavirus patients,

is struggling to breathe.

In healthy lungs, tiny air sacs
deliver oxygen to blood vessels.

But as the virus kills cells,

and the immune
system fights back,

inflammation results, filling
the lungs with fluid and debris,

blocking the flow of oxygen.

What happens to some
of these individuals

that go down this severe path

is, they begin to make

this massive burst of
inflammatory molecules

that we call the cytokine storm.

Now, once that signal or
that alarm goes off in the body,

all kinds of other immune
cells that we have in our system

start to swarm in.

That then basically
sends the immune system

into this incredible disarray.

Your own immune system then
becomes an enemy to your body.

So in that combination
of both the direct damage

that the virus does

and the inflammation that comes

from the immune system
overreacting to the virus,

you get a scenario where people
start to have trouble breathing.

Many patients, like George,

end up needing a
mechanical ventilator

to do their breathing for them.

Throughout the night, he
started showing symptoms,

and they had to
put him on a vent.

And once they said that
they put him on a vent,

I just knew that it wasn't good.

It was such a shock
to his daughter

that when I called her,

she just couldn't understand
how this could happen.

I told her this is what
this disease does.

She said that many
things are going on

in Dad's body right now.

His enzymes are low, and it's
showing that he may be having

a massive heart attack.

She wanted to come in.

She desperately
wanted to come in.

She said, "I won't even
bring my kids, just me."

And I said, "No,
it's just too unsafe."

No families are allowed in
the hospitals at all, anywhere.

15 minutes later,
I called her back,

and I said, "Please,
we need closure."

And she said, "You hold
on, you give me ten minutes

"and gather up your troops,

and we are going to
figure something out."

There are no phones
in the rooms in the I.C.U.

and he didn't have a smartphone.

One of my residents figured out

we could hook the intercom
up to a speaker phone.

It wouldn't be private, but
the family could say goodbye.

My whole family was
together in our kitchen,

and, and our dog Charlie,

and she had us go
on speaker phone

over an intercom into
my grandfather's room.

And all five of us were able
to say our goodbyes to my dad.

Obviously through a
lot of tears and crying.

And that was the
closure that we needed.

He heard us, he
heard us say goodbye.

Seeing these people
going to the hospital alone

and not being able to
bring their loved ones

and have no one there,

I think that
everyone hearing it...

for the healthcare professionals
and for the patients there...

that it would give
a sense of hope.

And yes, you're in the
hospital, you're alone,

but the entire world is thinking
about you and praying for you

to pull through and, you
know, get through this.

After his grandfather's death,
Matthew is called back to work.

As a New York City E.M.T.,
he is desperately needed.

When I went back to work,

it seems that we were
smack in the middle of chaos.

And I could look at my
partners' faces and just see

that they're already drained.

And they would just shake their
heads and say, "Matt, it's bad."

We're bringing
people to the hospital

and we're waiting
three-and-a-half hours

to get them into a
bed in the hospital

because there's
nowhere to put them.

So, they're just sitting in
our stretchers declining.

16-hour shifts, answering
call after call, are now the norm,

as is telling patients' families
that nothing can be done.

Just shocked at how many
are... I'm actually seeing deaths.

We just came out
of one pronounced.

We're coming
across these patients

who have been
tested for the virus,

and they tested positive,
and they're sent home.

We're getting called
into people's homes,

and they're in cardiac arrest.

And they're not breathing,
they have no pulse.

And, you know, we're
asking what happened,

as we begin doing CPR.

It's almost too late.

We can't help anybody.

Everyone is at their limit.

And all we can think about
is when it's going to end.

Across the city, Jeffrey Shaman
is asking the same question.

Using data collected
by the "New York Times"

and the U.S. Census Bureau,

he models how the
outbreak might evolve

under different
control measures.

In one scenario, if the virus
is allowed to spread freely,

infection rates would soar,

overwhelming the
healthcare system.

We get a trajectory that shows
a very aggressive outbreak,

where roughly 75% or
greater of the population

is ultimately
infected by this virus

by the end of the summer.

And if regions adopt only
partial control measures,

the results would
hardly be better.

Only strict social distancing
imposed nationwide

would slow the
rate of infection.

The spread of
this virus is no joke,

and it is crucial for
people to stay home.

Speaking about
how the virus spreads

and how people
could be carrying it

and infecting others
without even knowing it

really touches
close to home for me.

Because I was sick
before my grandfather.

And how do I know that
that wasn't the virus in me?

And I was hanging out
with him while I was sick.

We went for walks,
we went to get coffee.

And what if I'm a carrier
and I gave it to him?

