The Coronavirus Vaccine Explained | COVID-19

Summary

This video delves into the development and importance of vaccines, focusing on Covid-19. It explains how vaccines work by training the immune system to combat viruses and discusses different types of vaccines, including traditional ones and newer mRNA vaccines. The video highlights ongoing research, particularly Moderna's mRNA-1273 vaccine, and the global race to develop effective vaccines against Covid-19. While acknowledging the challenges of vaccine development, the video emphasizes the importance of science, research funding, and the vital role of front-line workers during the pandemic.

Takeaways

• 🦠 Covid-19 is spreading, and people are practicing social distancing and self-isolation to help control it.
• 💉 Vaccines work by training the immune system to recognize and attack viruses before infection.
• 👨‍🔬 The first vaccine was developed in 1796 by Edward Jenner, using the cowpox virus to protect against smallpox.
• 🧬 When infected, the body produces immune cells like macrophages, B cells, and T cells to fight and remember the virus for future protection.
• 💪 Vaccines act as a practice run, helping the immune system prepare for the real virus by triggering an immune response without causing disease.
• 🧫 There are different types of vaccines, including live attenuated, inactive, subunit, and the promising mRNA vaccines, which are being developed for Covid-19.
• 🔬 Moderna's mRNA-1273 vaccine is in human trials, designed to trigger an immune response by encoding the spike proteins found on the virus.
• ⌛ Developing vaccines typically takes years, with three clinical phases to ensure safety and effectiveness before mass production.
• 🌍 Labs worldwide are collaborating on Covid-19 vaccines, using SARS research to accelerate progress, though it will take time to roll out globally.
• 📢 It's crucial to continue supporting science, research, and public health measures like physical distancing, handwashing, and reliable information sources.

Q & A

What is the historical significance of Edward Jenner's work in vaccine development?

Edward Jenner created the first official vaccine in 1796 by using the cowpox virus to inoculate a boy, later confirming that the boy did not develop smallpox. This laid the foundation for modern vaccines.

How does the immune system respond to a viral infection?

When infected with a virus, the body triggers an immune response by creating macrophages, B cells, and T cells, which destroy the pathogen and store information about it for future protection.

What is the primary purpose of a vaccine?

The goal of vaccines is to train the immune system to recognize and fight pathogens before infection occurs, allowing the body to respond quickly when exposed to the real virus.

How do live attenuated vaccines differ from inactive vaccines?

Live attenuated vaccines introduce weaker or asymptomatic versions of a virus, offering strong immunity but aren't safe for people with compromised immune systems. Inactive vaccines use dead pathogens and are safer for such individuals but often require multiple doses.

What are subunit vaccines, and how do they work?

Subunit vaccines use specific proteins or carbohydrates from a pathogen to trigger an immune response. Examples include hepatitis B and influenza vaccines, which stimulate immunity without the full pathogen.

What are mRNA vaccines, and why are they important in the fight against COVID-19?

mRNA vaccines, like Moderna's mRNA-1273, introduce genetic instructions that code for viral proteins, prompting the immune system to respond. This method is promising for COVID-19 as it doesn't use live virus and can be developed rapidly.

Why did Moderna's COVID-19 vaccine development bypass some traditional testing phases?

Moderna skipped some animal testing due to the urgency of the pandemic and the nature of the vaccine, which doesn't use live virus. This allowed for faster human trials to test safety and efficacy.

What are the three phases of clinical trials for vaccines?

Phase 1 tests for safety in a small group. Phase 2 tests efficacy in a larger group where the disease is prevalent. Phase 3 expands testing to thousands of people to ensure effectiveness and safety before seeking regulatory approval.

Why might vaccine development for COVID-19 take up to two years or more?

Developing a vaccine involves multiple stages, including safety and efficacy testing, and production scalability. Even with accelerated timelines, real-world testing and manufacturing take time, making a vaccine available for the global population a long process.

Why is it important to continue funding vaccine research after epidemics like SARS or COVID-19 subside?

After the SARS epidemic, research funding dwindled, delaying the development of vaccines that could have been useful during the COVID-19 pandemic. Continued funding is crucial to stay prepared for future outbreaks.

Outlines

00:00

💉 Understanding Vaccines and Their Historical Context

Mitchell explains the ongoing research into Covid-19 vaccines, emphasizing the importance of understanding how vaccines work. He gives a historical example of Edward Jenner's smallpox vaccine in 1796, explaining the immune response process, where the body creates cells like macrophages, B cells, and T cells to fight off pathogens. Vaccines prepare the immune system by simulating infections, helping the body build memory cells to defend against real infections more effectively.

