from the coronavirus pandemic,

many are doing their part by social distancing

and self-isolating.

But as the virus and disease progress,

one big question on many people's minds is,

what can we expect with regards to a vaccine?

- So, there are a ton of fascinating things

happening right now and tireless research

looking into a vaccine.

But in order to understand it,

we must first talk about how vaccines work.

It was in the year 1796

that the first official vaccine was created

by Edward Jenner.

He took a bit of the cowpox virus

and injected it into a small boy.

He later was able to confirm

that that boy did not develop smallpox,

which was a related virus.

So, how exactly did this work?

Typically, when you get infected with a virus,

it begins taking over your cell's machinery

in order to make copies of itself.

But these actions eventually trigger an immune response.

Your body begins creating special cells

like macrophage, B cells and T cells,

that not only try and destroy the pathogen

but also store information about it.

What it looks like, the best way to defeat it, and more.

This part is specially important

because if the virus ever comes back again,

your body can be immediately prepared to attack it.

But the body takes time to do all of this,

and so, if a virus gets enough of a head start

or attacks somebody with a compromised immune system,

it can gain the upper hand,

leading to illness or death.

- This is where vaccines come in.

There are many different types,

but the goal of them all is

to prep and train your immune system

before you get an infection.

It's like a practice run.

That way, when your body is invaded by the real virus,

it has an advantage because it already knows

how to take down the invaders.

Most vaccines work by injecting some aspect of a virus

or bacteria into your bloodstream,

depending on what strain you're trying to protect against.

We're gonna focus on viruses today.

Once administered into the bloodstream,

even though it's not the real virus,

the body reacts as thought it's a real threat.

macrophages engulf the pieces,

allowing T cells to recognize and bind the foreign antigen,

causing them to replicate into all different kinds

of immune cells

and trigger something called memory cells.

These stick around even after the body is done fighting,

and it's these memory cells that allow for a quick response

if and when the real virus shows up.

- The effectiveness of vaccines have allowed us

to nearly eradicate diseases like measles,

until, of course, the recent vaccine hesitant movement

in which kind of came back.

Regardless, they are extremely powerful tools

to provide immunity to the individual

and to protect larger communities,

and, in our ever-connected world, all of humanity.

Now there is more than one type of vaccine.

Live attenuated vaccines like measles, mumps, and rubeola

introduce weaker or asymptomatic forms of the virus

into your body,

which are very effective but can't be given to people

with compromised immune systems.

Inactive vaccines like polio or hepatitis A

use dead pathogens that have been killed

by heat or chemicals.

These can be used on people

with already weakened immune systems.

However, they aren't great for long-lasting immunity

because they don't stimulate the real thing

quite as well as live attenuated vaccines

and often require several doses.

Subunit vaccines like hepatitis B or influenza

use a specific protein or carbohydrate from the pathogen

that will still trigger an immune response.

There are some other experimental DNA vaccines,

but perhaps the most relevant

is a promising new technique of vaccines

called mRNA vaccines,

which you may have heard about recently.

That's because they are currently in development

and have begun testing on humans

to potentially fight the spread of Covid-19.

- The private company Moderna has created a vaccine

called mRNA-1273

and has enlisted 45 healthy adults

to start receiving the vaccine.

This is unprecedented because they've skipped

the typical years of animal testing

and instead are doing it at the same time

as their human trials.

But experts believe they received permission

because they're not actually inserting

a modified virus into individuals,

but rather a sequence that codes

for the tiny protein spikes that are on the virus

that connect with human cells.

The hope is that this mRNA will get processed in your cells

and have them making the spike-like protein

that will be on the virus,

which would then trigger your immune system

to kick into action and ultimately have your body prepared

for when the real thing happens.

They were able to get ahead on building this thing

because of Chinese scientists

who sequenced the genetic material

of SARS-CoV-2,

the virus that causes Covid-19.

This information was publicly released in January

which has helped labs around the world

start to test and build out vaccines.

SARS-CoV-2 shares between 80 to 90%

of its genetic material with SARS,

the virus we know about from 2003.

