O QUE NÃO TE FALARAM SOBRE AS VACINAS - Nostalgia Ciência

[Howling] What are you still doing here Paul? Weren't you on your way to get vaccinated? I was, but I got very scared Laster!

Scared of what? From the needle? No, I've seen on the internet that vaccines can make you sick.

Did you know that Laster? Oh, my God Paul! You have to stop believing these fake news you get in the penguin's group.

I'm sure that conky guy will sort it for you. Mirror to the TV. Can vaccines cause autism?

Are you taking a huge risk when vaccinating your child? Well, at least that's what the 1998 article from Lancet magazine by the doctor Andrew Wakefield says. But, is this true?

Did he have concrete evidence to support this saying? Let's find this out in the new episode of Nostalgia Science! [Introduction] Hello, my dear friends, how are you?

My name is Felipe Castanhari and this is another Nostalgia Science, Where we show that Science can be a very entertaining! We've already been to space, looking for black holes. We visited the era of the dinosaurs to see how they got extinct.

But today, let's talk about something much more present in our lives: Vaccines. The act of taking an injection is not cool at all, right? I do not know anyone who likes it.

However, practically everyone has already gone through this. But do we really have to go through this? I've heard around, I'm not sure.

. . that the vaccines have side effects still unknown!

That vaccine-preventable diseases are almost totally eradicated! And besides, they put mercury in the vaccines and this can cause autism! Calm down, guys.

Calm down! The first thing we have to do here is to understand how a viruses work. We hear about it all the time.

But what is a virus? Before I show you here I need to be careful right? Okay, now that I'm properly vaccinated, meet the terrible, monstrous, ruthless and tiny.

. . Virus!

But I ask that you be very careful, do not get too close to the virus, don't even touch the screen of the computer or smartphone, because this virus here is very dangerous. After all we are not talking about a common virus, but the Smallpox virus! First let's understand its size.

Viruses are very tiny. Smaller than a bacteriae! We can only see him under the microscope.

And being so small makes it easy to get into our body and it has several ways of doing it. For example, when we get wounded. Or through contact with our eyes, nose and mouth.

Once in our body, this virus needs to enter a cell so that it can multiply and survive. And he does this by lodging inside the cell. It's like he inserts a fake key into the 'lock' of the cell.

Each type of virus has its preferred types of cells. Therefore, each of them causes a different disease. Like measles, influenza, mumps or smallpox.

This little pox virus here beside me has killed millions of people in the history of the world. And the way he acted was something on the level of horror films. The person infected with this virus began to have symptoms similar to a very strong flu like fever and body aches.

But in the case of the smallpox virus, this was just the beginning. Because after a few days he began to attack other parts of the body, such as the digestive system, causing nausea and vomiting. But the best known signs of smallpox happened when the virus began to attack the skin cells, making blisters appear on the persons body.

First they started on the mouth but then they expanded to the whole body and when they burst, they would become wounds. People who got sick with smallpox and survived often became disfigured, their skin destroyed and full of marks. And of course, thinking only of those who survived wich were very few, because the disease has made more victims than many people imagine.

In the twentieth century, this virus has killed 300 to 500 million people worldwide! That was only in the twentieth century. There are studies that point out that the first recorded cases of the disease may have arisen in the sixteenth century.

So this enemy threatened humanity for centuries, until finally it began to be fought by science. And believe me or not. .

. It all started with a scientist who got near cows! At the end of the 18th century, several people said that those who worked with cattle did not contract smallpox.

And an English doctor named Edward Jenner 'rolled up his sleeves' and decided to end this mystery. Watching a group of women who worked milking cows, he realized that they didn't really catch the same smallpox that killed other people, but a lighter version of the disease. They had only a few blisters on their hands and nothing else.

Edward Jenner also discovered that the cows had this same lighter version of smallpox. Jenner realized that in this coincidence was the reason that smallpox did not develop so aggressively in those women. And so as a good scientist, he decided it was time to prove his theory.

The first thing he did was to get samples of the blisters from one of the women's hands and contaminate a healthy boy with it. The boy had a bit of a fever, some blisters, but soon got better. After a few weeks, he exposed this boy to real smallpox, the one that killed everyone.

And the boy did not catch the disease. Jenner repeated the experiment in other boys, even in his own son. And he concluded that whoever was exposed to a milder version of smallpox could develop immunity to the disease.

This mild version of the disease was bovine pox, which had the scientific name Variolae Vaccinae, because 'vaccinae' is the Latin word for 'cow'. So the process of getting immunized from bovine pox became known as the vaccine years later! Today we have vaccines against various diseases and they are not all made from bovine pox!