05:01

🔬 Types of Vaccines and Their Mechanisms

This section highlights various vaccine types and their respective functions. Live attenuated vaccines use weakened viruses and are highly effective but unsuitable for people with compromised immune systems. Inactivated vaccines use dead pathogens and offer shorter immunity. Subunit vaccines use pieces of a virus to trigger an immune response, and mRNA vaccines, which are currently being tested, provide an innovative approach by triggering immune responses using viral protein spikes, making them a key area of Covid-19 research.

10:02

📊 Clinical Trials: Phases and Challenges

Clinical trials are explained in detail, focusing on the three phases: testing for safety, efficacy, and large-scale distribution. The Moderna mRNA-1273 vaccine has begun human trials, and while accelerated approvals are possible, the process remains lengthy. The complexity of clinical trials is emphasized, including the need for control groups and the risks associated with experimental vaccines, drawing comparisons to past issues like the SARS vaccine's challenges with animal testing.

🧪 The Global Vaccine Race

Global efforts in vaccine research are highlighted, mentioning how various labs around the world are repurposing SARS research to accelerate Covid-19 vaccine development. There are hopeful timelines, but experts caution that it may take 1-2 years before a vaccine is widely available. Some researchers predict earlier success, while others believe it will take longer. The competition among countries to develop their vaccines and prioritize their populations first is also discussed.

🔍 Realistic Expectations and Long-Term Preparedness

This section manages expectations about vaccine timelines and potential setbacks. The importance of continuing to fund scientific research even after the pandemic is emphasized, noting that past lapses in research funding, like after the 2003 SARS outbreak, left the world less prepared for Covid-19. The script encourages voters to support science-friendly policies and politicians to ensure better preparedness for future pandemics.

🧼 Flattening the Curve and Community Responsibility

Mitchell reiterates the importance of personal responsibility in combating the virus through physical distancing, hand washing, and following reliable sources of information. He underscores that while vaccine development is underway, immediate solutions lie in following health guidelines to flatten the curve and limit the spread of the virus.

🙏 Acknowledging Frontline Workers and Science Communicators

The script concludes with gratitude to essential workers, including healthcare professionals, researchers, and grocery store workers. Mitchell and Greg highlight their commitment to science communication during the pandemic, offering reliable information through videos and podcasts to help the public stay informed. They end by expressing appreciation for the public's role in spreading accurate scientific knowledge.

Keywords

💡Vaccine

A vaccine is a biological substance designed to provide immunity against a specific infectious disease by stimulating the body's immune system. In the video, vaccines are discussed as a crucial tool for preventing diseases like COVID-19, explaining how they train the immune system to recognize and fight a virus before infection occurs. The development of a COVID-19 vaccine is a major focus of the video.

💡Immune System

The immune system is the body's defense mechanism against pathogens such as viruses and bacteria. In the video, it explains how vaccines help the immune system by providing a 'practice run' so that it can more effectively combat actual infections. The video describes the role of immune cells like T cells and B cells in responding to threats.

💡mRNA Vaccine

An mRNA vaccine is a type of vaccine that uses messenger RNA to instruct cells to produce a protein similar to the one found on a virus, which triggers an immune response. The video highlights Moderna’s mRNA-1273 vaccine as a key example of this new technology being used in the fight against COVID-19. This experimental approach is discussed as promising, but relatively untested.

💡Clinical Trials

Clinical trials are research studies that test how well new medical interventions work in people, often in three phases. The video explains that Moderna’s COVID-19 vaccine is in human trials, describing the process to ensure safety and efficacy. It highlights the importance of these trials for understanding whether the vaccine can prevent infection and be safely used.

💡Flatten the Curve

Flattening the curve refers to slowing the spread of a virus to prevent healthcare systems from being overwhelmed. The video stresses the importance of social distancing and self-isolation to reduce COVID-19 transmission, thereby flattening the curve and buying time for medical research and vaccine development.

💡SARS-CoV-2

SARS-CoV-2 is the novel coronavirus responsible for COVID-19. The video explains the virus's genetic similarities to the earlier SARS virus from 2003 and how this information has helped accelerate vaccine development. It notes that Chinese scientists' early genome sequencing of SARS-CoV-2 was critical in launching vaccine research.

