What is mRNA Vaccine? Let's understand it simply

With the COVID-19 pandemic, a word that almost all of us have heard and that has become very close to our lives is 'mRNA vaccine'. You may remember this word being frequently mentioned with names like Pfizer and Moderna. Some people spoke very well about it, while others were a little scared of this new technology. So what exactly is an mRNA vaccine? How does it work inside our bodies? How is it different from a regular vaccine? Is there anything to be afraid of? Let's talk about all this simply, in a way that you can understand.

What is an mRNA vaccine, simply put?

Simply put, an mRNA vaccine is a preventative treatment that teaches, or trains, our bodies to protect themselves from disease. A doctor or trained health worker gives it to you as an injection with a needle.

The only mRNA vaccines approved for use in the world so far are for protection against COVID-19. You may remember these two names well:

• Comirnaty® (this is the Pfizer-BioNTech vaccine we all know)
• Spikevax® (this is the Moderna vaccine)

But this technology is very powerful. Scientists are already researching whether this mRNA technology can be used to make vaccines for other infectious diseases, as well as diseases like cancer. This means that we may get great benefits from this technology in the future.

Okay, so what is this mRNA?

Although this may sound a bit scientific, I'll explain it to you with a very simple example.

Think of the DNA in your body as a very valuable, master book in a large library. This book contains all the instructions and recipes needed to build your body and keep it functioning. This master book is so valuable that it is not allowed to be taken out of the library, nor is it allowed to be copied. It must be kept safe.

Now this is where mRNA comes in. mRNA is short for "messenger Ribonucleic Acid." It's like a 'messenger.' What it does is it goes to the main book (DNA) in the library and writes down on a piece of paper a copy of the recipe (instructions) for making the protein that the body needs at that moment. Then it takes that piece of paper and goes out of the library, into the kitchen of the cell (which we call ribosomes).

The cooks (ribosomes) in the kitchen look at the recipe (mRNA) that the messenger brought and make the protein exactly as it was written. When the job is done, they tear up the piece of paper with the recipe written on it and throw it away. They don't keep it.

How do mRNA vaccines work in our bodies?

Like all other vaccines, an mRNA vaccine trains our body's immune system to recognize an enemy (like a virus) and produce the weapons needed to fight that enemy.

Let's see how this happens in the COVID-19 mRNA vaccine:

1. Giving instructions: When you get the vaccine, your cells are given the 'recipe' (mRNA) for making the spike protein , the spike-like part of the SARS-CoV-2 virus that causes COVID-19. Remember, this is not the whole virus, or even a piece of it. It is only the 'instructions' for making it.

2. Cells make the protein: Our cells read that instruction and start making spike proteins. These proteins are displayed on the surface of our cells.

3. Activation of the immune system: Now our body's defenses (the immune system) see this new spike protein and get worried. "Who is this stranger? This is not one of us," it thinks, and identifies it as an 'invader'.

4. Weapons: Then the security forces start making special weapons to fight against this enemy. These weapons are what we call antibodies . They also make a type of 'memory cells' that can remember this enemy.

5. Destruction of the instruction: Just like we read a message and tear it up and throw it away, our cells take the instruction from this mRNA and completely destroy it within a few days. It does not remain in our body, nor does it integrate with our DNA. This is something that many people misunderstand.

Now imagine that the real COVID-19 virus has entered your body. This virus is no stranger to your immune system. They have already seen the spike protein of this virus and are ready to fight it. Therefore, they can quickly destroy the virus before it spreads in your body. This is what protects you from getting seriously ill.

What is the difference between traditional vaccines and mRNA vaccines?

The main difference is in the way our immune system recognizes the enemy. To understand this more easily, let's look at this table .

Are all vaccines for COVID-19 mRNA?

No. For example, the COVID-19 vaccine called Novavax® is not an mRNA vaccine. It is a protein subunit vaccine. That is, it injects pieces of the spike protein of the SARS-CoV-2 virus directly into the body.

What happens when you get the vaccine?

This process is very simple, and if you've had a shot before, this is the same.

1. A healthcare worker will clean your upper arm (or perhaps your thigh for young children) with an alcohol swab.

2. Then the injection is given with a very fine needle.

3. Apply a small amount of plaster to the puncture site.

The most important thing is that you will be asked to remain still for about 15 minutes after the injection. This is to check for any sudden, severe allergic reactions. If you are a person who feels a little dizzy or scared of needles, it is best to sit down during this time.

What are the advantages of mRNA vaccines?

There are two main advantages of this technology.

• Rapid production: To make traditional vaccines, the virus needs to be grown in a laboratory. This takes a long time. But in mRNA vaccines, the virus doesn't need to be grown. Once the genetic code of the virus is known, the corresponding mRNA can be quickly produced. Therefore, when a pandemic strikes, large quantities of vaccines can be produced in a matter of weeks, rather than waiting for months or years.

• Protection over not getting vaccinated: Getting any COVID-19 vaccine, especially an mRNA vaccine, gives you these benefits compared to someone who hasn't been vaccinated:
• Reduced risk of COVID-19 infection.
• Even if infected, the risk of becoming seriously ill and hospitalized is greatly reduced.
• Reducing the risk of developing long-term COVID conditions after recovering from COVID-19.

What are the risks and side effects of mRNA vaccines?

Like any medication, mRNA vaccines have minor side effects and very rare allergic reactions. It's important to be aware of these.

When should I see a doctor?

This is very important.

If you have any further questions about this vaccine, or if you are unsure whether this vaccine is compatible with your other medical conditions, don't hesitate to talk to your family doctor. He or she will explain everything to you and give you the right advice.

What is the history of this mRNA technology?

Although it has suddenly become popular due to the COVID-19 pandemic, this mRNA technology is not something that was discovered yesterday. It has decades of research history behind it.

• Basic research on mRNA technology began in the 1970s.
• It was in the 1990s that scientists first tried to see if it could be used to produce vaccines.
• But there were big challenges at the time. The mRNA molecule is very fragile. Once it's in the body, our immune system destroys it. And there was no way to get it into cells.
• After more than 20 years of research, scientists have found solutions to these problems. They learned to create a coating of tiny fat particles (lipid nanoparticles) to protect the mRNA molecule. This is what is used in today's vaccines.
• Finally, in 2018, a drug called patisiran was approved to treat a rare neurological disease. The same method used to deliver RNA into cells later paved the way for companies like Pfizer and Moderna to develop COVID-19 vaccines.

It's normal to be a little afraid and skeptical of new things, especially in medicine. When something comes along that's different from the old methods we're used to, it's hard for us to immediately believe it. But this mRNA technology is something that thousands of scientists have developed over decades and has proven to be safe. This is why, when a serious pandemic comes, we were able to create safe, effective vaccines in a matter of months, rather than waiting for years.