I am talking about polio vaccines, meningitis, hepatitis, measles, chicken pox . . .

These vaccines are made from weakened viruses, dead microbes and sometimes also bits of these microorganisms. So imagine that for some vaccines, only a small amount of the virus is enough to activate your immunoglobulin. And they do not rest after just fighting the virus.

They 'study' how to defend the body by creating an immune memory that will protect you in the future! This is the body of a person who has never been vaccinated. It is exposed to several types of diseases it does not know, such as measles.

If the virus that causes measles gets into this body it will multiply and become even stronger. When your body notices the invader, it may be too late and you will already be sick. And that's when the vaccine comes in which functions as a kind of teacher, teaching your immune system about that virus so that it learns to defend itself.

Using the measles vaccine as an example, doctors have put in a controlled way a weakened version of the measles virus which serves to activate your immune system. In this process, our body not only faces the threat but also learns how it works creating barriers against further attacks. So when the measles virus re-enters your body it will 'remember' and destroy it before you get sick.

And of course this doesn't just happen with measles. Our body has an immune memory and remembers many viruses and bacteriae that have passed through it. But this doesn't work for all diseases.

In some cases, such as tetanus, the vaccine literally loses its validity after a few years so a new dose is needed. A pinch on your arm is just enough. Your body has already remembered all about the disease again.

But Castanhari, what about the flu? Every year I need to take injection? Why?

You may have noticed that every year there is flu vaccination and that even if you get vaccinated one year you need to get the vaccine the next year. This problem is not in the body's memory but in the influenza virus that is highly mutable that means it mutates very easily. When your body learns to deal with it the virus goes away but comes back after a time with a different face and then your body needs a new vaccine to learn how to deal with it again.

Of course, some vaccines cause side effects but that changes from person to person and those symptoms are much weaker than if you actually got the disease. Now listen to this: When you get vaccinated, you're not only protecting yourself from the disease but helping to fight against it. It's simple, the more people are protected from a virus the harder it is for it to spread, to the point that it can eventually disappear.

Thanks to the vaccine discovered by Edward Jenner, and an effort from several countries, the smallpox that killed millions of people for centuries was completely eradicated from the planet in the late seventies. You young people, you are part of the first generation of people in the whole history of humankind who need not worry about dying because of smallpox. The people of ancient Egypt would be jealous of you.

But is what about vaccines causing autism? Well, bad news is that a lot of people have been looking at the vaccines in a negative way. In fact, there are people who are anti-vaccines.

Some parents claim that the triple viral vaccine that prevents measles, mumps, rubella, they say it can cause autism and so they choose not to vaccinate their children. But is that true? Actually this autism thing started with the doctor Andrew Wakefield who published a study on this in the late nineties.

This study published in The Lancet described a casual link between the MMR vaccine which protects against measles, rubella and mumps and the development of autistic behaviors in some children. But a few years later, they discovered that he had forged the search results and so he even lost his medical license. He is no longer a doctor, he can never be a doctor again.

Besides that, they found that prior to the publication of their article in 1998 the pseudo-physician had filed in a patent application for a measles vaccine. That means actually he just wanted to harm the credibility of the MMR vaccine saying that it caused autism so that he could take this part of the market for himself. This whole story was clarified in 2004, but reverberates to this day.

Science never found any evidence that the triple vaccine was linked to autism. Even though, any basic study would show that since the vaccine began to be applied in the seventies autism cases would have increased, right? But it didn't happen.

But even so this story unfolded in another rumor about the vaccines. In 2009, at the time of the H1N1 pandemic there was a rumor that the vaccine against the disease could cause autism because of a business called Thimerosal, which is a preservative used in several vaccines and contains mercury in its components. After that, every time the flu vaccination happens this story goes shows up in social networks with people saying that the vaccine's mercury causes autism but that, guess what, is also a hoax.

Mercury has been used as a preservative in vaccines since the 1930s. And science has never been able to prove any harm it has done to people's health. Firstly because its concentration in vaccines is low.

And secondly because the mercury is expelled from the body very fast. Brazil has been able to reduce its infant mortality that is, to reduce the number of children who die due to vaccination. But this fight is far from over.

A few months ago, we had a measles outbreak in Europe, with more than 41,000 cases. So . .

. how about getting vaccinated, guys? Because for the virus, it does not matter whether you believe in it or not.

Thank you to all who watched Nostalgia Science thank you for your audience. And as I always say, remember: "Always be curious! " Thank you!

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