💡Live Attenuated Vaccine

A live attenuated vaccine contains a weakened form of a virus, which still triggers an immune response but does not cause serious illness. In the video, this type of vaccine is used as an example of traditional vaccines like those for measles, and contrasts it with newer types like mRNA vaccines, which are safer for people with compromised immune systems.

💡Herd Immunity

Herd immunity occurs when a large portion of a population becomes immune to a disease, either through vaccination or previous infection, reducing its spread. The video touches on the importance of vaccines not only for individual protection but for the health of larger communities, illustrating the role of herd immunity in preventing outbreaks.

💡Macrophages

Macrophages are immune cells that engulf and digest pathogens, such as bacteria and viruses. In the video, they are mentioned as one of the key players in the immune response triggered by a vaccine. They help break down the virus and present it to other immune cells like T cells, which then learn how to combat the virus in the future.

💡Spike Protein

The spike protein is the part of the SARS-CoV-2 virus that attaches to human cells, allowing the virus to infect them. The video explains that Moderna's mRNA vaccine aims to instruct cells to produce a spike-like protein, which would provoke an immune response and prepare the body to recognize and fight the real virus.

Highlights

Vaccines train the immune system before infection, preparing the body for when the real virus invades.

The first official vaccine was created in 1796 by Edward Jenner, using the cowpox virus to prevent smallpox.

Vaccines help the immune system recognize and respond quickly to future infections by creating memory cells.

Live attenuated vaccines introduce weaker forms of a virus, providing strong immunity but can't be used on immunocompromised individuals.

Inactive vaccines, like polio and hepatitis A, use dead pathogens and are safer for weakened immune systems but require multiple doses.

Moderna developed the mRNA-1273 vaccine for COVID-19, using an innovative approach by injecting mRNA that codes for virus spike proteins.

Chinese scientists sequenced the genetic material of SARS-CoV-2 in January 2020, helping fast-track global vaccine development.

Clinical trials for vaccines are conducted in three phases: testing for safety, efficacy, and expanded population testing.

The fastest possible timeline for a COVID-19 vaccine is 8 months, though experts estimate it could take 1-2 years.

SARS-CoV-2 shares 80-90% of its genetic material with the SARS virus, aiding vaccine research by building on previous work.

The mRNA vaccine approach focuses on getting cells to produce a harmless spike protein to prepare the immune system.

Therapeutics and treatments for COVID-19 may arrive before a vaccine, but the latter is essential for long-term protection.

Past pandemics, like SARS in 2003, saw funding for vaccine research decline once the immediate threat faded, delaying current solutions.

Vaccine development typically takes decades, but COVID-19 research is progressing at record speed thanks to global collaboration.

Science communication is crucial during the pandemic, with platforms like Twitter and Instagram helping disseminate accurate information.

Transcripts

- [Mitchell] As Covid-19 spreads

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.

You need to elect politicians who believe in science

and who listen to scientists when it comes to policy.

- In the meantime, this is why it's so important

that we physically distance and self-isolate

in order to flatten the curve,

wash your hands regularly and thoroughly,

and keep looking to legitimate sources

to keep updated on news and information as well as advice.

- This is an unprecedented time

and it is such an important moment in history

for science communication.

We really think it's amazing

how many people have made videos out there,

how everyone has sort of taken to Twitter and Instagram

to try and disseminate proper scientific information,

and for that reason we are thankful.

- I think we should also send a huge thank you

to everyone on the front lines of this,

whether it's healthcare workers.

Greg's sister is literally

a respiratory therapist. - Yeah, she runs ventilators.

Truly one of the most important people

in the world right now.

- And we really wanna see that there's

grocery store workers and clerks,

there's scientists and researchers,

there's everyone working at hospitals,

and so many more that have such important roles,

and we appreciate you so much.

- If you have any questions, let us know.

This is what we are gonna be working on right now.

- We are here.

- We are here. - For the foreseeable future.

- I mean, science communication is something we love,

we've been doing it for eight years,

but right now we're like, okay, we need to make sure

that people are getting the right information

and we have the ability to do that.

Was that enough of those?

- And the time, because we're literally self-isolating.

We also just put a podcast out about self-isolation

and research surrounding that,

so we'll leave a link.

- Make sure you're subscribed.

There's our mailing list below.

We'll see you soon for a new video.

- See you guys. - Peace.