The Side Effects of Vaccines - How High is the Risk?

  • Published: 12 May 2019
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    Vaccines are one of our best tools to prevent dangerous diseases, but they come with side effects. So would it be safer not to vaccinate?

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Comments • 76 254

  • Kurzgesagt – In a Nutshell

    Dive into sources and further reading here:

    Vaccines and their side effects are a hard topic to cover – we know we keep saying this, but this case especially, there were a lot of things to consider. You can’t blame people for being worried, so we wanted to take their concerns seriously.

    Because it is impossible to cover everything there is to know about vaccines in a ten minute video our sources are extra extensive and explain a lot of aspects in more detail, with an extra focus on further reading.

    So if you want to dive in deeper or have more arguments at hand for your next heated discussion, here you go.

    • toxicboi i
      toxicboi i  3 days back

      The people who dislike the video is probably Karen

    • grab america by huevos
      grab america by huevos  3 days back

      hey i was in the military got every shot except the hpv gardisal no they are not good for your body, why do they give a live attenuated virus in the flumist, why is everyone still sick a couple of days after the flu shot, why do i diagnosed with strep throat in the military if we are fit in the military, i had to get a penicillian shot in the butt, where the studies on the military with reactions to those shots? where results from the burn pits and poop pits from us veterans, why did we wear perithrin soaked uniform deployed "to keep bugs off" why did we stay in mosquito bombed buildings,

    • Nick Korkodylas
      Nick Korkodylas  4 days back

      I am constantly being called an "anti-vaxxer" and a "science denialist" just for pointing out that it's a bad idea to allow governments make sticking needles in your children mandatory. They also called me a "conspiracy theorist" for pointing out that some vaccines used mercury compounds as preservatives.

    • Jordan Sutche
      Jordan Sutche  6 days back

      The fact you brought up Wakefield's "research" just proved you didn't actually look into it at all. That's a fact.

    • Haziq Aiman
      Haziq Aiman  7 days back

      Ok gus

  • Tovarishch Vaschily
    Tovarishch Vaschily  8 minutes back

    I have never been vaccinated. And I never get sick, I do not have any mental health issues or brain diseases, my sister was the same up until she was forced to have one, not even 10 days later she contracted a very bad case of the measles, and then 4 years later was diagnosed with OCD, even though she had never shown signs of it before, she was 27 when this happened. Everyone keeps telling me "you just have a good immune system", so is it a coincidence that the majority of people who don't get vaccinated just happen to have a "good immune system", ill let you decide. Let my sisters story at least be somewhat of a weight on your scale, thank you

    • The three cool kids: Finnegan, Leo, Waverly

      I’m betting over 90 percent of the 8100 dislikes are suicidal people/anti-vaxxers

      • Enzo Luiz
        Enzo Luiz  1 hours back

        Please dont be a anti-vaxx please dont be an anti-vaxx please dont be an anti-vaxx

        • Ozzie40
          Ozzie40  4 hours back

          I'm proud to say I've never been vaccined now

          • Error Info
            Error Info  4 hours back

            Anti-vaxx moms be like: *Cheering* THEY KNOW

            • Chupa Chups
              Chupa Chups  4 hours back

              SHUT UP U ANTI VAX MAN

              • Autistic oak
                Autistic oak  6 hours back

                conclusion fucking use vaccines

                • carlos delgado
                  carlos delgado  6 hours back

                  Anti vaxxers: Hey don't use a vaccine in my child!

                  Doctor: Miss, No spawn killing

                  • Hien Nguyen
                    Hien Nguyen  10 hours back

                    Human are really stupid sometimes, flat earth, fake moon landing and now antivax

                    • Sara Will Gasha
                      Sara Will Gasha  12 hours back

                      Are they any anti vaccines who were convinced that vaccination is necessary? Interested in hearing from you.

                      • RapidHmsta 6241
                        RapidHmsta 6241  12 hours back

                        Bacteriophage: Allow me to introduce my self.

