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How mRNA Vaccines Work - Simply Explained

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    Developing vaccines is usually a very lengthy process.
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    Taking, on average, 8 years to get approved.
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    Since a few years, we have the ability to create mRNA vaccines which can be developed
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    much faster.
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    So how do these vaccines work?
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    Are they safe?
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    And, how do they compare to traditional ones?
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    But first, you must understand how the immune system works.
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    When a virus enters your body, it will attach itself to one of your cells and inject its
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    DNA or RNA into it.
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    This is like a blueprint for your cells: containing instructions on what the cell has to make.
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    So, in this case, the virus's RNA will tell your cell to make more copies of the same
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    virus.
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    They become virus factories, pumping out new copies of the virus that can infect even more
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    cells.
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    Naturally, our bodies have a defense system for foreign intruders.
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    The immune system attacks any protein, virus, or bacteria that do not belong in our bodies.
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    But it takes a few days for it to learn how to attack the intruder.
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    Meanwhile, the virus factories are running non-stop, quickly replicating the virus and
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    spreading it in your body.
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    In other words: you start experiencing symptoms of whatever has infected you.
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    After a few days, however, your immune system has figured out how to attack the virus and
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    will start to produce antibodies.
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    These attach themselves to the virus, preventing them from infecting more cells and marking
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    them for destruction.
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    As you can see, the immune system is remarkable, but it's also slow to mount an attack.
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    That's the reason why we get sick in the first place.
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    So to give it a helping hand, we developed vaccines.
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    The main idea is to train your immune system to recognize and fight off an infection before
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    it has occurred.
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    Almost like showing your immune system a mug shot of the virus and saying: "if you see
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    this, kill it."
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    There are various types of vaccines, but let's take a look at mRNA vaccines, the new kid
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    on the block.
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    To understand how they work, let's take the COVID19 pandemic as an example.
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    You might have seen pictures of the virus, with its distinctive spikes.
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    These spikes allow the virus to attach to specific cells in your body (ACE2) and infect
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    them.
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    Now here's the key idea for the COVID19 vaccine: what if we could train our immune system to
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    recognize these spikes by having our body produce them?
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    To do that, researchers took the virus's blueprint, its RNA, and isolated the part responsible
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    for producing the spikes.
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    Armed with this blueprint, they created mRNA or messenger RNA.
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    This is a special form of RNA that can enter your cells and give them instructions.
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    In this case, the RNA contains instructions to build the spikes of the coronavirus, not
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    the virus itself, just the spikes.
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    So mRNA vaccines contain instructions for your cells that tell them to build a part
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    of a virus in large volumes, almost like giving them a recipe to follow.
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    Once this is happening, your immune system kicks into action and start learning how to
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    attack these intruders.
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    Again, it takes time for the immune system to fight off these spikes, but you won't get
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    sick because it's only the spikes, not the virus itself.
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    And that's it!
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    Your immune system has learned how to attack the spikes of the coronavirus.
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    It destroys all the spikes and even breaks down the mRNA vaccine itself.
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    The only thing left in your body are special "B cells" or memory cells.
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    These can linger around for months or years until the same virus infects you again.
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    When that happens, the B cell can produce the correct antibodies right away, preventing
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    the virus from spreading and making you sick.
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    What's interesting about this mRNA technique is that it's relatively quick to develop a
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    vaccine as soon as we know the DNA or RNA sequence of a virus.
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    And secondly, because the vaccine only makes our body produce a part of a virus, we can't
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    get sick.
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    More traditional vaccines use weakened versions of the actual virus.
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    This also triggers an immune response but could also give you mild symptoms.
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    Now you know how mRNA vaccines work, what about their safety?
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    The biggest misunderstanding about this technology is that the mRNA in the vaccine can enter
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    our cells and changes our very own DNA.
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    But that's not true.
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    mRNA is very fragile and only survives a few hours in our bodies.
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    Just long enough to produce viral proteins, like the spike, and kickstart your body's
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    immune response.
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    After a while, your body will break down all of the vaccine's mRNA.
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    Another misconception is that they're unsafe because they were developed so quickly.
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    In the case of COVID19, it only took a few days to a first test vaccine.
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    It was this fast because some companies have invested a lot in mRNA technology and because
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    we already knew a lot about the family of coronaviruses.
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    But that's it for this video.
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    Now you know how mRNA vaccines work.
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    But don't take my word for it!
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    All sources used to make this video are listed in the description below.
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    Check it out if you want a more in-depth explanation.
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    Give this video a thumbs up if you found it interesting and consider subscribing to the
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    channel.
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    Thanks for watching, and till next time!
Title:
How mRNA Vaccines Work - Simply Explained
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Video Language:
English
Duration:
04:26

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