But strict social distancing

comes with its own
tremendous toll...

economic paralysis,
mass unemployment.

And that's the thing that
makes people really anxious.

And I totally get that,
because on one hand,

we don't want
people to die here.

On the other side, unemployment
rates are skyrocketing.

People don't necessarily
have food security.

And the economic
consequences of doing this

over maybe even a year or longer

could be utterly devastating
and hard to pull out of.

There are 320 million
Americans today.

We have every reason to believe

that over the next
16 to 18 months,

at least half of them
will become infected.

So, 160 million people.

This virus will find people
who are susceptible.

Therefore, as soon as we
have the least bit of let-up

for any kind of these
intensive control measures,

the virus is going to come back.

So is there a way to
safely restart our economy?

Perhaps, if we
embrace strategies

that stop transmission...

isolating the infected,

instead of shutting
down an entire country.

It's case-finding, it's
finding people who are sick,

and it's contact-tracing...

looking at everybody
else the person who is sick

has been in contact with.

Then bringing everybody
who we know is sick to care

so they do not continue
to transmit that infection

in the community.

Can you pump
your hand a little bit?

But is there another
possible solution...

All right, a little pin prick.

Using blood tests

to determine who may
already have immunity?

Oh, you're good.

To find out, Duane Wesemann
is biking samples of blood plasma

across Boston,

to the lab of Galit Alter.

Hey. Hey, Galit.

Hey, Duane, thanks
for bringing them over.

How many do you have today?

Okay, we have about 40.

Okay, that's a
good batch, thanks.

Alter is testing the
plasma for antibodies...

proteins in the immune system
that find and destroy invaders.

Antibodies are molecules
that can see the target

absolutely specifically.

And those antibodies
start to stick to the pathogen

and to the infected cells

and start to direct
the immune system

to kill those particular
targets as rapidly as possible.

And so these antibodies
constantly mutate

and they constantly evolve
in order to bind tighter

and more specifically
to the virus.

How's it going over here?

For Alter's test
to be effective,

it has to be able
to tell the difference

between antibodies
to the COVID-19 virus

and other coronaviruses,

like those that cause
some common colds.

So this is the common cold,

and this is the
novel coronavirus.

This looks good.

We just don't want any,
like, false positive detections.

A single plate contains
the plasma samples

from 175 patients.

So what our tests do is, they
essentially allow us to detect

exactly how much
antibody is there

through particular
reagents that change colors.

If COVID-19
antibodies are present,

coloring agents will turn the
plasma blue, and then yellow.

Everything that's
yellow will be positive,

and of course, there's
different levels of positivity.

Depending on the
intensity of the color

that appears inside the well,

we can actually tell the
exact amount of antibody

you have in your immune system.

And it gives each well a number.

The higher the number, the
more antibodies this person had.

Most commercial tests are
only giving us a yes or no answer,

you do or don't have antibodies.

What our particular
antibody test does is, it tells us

exactly the level of antibody
you have in your blood,

Because we believe
that this level is really

what is going to dictate
whether or not you are going to be

protected from infection or not.

Even if you have the
right level of antibodies,

are they the right type
to neutralize the virus?

If so, how long will
they protect you?

Are they like
measles antibodies,

which may confer
lifelong immunity?

Or seasonal flu antibodies
that shield for less than a year?

Can you put the last guy
here? Where's the last guy?

To find out, Alter's lab is
working with Boston hospitals

to follow patients with
COVID-19 antibodies

for the next two years.

The people who are
testing positive do have

very high levels of antibodies.

She will check their
antibody levels periodically

and keep track of
who gets reinfected.

There is this idea that if you
have a positive antibody test

that this may be sufficient
for you to return to work

and reenter society.

But what we've learned from
many pathogens over the years

is that it's not
black and white.

And what this type of
analysis allows us to do now

for the first time

is to define the
specific characteristics

of an antibody

and the absolute level
of antibody that gives you

complete protection
from disease.

Once we have that number,

we have the ability to
give out those passports

that will allow people to
reenter the population safely.

While scientists
work around the clock

to find ways to
understand the link

between antibodies and immunity,

some doctors resort
to an old practice...

borrowing immunity
from recovered patients.

One of the oldest
therapies that we have

in medical practices

is the transfer of immune
plasma to people who are sick.

And that's really what opened up

this entire field of
antibody therapy.

In Wuhan, after a
torturous three weeks,

Liu has tested
negative for the virus.

Today, he's making
another trip to the hospital.

But not because he's sick.

Doctors hope that Liu, as well
as other recovered patients,

have immunity.