                        • dontsubscribe
                          dontsubscribe  13 hours back


                          Love being alive

                        • Abdullah Baroon
                          Abdullah Baroon  17 hours back

                          * Me talking to my freind about bieng teenagers and adult hood *
                          His anti vax mom: hahahahah YOU FOOL

                          • KerbalTube HD
                            KerbalTube HD  18 hours back

                            All vaccinated kids will die...

                            It just takes 97 years longer than antivaxx kids

                          • Big Nutty
                            Big Nutty  22 hours back

                            Even if vaccines somehow cause autism, in the perspective of a caring parent, I much prefer my child to have autism than dying of a preventable disease.

                            • ChaCha Channel
                              ChaCha Channel  22 hours back

                              Anti Vaxxers, have you considered? there is 1 person in the left and 1 million people in the right, only one of the two groups must die, which would you choose?

                              Its the same with vaccines, yes, there is a chance that it would mutate and harm a child but if you compare it to the amount of lives that it could save, you can only think of how its better to take that risk rather than endangering the lives of the masses.

                              TLDR; Vaccines may be not perfect but we accept it and its use precisely because its the closest we could get to complete safety for our lives and the lives of others.

                              • Tix is gey
                                Tix is gey  10 hours back

                                @Vary Olla the pathogen in vaccines are not supermutant, i am fully up to date in my vaccines and for 13 years i have not experience: Polio, Measeles, And Rubella. Quit your bullshit.

                              • Vary Olla
                                Vary Olla  13 hours back

                                Actually there is no mutation involved = save for perhaps by the unvaccinated who subsequently catch what we vaccinate against.  By allowing those active infections which vaccination can prevent = they are potentially allowing the rise of new mutations to occur.

                                Meanwhile if you look at serious adverse reactions to vaccines and compare them to what we see among people who catch what the vaccine prevents = we see similar symptomology.  That tells you those reactions are being driven - not by the vaccine ingredients per se - but rather from the pathogen in the vaccine which causes similar reaction in both vaccination and the disease.

                                So now understanding that the pathogen is the culprit involved in both = it becomes as you alluded to a matter of which one precipitates those severe reactions less.  History conclusively demonstrates that people suffer serious adverse reactions to vaccination at an incidence level exponentially less than what we used to see from the diseases in the time before a vaccine was employed.  That makes vaccination a better option as you are at risk regardless since infectious pathogens exist in nature = and thus in human populations. 

                                Accordingly understanding that we used to see adverse reactions to the diseases in the time before vaccines were employed = we therefore must consider the reality that those few people who could not tolerate being vaccinated using a weakened form of the pathogen would in all likelihood react similarly or worse upon exposure to the full-strength version of the same.  That means people unable to tolerate vaccination would be among those who ended up hospitalized anyways upon catching say measles in the time before the MMR.  The MMR etc. however as noted gives you better odds.  Have a nice day.

                            • PancakeBoie
                              PancakeBoie  24 hours back

                              100% of all people who have breathed oxygen in their lives have died

                            • Robert Eischen
                              Robert Eischen  1 days back

                              If you use your medical degree from the university of Google to tell me vaccines are bad, I'm not gonna listen. I prefer the opinions of people who study medicine their entire life compared to you.

                            • LewY_ HuN
                              LewY_ HuN  1 days back

                              -Karen is typing

                              • David T. Lego Animation

                                6:57 - inflammation of the genetalia...nor literally right?

                                • angelos efstratiou
                                  angelos efstratiou  1 days back

                                  Vaccines to anti-vaxxers:
                                  You are being rescued, please do not resist

                                  • skoorb nimajnib
                                    skoorb nimajnib  1 days back