Both consistent of a strip of ribonucleic acid

inside a spherical protein capsule

that is covered in spikes.

- This means that some of the vaccine information

is able to take up where the SARS vaccine left off,

and I know we have said

that they have already started to give this to humans

but this is only to test safety,

to make sure there's no negative effects,

and to see if it actually creates the antibodies.

Clinical trials usually take place in three phases,

and the first phase is to test for safety

and make sure there's no negative adverse effects.

The second phase is to test for efficacy,

and usually you give it to a larger amount of people

in a place where the disease has taken hold.

For example, they're doing it right now in Seattle.

The third phase is to continue this testing

in a larger expansion,

now looking at thousands of people.

If the vaccine does appear to be safe,

Moderna is gonna ask the FDA

to move on to the second phase

before the first phase has technically even finished.

You can start to imagine how long this is going to take.

As you give people these experimental vaccines,

you can't just then give them the virus and the disease.

You have to let them go out and live their lives

and see what happens when they may be contracted,

when they maybe don't.

You have to look at tested individuals

next to control groups, people who didn't get the vaccine,

and start to see what happens.

Does it even work, does it make people unhealthy,

does it do nothing?

For example, in 2004, when a SARS vaccine was being tested,

vaccinated ferrets developed

damaging inflammation in their lungs

after being infected with the virus.

Approval can be accelerated

if regulators have approved similar products before,

which is how the flu vaccine is so well designed

and modulated to be updated yearly.

- But the SARS-CoV-2 virus

is a novel pathogen in humans,

which means many of the technologies

that are being used to develop the vaccine

are relatively untested.

There are hundreds of labs all around the world

making amazing headway when it comes

to treatment and vaccines,

some even repurposing SARS vaccine research

and hoping to start clinical trials in the spring.

Shout out to the Canadian scientists

who isolated the SARS-CoV-2 virus

which will inevitably help

in terms of finding treatments and vaccines

going into the future.

- Truthfully, it usually takes decades to make a vaccine.

Every stage takes time, from sequencing the genome,

to isolating the virus, to testing in vitro,

to then testing in animals,

going from mice to non-human primates,

to starting those phases we talked about earlier.

Phase one for safety, phase two for efficacy,

phase three for expanding it out,

before even asking for a license,

and then thinking about how to make enough of the vaccine

for an entire population.

All of this to say that experts believe

that with record-breaking time

we can get a coronavirus vaccine within one to two years.

Some hopeful people who think on the bright side of life

and are actually thinking about

some of these more experimental ways of making vaccines

think we can get one as early as eight months,

and some more conservative estimates

have it at longer than two years.

Even the vaccine that's already gone into human trials,

the one we talked about from Seattle,

the company Moderna,

that is likely still going to take a year.

And it's also important to remember

that it's a private company

and therefore they have private interests,

so these really exciting headlines

do in fact help their stock.

Either way, these short timelines come with risk,

not to mention that many countries around the world

are trying to develop their own versions of these vaccines

and if they get somewhere

they're going to inoculate their own populations first.

It will be a long time before we have a vaccine

that is able to be used on the world's population.

- We say all this not to discourage people

but to help understand realistic timelines.

We even have some friends that have said things like,

"Oh, we'll be out of this once they get a vaccine

"in a couple weeks."

And it's like, it doesn't work like that.

Might we create therapeutics and relief

for those who are infected?

Yes.

And might we see a record-time vaccine that comes out?

That's totally a possibility as well.

But we can't count on it to solve our immediate issues.

And is it possible that we may never see

a Covid-19 vaccine?

That is a possibility as well.

- It all really emphasizes the constant need for research

and funding of the sciences.

After the SARS epidemic of 2003 sort of died down,

a lot of that research and funding money

was taken out of that vaccine,

which is disappointing because

all of that research and money

if we had continued to fund it

would have been extremely helpful right now.

There is now SARS vaccine because once it died down

that research and funding was cut.

When this pandemic eventually dies down,

we need to remember our lessons of the past,

which is that we need to continue

to fund science and research

and make sure that when these things happen again

we are more prepared.

We'll say it now and we'll say it again,

and that is that you need to vote for science.