The antibodies that his body
manufactured to fight the virus

are still coursing
through his blood.

The virus is still
a threat to others,

so Liu offers to
donate blood plasma.

But it's not easy.

Drivers are wary
of being exposed.

Liu does his best
to be reassuring.

I saw so much tragedy
during this pandemic.

My motivation
is to help doctors,

help them save more people.

I wish I could
have been a doctor.

So, as a normal person,

I feel that donating blood
is what I can do now.

Inside, staff wear
ample protective gear.

He's checked for
fever, examined,

and asked about
his general health.

During the donation, your
blood flows into a machine

that separates the plasma

from red blood
cells and platelets.

Those come back into your body

while the hospital
keeps the plasma,

which has antibodies in it.

As he leaves, staff give
him a can of protein powder

to help keep up his strength,

along with thanks
and a certificate

marking his contribution.

Plasma like Liu's is being
used as an experimental therapy

for severely ill patients.

At this point, doctors are
desperate for treatments

that will help.

Emerging infectious
diseases are challenging

because we're learning about
both the virus and the disease

as we're responding to it.

New evidence is coming out
about how this virus is transmitted,

where the virus lives
in the human body.

And so we are at a place where
we're making medical decisions

on the go as science changes.

With reports of COVID-19

ravaging hearts,
livers, and kidneys,

and causing blood
clots and strokes,

the health risks
seem worse than ever.

Although severe illness is less
common for people under 65,

no one can know for sure how
the virus might impact them.

We're seeing patients of
every age walk through the door.

It is a misnomer to say that
the young are immune to this.

We constantly see people
who are in their 20s, 30s, 40s,

you know, and some who do
not have any medical conditions,

because it's a brand-new virus,
and none of us are immune to it.

Since no one is immune,
could there be a treatment

to reduce the severity
of the disease?

That is something Robert
Davey at Boston University

is racing to find out.

Our ultimate goal is to
have the designer molecule

which will specifically
attack the virus

and do nothing to
the rest of your body.

Something that stops
the virus dead in its tracks

and doesn't affect you
in any way whatsoever.

This is a level-four
biosafety lab...

one of only a few in the U.S.

Biosafety level four is
when you're in a bubble,

a suit that looks like what
the Michelin man has on.

It's inflated by air.

So this is the highest
level of protection.

This is probably
the safest place

in the country to be right now.

Any laboratory facility that
studies emerging pathogens

is designed around
safety and security.

The CDC does not
require this level of safety

for the coronavirus.

But it was much more
efficient for this lab

to launch research
at level four,

because before COVID-19,
Davey was studying Ebola.

Now he's testing thousands
of drug compounds

that just might
be the right shape

to disable this
novel coronavirus.

This is what the
process looks like.

So we have the plates with
the 384 little wells in them

and each one
gets cells and drug.

And then we take those
plates to the containment lab

and we add virus
to all the wells.

The concoction of human
cells, virus, and potential drug

is then set aside to see if
the virus will infect the cells

or if the drug will stop it.

Next, Davey
analyzes the results.

We put on a dye onto
the cell so it's colored.

And every time
a cell is infected,

that cell will now glow green.

And you just add them
up... just count up the dots.

Here, cells glow blue.

But if they become
infected, they glow green.

The fewer green cells,
the more effective the drug.

And that's how you know

if the drug is working.

I know people who are extremely
anxious about the pandemic.

And I also feel that anxiety.

I have two daughters
that work in supermarkets.

I worry about them every day.

And I have elderly parents

and I want to make sure
they're still here after this.

I'm trying to as quickly as
possible get to a treatment,

but I've got to be safe
and I've got to be careful

and I've got to
do scientific rigor.

In late April, the N.I.H.
announces that preliminary data

from a study of the
antiviral drug remdesivir

suggests it helps
severely ill patients

recover a few days sooner.

Although the
results are promising,

many believe antiviral drugs
alone won't be enough to save us

from the ravages of COVID-19.

For myself and everyone
else on the front lines,

we fear every day
for our loved ones.

People that I work with
are sleeping in their cars

because they're scared
to go home to their families.

We're really not going food
shopping because we're worried

about giving it to other people.

Thank God for the people
that are donating food

to where I work.

The health care workers
are under a lot of pressure.

They're exhausted, but
they're also retraining

to be in a marathon,

so that we can continue
this for a long time.

So how does this end?

This ends with most or all of
us being immune to this virus,

and ideally, that's
through a vaccine.

It cannot be through all of us
getting sick at the same time.

If you just sort of let it
run wild in your population,

sure, you'll eventually get to
that immunity that you'd like,

but it might take,
unfortunately, a million deaths

for you to be able
to achieve that.