                                    Are vaccines safe now? Now that they don't contain a lot of mercury and aluminium. Who knows? One maybe. But how many do they give babies in one batch? Certainly many scientists think not and many juries and judges think not. People are calling me crazy in intimidating tones. But listen, no one is paying me to write this so it comes from my heart. You vaccinate yourself and your baby.
                                    Don't be too quick to judge what is safe or not for others when it is their risk.
                                    We can't say that food has toxic chemicals so let's inject some too. Well - you can...but can you impose it on parents of a newly born baby?
                                    The idea of a vaccine is rational. And maybe it can work in some cases but so was communism justified in some senses. But you are not going to force me into saying the gulag concentration camps were good.
                                    I don't want to be abnormal...or called crazy, but listen - What we call call normality is based on a lot of appearance and the authority of paid professionals who were often just good swats and also the "common sense" of the masses who just want to eat sleep and be happy and get a quick fix to cure their ills etc. But that reality including scientific orthodoxy gets broken down. New science breaks through that with imagination and faith in a new theory, and scepticism about an old theory. Information and organization is important too but above all a passion for truth. Truth is neither absolute....but not absolutely relative either.
                                    Another caution: scientists are often just technicians. Utility is important but science must be not only concerned with plugging gaps and making money. Therefore, be suspicious of "common sense", authority, and even utility. Most of what medical science thought has now been contradicted and new science is emerging all the time to say: "hey! Wait! Prozac is not so good after all!" Etc. And indeed, maybe saffron works better! ". The utility is greater from the point of view of a patient can have more natural things and not chemicals or monkey viruses which weaken his immune system and end up in his brain giving him Alzheimer's. Of course, garlic is too cheap and wouldn't find the pharmaceutical industry but, well....also, some people worry about their breath smelling. In that case I recommend chewing gum without aspartame. In the case of seaweed, I wouldn't recommend the Pacific and in the case of war, ask your trusted new world order captain if they put radioactive material in the bullets! You don't want to go home a veteran with gulf war syndrome, do you?

                                    • Null Void
                                      Null Void  4 minutes back

                                      "science breaks through that with imagination and faith...."
                                      "therefore be suspicious of common sense, authority and even utility"

                                      u say faith.. yet u want us to be suspicious of common sense, authority and even utility. I dont think that being suspicious to those things is what I call as being faithful.

                                    • The Shinto Railfan
                                      The Shinto Railfan  1 days back

                                      Yes, vaccines are safe. The Mercury and Aluminum in them is harmless. I'm pretty sure it's in there to preserve the MMR, which is why there's more in your food than in vaccines.

                                  • Fawcett Master
                                    Fawcett Master  1 days back

                                    Y’all see
                                    Measles is powerful
                                    It got to Greenland

                                  • Καςεγ Χαος
                                    Καςεγ Χαος  2 days back

                                    Succinctly put! Consider me a true subscriber to this balanced and informative channel.

                                    • Burn Angel
                                      Burn Angel  2 days back

                                      Gotta love how Kurzgesagt wrote the title in a way antivaxxers will be drawn to watch it, just to show them how wrong they are.

                                    • ItzGrexisPvP
                                      ItzGrexisPvP  2 days back

                                      2:06 someone can make a video game about this, don't you think?

                                    • BananaDayz
                                      BananaDayz  2 days back

                                      People shouldn’t judge anti-vaxers since they may have their reasons
                                      For instance my brother got serious allergic reactions and poisoning from vaccines (Confirmed many many times) and has struggled now for over 15 years with his liver suffering from the poisoning (the rest if the side effects are more complicated). And we had to go to hundreds of doctors and he has recieved hundreds of treatments, for this reason we didn’t vax for a few years but are considering going back to vaccinating, he is doing well and is almost cured.
                                      Please don’t judge or hate with comments and replies
                                      This was just me explaining that some anti-vaxers have reasons
                                      And we shouldn’t make fun or judge people no-matter what they believe!

                                      • BananaDayz
                                        BananaDayz  7 hours back

                                        The Shinto Railfan And I just want to thank you ♥️, you are the first person i could houve had a ‘conversation’ with without being full on insulted or called dumb and inhuman. Thank you!♥️

                                      • BananaDayz
                                        BananaDayz  12 hours back

                                        The Shinto Railfan I fully agree and understand (All that i was trying to say is that people should stop calling all anti-vaxxers dumb or ‘like flat earthers’ without hearing their reasons... and we shouldn’t even call anyone dumb 🤣) and I know many people just don’t vaccinate because they are too lazy to get a vaccine or read one story from a victim and i agree that is wrong.♥️❤️♥️

                                      • The Shinto Railfan
                                        The Shinto Railfan  13 hours back

                                        No, @BananaDayz, they have no reasons. They don't want to look at the whole scientific picture. They hardly ever use something more than there gut feeling when deciding something that could be life or death to someone who can't be vaccinated, like your brother. And, for the most part, if you have an allergic reaction to MMR or any other vaccine, you should get treatment and be fine.

