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 • 76 245

  • 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  2 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  6 days back

      Ok gus

  • Hien Nguyen
    Hien Nguyen  3 hours back

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

    • Sara Will Gasha
      Sara Will Gasha  5 hours back

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

      • RapidHmsta 6241
        RapidHmsta 6241  5 hours back

        Bacteriophage: Allow me to introduce my self.

        • dontsubscribe
          dontsubscribe  5 hours back


          Love being alive

          • Abdullah Baroon
            Abdullah Baroon  10 hours back

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

            • KerbalTube HD
              KerbalTube HD  11 hours back

              All vaccinated kids will die...

              It just takes 97 years longer than antivaxx kids

              • Big Nutty
                Big Nutty  14 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  15 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  3 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  6 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  16 hours back

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

                  • Robert Eischen
                    Robert Eischen  19 hours 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  20 hours back

                    -Karen is typing

                    • David T. Lego Animation
                      David T. Lego Animation  21 hours back

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

                      • angelos efstratiou
                        angelos efstratiou  22 hours back

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

                        • skoorb nimajnib
                          skoorb nimajnib  24 hours 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?

                          • The Shinto Railfan
                            The Shinto Railfan  20 hours 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  1 days back

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

                          • Burn Angel
                            Burn Angel  1 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  1 days back

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

                            • BananaDayz
                              BananaDayz  1 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  3 minutes 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  5 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  6 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  11 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  20 hours 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  1 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  1 days back

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

                                • M o d z z
                                  M o d z z  1 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  1 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  1 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  22 hours 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

                                                    • Corey Playz
                                                      Corey Playz  1 days back

                                                      @Games Android Oh. Uh...

                                                    • Games Android
                                                      Games Android  1 days back

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

                                                    • Karl Håkansson
                                                      Karl Håkansson  1 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  2 days back

                                                      all of those dislikes are from anti vaxxers

                                                      • Hyper_boi
                                                        Hyper_boi  1 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  2 days back

                                                        yes only Karens

                                                    • Ketrick GD
                                                      Ketrick GD  2 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  2 days back

                                                        Love this video!

                                                        • Dylan Allen
                                                          Dylan Allen  2 days back

                                                          anti vaxxer logic: i rather swim through the poison crocodile infested river then cross the 90% safe bridge

                                                          • Maxxine DeOcampo
                                                            Maxxine DeOcampo  2 days back

                                                            I feel bad for the people who are allergic to vaccines

                                                            • The Shinto Railfan
                                                              The Shinto Railfan  2 days back

                                                              Their the reason everyone else should vaccinate! To protect them!

                                                          • Fariha Zullaina Z
                                                            Fariha Zullaina Z  2 days back

                                                            Is no one going to mention the Avengers tower and helicarrier at 4:54 ?

                                                            • skoorb nimajnib
                                                              skoorb nimajnib  2 days back

                                                              In the past vaccines had mercury and more aluminium so it is proven that at least for that reason they were poisonous. Also courts secretly pay out compensation to people for deaths, autism and so on.

                                                              • Corey Playz
                                                                Corey Playz  1 days back

                                                                Mercury= Bad And will kill you
                                                                Vaccines have little mercury in them
                                                                Vaccines = Bad and will kill you
                                                                Vaccines = Death
                                                                *_L O G I C_*

                                                              • Max Leonard
                                                                Max Leonard  2 days back

                                                                Vaccines in the past contained a non-toxic variant of mercury. it was removed to ease public opinion. Vaccines still contain about 100-150 grams of aluminum but you actually ingest more aluminum from the foods you eat in about a week. This minuscule amount of aluminum in vaccines wont harm the body in any way.

                                                            • skoorb nimajnib
                                                              skoorb nimajnib  2 days back

                                                              Skepticism is healthy. Especially when it’s about staying healthy. It’s like religion. I believe in God but I am not going to give over all my faith to a book or an institution. It’s common sense. Of medicine in the past historians say the people often got better despite the medicine or got worse because of it. But now there is also the big business aspect and the planning from the elite to reduce the population. That easier to prove from listening to Bill Gates than the veracity of his vaccines.

                                                              • Karl Håkansson
                                                                Karl Håkansson  1 days back

                                                                Business aspect? You do realise that most developed countries give out vaccinations for free, or at a minuscule cost? And what do you mean "to reduce the population"? Death caused by vaccinations are SO rare. If anyone was trying to reduce the population (no one is btw), they aren't doing a great job at it. You seem like the biggest conspiracy nut I've ever seen. Don't go around spreading false information.

                                                              • The Shinto Railfan
                                                                The Shinto Railfan  2 days back

                                                                That last part is 100% false.

                                                            • Aldrich Saint of the deep

                                                              Im not vaccinating what's gonna happen am I gonna get measles ha! Yeah right- person who got measles

                                                              • Spaghetti Noob
                                                                Spaghetti Noob  3 days back

                                                                get rekt liberals

                                                                • LoneWolf 125
                                                                  LoneWolf 125  3 days back

                                                                  Anyone else in the comments to see all the anti vaxers