The Holy Grail for
science is now a vaccine.

In January, once the coronavirus
genome was published,

scientists around the
world sprang into action.

I set alerts

on all of my mobile
devices and my computer.

N.I.H. immunologist
Kizzmekia Corbett

is one of an elite
army of scientists

trying to find the
perfect formula

for that lifesaving vaccine.

It was a Saturday morning,

and now you have

what are considered
to be ants in your pants

around getting your
experiments started.

All vaccines have the same goal,

whether they're made from
weakened or dead pathogens

or pieces of them.

Vaccines work

by giving our bodies, and
specifically our immune systems,

a preview of what an
invading virus would look like.

The idea is to trick the body

into thinking it's
being infected.

Typically and historically
what has been done is,

by giving the body just a
weakened form of the virus,

so that the body makes
an immune response,

but the person doesn't get sick.

But creating weakened viruses,

like the one used in
the measles vaccine,

can take years.

To speed things up,
dozens of labs are betting

on revolutionary new
approaches to vaccines,

building them with
genetic instructions,

sometimes in the form of RNA.

RNA is used by cells
day in and day out.

The purpose of
RNA is to tell the body

what types of proteins to make.

In this case, an RNA vaccine
would tell the body to make

the coronavirus spike protein.

At the end of the day, you're
really just calling up the cell

and saying, "Hey, cell,
can you make this protein

so my body can make
an immune response to it?"

The hope is that
our immune cells

would identify the
spike as a foreign threat

and trigger the
production of antibodies,

as well as memory cells.

They'll remember that
spike protein well enough,

and in so much detail,

that when your body sees
that spike protein again,

those memory cells can
trigger the body to respond

in a very specific
and quick manner

so that you don't get infected.

Many researchers... including
Corbett and Rhiju Das...

are focusing on RNA
for one critical reason.

The advantage of RNA vaccines
is that they're super-fast to make,

which is absolutely critical in
the current pandemic situation.

Though this approach is fast,

no one knows if it
will actually work.

There are not yet
FDA-approved RNA vaccines

that have gone on the market.

It's still not clear whether
these RNA molecules

will be safe to
inject into everybody.

In the past, there have been
a few experimental vaccines

which made infections worse.

That's why clinical
trials are so important.

In March, just over two months

after the coronavirus
genome was released,

volunteers in Washington
state started receiving

the experimental RNA vaccine
Kizzmekia Corbett helped design.

To get into a
phase-one clinical trial

66 days after the sequence
of a virus is released

is, you know, a world
record; it is incredible.

But even if an RNA
vaccine passes clinical trials

in record time,

there will still be other major
hurdles, including shelf life.

The current RNA vaccines
are stable if they're freeze-dried

or kept under
ultra-cold temperatures.

But at room temperature,

or even in a standard

refrigerated
shipping container...

These RNA vaccines,
they're gonna decay.

They seem to lose
their potency as vaccines

on a timescale of days.

Their expiration
date is so short

that they wouldn't be
active in the time it takes

to ship them from, say, Newark,
New Jersey, to California,

and down to the clinic
for me to get the shot.

That's a problem when the goal

is to manufacture and
deliver coronavirus vaccines

to billions of people
across the planet.

To find a solution,
Das's team is trying

to custom-design
the RNA molecules

so they'll fold into
more stable shapes.

What we're doing here is,

we are designing
these RNA vaccines

to fold into little
tiny packets.

But we don't know exactly
what the right shape is.

To find the right shape,
Das is recruiting help

from an unlikely crew...

online gamers.

We're trying to recruit
potentially millions of people

to come play a video game.

Some players' solutions
to molecular puzzles

are tested in Das's
lab with real RNA.

And the solutions
that they're providing

very well could
become a medicine

that then is injected
into billions of people.

RNA isn't the only new
contender in the vaccine race.

Through here is...

Dan Barouch's
lab has spent years

developing DNA
vaccines against H.I.V.

Now his team is applying
a similar approach

to the coronavirus...

creating a DNA vaccine that
codes for the spike protein

and relies on a common
but powerful helper.

We inserted the coronavirus
spike protein DNA

into a common cold virus.

Common cold viruses are
very good at getting into cells.

So we essentially
hijack that property

of the common cold virus

and utilize it to help get

the coronavirus
spike protein gene

into human cells.

Barouch hopes that
clinical trials of this vaccine

will start in September.

There are over three
dozen different vaccines

that are moving into preclinical
and clinical testing already.

The pace is really inspiring.