                                      • BananaDayz
                                        BananaDayz  18 hours back

                                        The Shinto Railfan I fully understand what you are saying and we are not gonna vax him for this reason and my situation was most likely very rare but all i was trying to say is that with some people who are anti-vax have their reasons like the video said there can be side effects even tho most can be cured, so some are not cured or some people are just scared of vaxing cause of what they heard.. and can we blame them? They just want the best for their children, and sometimes things like this confuses you and places you in a position where you don’t know what to do and you decide on a side (vax or anti-vax) and really can we blame them they just want they best for their children... but I totally agree that anti-vax protests are not necessary, but i believe people should be able to share their story (bad or good) and i thank you for not full on judging me like most others have ♥️♥️♥️

                                      • The Shinto Railfan
                                        The Shinto Railfan  1 days back

                                        Hold up.
                                        1: If your brother got a severe allergic reaction, only herd immunity can save him from injury or death. And the only way to get that is by vaccinating.
                                        2: "and has struggled now for over 15 years with his liver suffering from the poisoning"
                                        That's very, _very_ , rare. He's probably 1 of 100 in the world.
                                        3: "but are considering going back to vaccinating"
                                        That's a _horrific_ idea. Your entire situation would just repeat itself. If he's allergic, the only thing that can protect him is heard immunity, *not* vaccinating him. So it's your job to encourage people to vaccinate to protect him.
                                        4: "This was just me explaining that some anti-vaxers have reasons"
                                        All you did was talk about you 1 in 1,000,000,000 case. You did nothing else.

                                    • MochaPastelz
                                      MochaPastelz  2 days back

                                      How to stop anti-vaxxers:

                                      Call them pro-disease
                                      They hate being made fun of so if they vaccinate their kids they won't be called pro-disease anymore and finally understand

                                      There's a 50/50 chance it'll work

                                      • KritzИ
                                        KritzИ  2 days back

                                        Anti Vaxxers= F2P Player
                                        People that use Vaccines= P2P Player

                                        • M o d z z
                                          M o d z z  2 days back

                                          E y e s c a u s e t e m p o r a r y b l i n d n e s s

                                          • Kaytlin Justis
                                            Kaytlin Justis  2 days back

                                            When I first read about vaccines as a child, it was about rabies, and the vaccine is like a WARNING poster to your body. When you get a specific vaccine, it gives your body a 'heads-up' to a specific disease to prepare against. Something similar to this video. It was honestly shocking to see how far measles has rebounded because people have stopped themselves and their kids from vaccinations in this year alone! People who rely on other's vaccinations end up getting their kids sick because they are too young for the Warning posters! In a perfect world, someone would create a specific gene that makes us adapt to illnesses spontaneously, and prevent us from getting sick ever again, because our memory cells can mutate like a virus and drug-resistant bacteria.

                                            • ManProg 08
                                              ManProg 08  2 days back

                                              Non-anti vax: yeah sure we need vaccine

                                              Anti vax: (don't see this video)

                                              • Sara Martinez
                                                Sara Martinez  2 days back

                                                The antivax problem will solve Its self so yea

                                                • Anwukia
                                                  Anwukia  2 days back

                                                  me: vaccines are protective agents
                                                  anti-vaxxers: you have autistic

                                                  • Mushroom Cow
                                                    Mushroom Cow  2 days back

                                                    alright bois i have autism and my mum says that one of her friends' son has low functioning autism because he got the swine flu shot when he was 6 weeks old and my mums lowkey retarded i wanna move in with my dad becuase he has a brain (my mum knows vaccines dont cause autism but she thinks it makes vaccines more severe i cant)

                                                    • maxim
                                                      maxim  2 days back

                                                      vaccines have one side affect

                                                      IT'S CALLED ALIVE

                                                      • Malamex
                                                        Malamex  2 days back

                                                        F O R T N I T E C U A S E S A U T I S I M.