We have never seen this
for any other pathogen to date,

where so many different
vaccine developers

are really ready to go to
come up with a solution

to this particular
infectious disease.

Hopes are high that one or
more of these vaccines will work

and help end the pandemic.

But testing and manufacturing
vaccines can take years,

and there are no guarantees.

Without a vaccine,
the main tool we have

is our behavior.

In Wuhan, an unprecedented
reopening experiment

officially begins on April 8.

Residents are allowed
to travel and move about.

Every time I went
downstairs to shop for food,

I noticed there were more
and more people outside.

That was a very good sign.

But it's hardly back to normal.

Fear of a second
outbreak runs high,

and many restrictions
remain in place.

Anyone entering or leaving
a building or public space

is required to use their phone

to scan special
location-marking codes.

The gate of your complex

is the first checkpoint
you need to go through

when you try to go out.

Using apps like
WeChat or Alipay,

you scan the QR
code and tell the app

if you are entering or exiting.

The system records your
location automatically.

Based on your current health
condition, you're given a code.

Anyone with a green code
is allowed to leave freely,

but if you have a
yellow or red code,

which means you've had
contact with someone infected...

or you're infected...

you can't go anywhere.

At the same time, monitors
take body temperatures

at each access point.

These measures
have been introduced

to squash new outbreaks.

They track each
person's movements

in order to alert them later

if it turns out they were
exposed to the virus.

If someone who
was in the same place

at the same time as you

is diagnosed later,

you'll get a notice immediately.

Then your status becomes yellow,

and you have to isolate
yourself at home for a while.

In that instance, the
person notified is flagged,

and if they try to scan
into a public place

during the next seven days,

they will be denied entry.

It's all very strict now,
but it's for our safety.

And after being
very sick, scared,

and locked down for weeks,

Liu is relieved to
be out and about,

no matter what the restrictions,

just grateful to be healthy.

I want to say one more thing.

This outbreak really
taught me something.

People are precious.

Cherish everything you have,
be kind to everyone you met.

Months after the
initial outbreak,

the true origin of the
virus is still unknown.

Wuhan has dramatically
reduced the rate of infection,

though the virus still remains.

Today in Wuhan, China,

the city at the epicenter
of the coronavirus crisis,

it's reporting its
first new case

in more than a month.

So far, China's approach

appears to be
slowing the spread.

Back in the U.S., as COVID
infections continue to rise,

pressure mounts to
reopen the economy.

But are we willing
to go as far as China

to prevent new
waves of infection,

which some experts
say are inevitable?

Or will data collection
to track the virus

face a backlash over
privacy concerns?

We have never seen a
Silicon Valley product launch

quite like the one on Friday.

In response, Google and Apple
have developed new software

that anonymously
tracks COVID exposures.

They are teaming up to create

voluntary coronavirus
tracing and tracking software.

It allows a user's phone

to broadcast changing
codes to phones nearby.

If a person is later
diagnosed with COVID-19,

everyone using the software
who was in close proximity

in the previous two weeks

is notified that
they've been exposed.

No one's identity is revealed.

It's a voluntary program
that could slow the spread.

But many experts agree

this tiny virus remains
an enormous threat.

So, until we have effective
treatments and vaccines,

how do we stay safe?

Lifting the lockdown
is not the end.

It doesn't mean we
go back to normal.

It means that our
lives are altered,

at least in the medium
term, and potentially forever.

What we have to figure
out is, how do we get back

into not being
in total lockdown,

but at the same time,

minimizing the impact
that this virus might have?

But it's not going to be easy.

Hello! Hello!

♪ Happy birthday to you ♪

♪ Happy birthday to you ♪

One of the hardest
parts of this disease

is how we are so
separated from each other.

♪ Happy birthday to you ♪

And I think it underscores
for me the importance

that it's not
social distancing...

it's physical distancing
and social cohesion.

We still have to
connect with each other.

And pandemics like COVID-19

tell us how interdependent
we are on each other.

Truly, an outbreak anywhere
is an outbreak everywhere,

because we are connected.

Every part of the world
is about two flights away.

The pandemic has crystallized
a sense of purpose for us.

We're at a point where
really every day counts.

It's a horrible
situation to be in,

but the technologies

that we can develop
against the coronavirus,

we'll be able to deploy it

hopefully to prevent
any future pandemic.

And it's our legacy.

It's not just how we get
through the pandemic,

but what we do
about it afterwards.

We can't let this happen again.

And to me, this
is like a moonshot.

Imagine one day, if we
could take away the threat

of these kinds of pandemics
from happening again.

That would be a gift to
our, our kids and grandkids,

second to none.