                                                      • Jason Khimera
                                                        Jason Khimera  2 days back

                                                        I know it's awful... But... Let the Antivax not vax... Then they and their kids are more likely to die and evolution takes its course...

                                                        • Karl Håkansson
                                                          Karl Håkansson  2 days back

                                                          the main goal of vaccinating is to remove a certain disease from the landmass, and preferably the entire world. This has been done several times before, for example the plague. But because of certain individuals that don't vaccinate, this can't really happen, thus causing diseases to remain. There are also people that can't vaccinate, often due to being immunocompromised, too young or too old. These people could easily die, simply because some mongoloid anti-vaxer sneezed in their faces. Vaccinations should be mandatory for everyone, except for the immunocompromised that run the risk of dying if they did vaccinate.

                                                        • Ykario
                                                          Ykario  2 days back

                                                          Nope, the kids aren't responsable for their parents retardness, and they still endanger others

                                                      • CattAnimations
                                                        CattAnimations  2 days back

                                                        Karen’s like normal hate

                                                        • Vincent Alley
                                                          Vincent Alley  2 days back

                                                          Also, so what if your kid is autistic? They are basically saying that they don't want autistic people. Anti-vaxxers are even worse than we think.

                                                          • Семён Маликов

                                                            If antivaxxers truly believe vaccines are evil, why are they vaccinated?

                                                          • Lancashirelad
                                                            Lancashirelad  2 days back

                                                            You know being autistic and hearing that parents would rather have their children die then "catch autism" makes me feel a bit disheartened if im being honest.

                                                            At the end of the day from my angle it looks like these mothers want a trophy daughter/son to brag about, why they would brag about putting their own kid in physical danger most likely as its "against the norm" therefore they will be noticed easier, some people believe that big pharma is plotting some insidious plan and thats why they dont vaccinate others just use that as a cover from the reality of the situation I feel.

                                                            • Nanybone
                                                              Nanybone  1 days back

                                                              Lancashirelad they think their child would get less serious side effects and be fine later

                                                          • Games Android
                                                            Games Android  2 days back

                                                            Dude,i did learn something Here that my School Will never teach us

                                                            • Karl Håkansson
                                                              Karl Håkansson  7 hours back

                                                              @Games Android and may I ask how old u are?

                                                            • Corey Playz
                                                              Corey Playz  1 days back

                                                              @Games Android Oh. Uh...

                                                            • Games Android
                                                              Games Android  2 days back

                                                              @Karl Håkansson i'm from Brazil Bro...

                                                            • Karl Håkansson
                                                              Karl Håkansson  2 days back

                                                              Well, I don't know what country you're from, but if you live in a civilised, developed country, you will be taught about vaccines, the dangers of not vaccinating, as well as the possible side effects, in school. Where I'm from, we talked about this about two years ago, in seventh grade, when I was thirteen.

                                                          • Why does this name
                                                            Why does this name  2 days back

                                                            Who else just came here for the anti-vaxx jokes?

                                                            • mege5876 tran
                                                              mege5876 tran  3 days back

                                                              all of those dislikes are from anti vaxxers

                                                              • Hyper_boi
                                                                Hyper_boi  2 days back

                                                                @mege5876 tran hhahaah

                                                              • mege5876 tran
                                                                mege5876 tran  2 days back

                                                                @Hyper_boi true plus im just imagining a karen before watching the video say: aha i knew it and then get super pissed after watching the entire video

                                                              • Hyper_boi
                                                                Hyper_boi  3 days back

                                                                yes only Karens

                                                            • Ketrick GD
                                                              Ketrick GD  3 days back

                                                              Kurzgesagt: makes a compelling video on vaccines

                                                              Anti-vaxx moms: I’m going to pretend I didn’t see that

                                                              • Lê Hoàng Thiện
                                                                Lê Hoàng Thiện  3 days back

                                                                Love this video!