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 • 64 381

  • 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.

    • Jarley
      Jarley  6 days back

      Kurzgesagt – In a Nutshell you forgot one thing that vaccines cause:

      adult hood
      I don’t want that happening to my children

    • GodmanBG
      GodmanBG  6 days back

      It would be nice if you had touched upon, or at least mentioned that we vaccinate against a multitude of other diseases besides measles.

    • Austin Yang
      Austin Yang  6 days back

      Kurzgesagt – In a Nutshell The only person to actually have sources in the entire comment section.

    • BrettC11B
      BrettC11B  6 days back

      +Rox Paid people or bots, the lot of these post aren't even real people. 0 subs.

  • yevi Coulson
    yevi Coulson  2 minutes back

    when talking about the theoretical experiment with unvaccinated kids words like "will" implying certainty was used when talking about the negative side effects. But in the theoretical experiment with vaccinated kids words like "might" implying there is a small chance was used when talking about the negative side effects. Yes, there is a small chance but implying there is a small chance to the small chance doesn't seem right like if a statistic was to say 9 out of 10 of you will grow a beard by the age of 21 but pizza lowers the chance to 1 out of 10 grew a beard by age 21 and for me to be doing a theoretical experiment out of 100peoplke what he said would be the equivalent of me saying 90 people would've grown a beard by age 21 without pizza but with pizza only 10 people might've grown a beard by age 21. you cant Imply probability in one case and certainty in another I'm not against vaccinations I think they're fascinating and necessary to the growth of our planet but I can sense a bias in your diction

    • joan bohorquez
      joan bohorquez  8 minutes back

      I love you so much guys, your videos are soooooo great and spread accurate information. I wish to graduate soon as a chemist not only to help in the development and studies to medicine. Also to contribute with channels... with people like you, haha yeah! 🙄 i mean donating cause is not only the information is the way that you make dense themes like this in something that anyone can understand and can read and appropriate the sources.


      • morrisseyroo
        morrisseyroo  9 minutes back

        Plague enthusiasts deserve any crappy treatment they get and more.

        • lilbites games
          lilbites games  14 minutes back

          0:25 the bird in the bottom right tic tak toe game is inpossable

          • Night Shark 115
            Night Shark 115  15 minutes back

            Real talk how the fuck has the human immune system not been made into a video game.

            • Hidden Aspects
              Hidden Aspects  26 minutes back

              more deaths occur from vaccine injury than measles. what are you all afraid of? conditioned much?

              • Nick Perozzo
                Nick Perozzo  10 minutes back

                Can we have a source on that?

              • eeeaten
                eeeaten  15 minutes back

                smallpox kills less people than vaccines do. want to know why?

            • DecentAtNothing
              DecentAtNothing  29 minutes back

              If the beginning was a game I would buy it no matter what cost

              • Seal Sniper
                Seal Sniper  29 minutes back

                Me: * sees title *
                Also me: Okay, I'll bite.
                Video: * isn't promoting anti-vax *
                Me: Finally, Something that applies to everyone who didn't buy the Dyson sphere poster (i haven't framed it yet)

                • Soren Johanson
                  Soren Johanson  31 minutes back

                  PRO VACCINES FOR LIFE

                  • Jack
                    Jack  34 minutes back

                    I decided not to take a vaccine for Seasonal flu
                    *by far the worst decision ever*

                    • 제조장
                      제조장  38 minutes back

                      반백신 운동 하는놈들만 모여사는 섬을 하나 만들어서 죄다 자연도태되게 만들어야 함 온갓 질병걸려서 지들끼리 알아서 죽어야 정신차리지

                      • IcedTea God
                        IcedTea God  45 minutes back

                        Anti vaxx mom: *Clicks in the clickbait video*
                        Kurzgesagt: I pulled a little sneaky on ya

                        • Scrumble Bump
                          Scrumble Bump  45 minutes back

                          This was a great video! I love your art style!

                          • IcedTea God
                            IcedTea God  52 minutes back

                            Anti vaxx mom : I dont need vaccines I GOT VICZ VAPO RUB

                            • eeeaten
                              eeeaten  30 minutes back

                              vicks is owned by big farma! only rub you children with sticks and pray to jayyzuss.

                          • Death Beat
                            Death Beat  53 minutes back


                            • CJ Jensen
                              CJ Jensen  54 minutes back

                              measles.... in the 50's and 60's... docs said,, no problem... the cases were already down and then the vaccine comes out.... hhhmm....No deaths in USA for 10 family member got measles shot.... diabetes is Known adverse reaction on the PACKAGE insert... (you ever read one??? )...NO family hx, skinny,, no fast food access..... Eat a food, get reaction... doc says "don't eat"... take a med,, reaction... doc says..."don't take"... get a vaccine.... reaction.... doc says "just a coincidence".... do some research.....

                            • AngelLestat2
                              AngelLestat2  56 minutes back

                              Another great work of this channel.

                              • mboss
                                mboss  1 hours back

                                Karen was wrong.

                                • hen ko
                                  hen ko  1 hours back

                                  a rumbling off in the distance "feelings are often immune to facts" his job done, ben shapiro blasts off to help others in need

                                  • Hayden Kabat
                                    Hayden Kabat  1 hours back

                                    Yay I'm going to not vaccinate myself what could even..............

                                    • Andrew
                                      Andrew  1 hours back

                                      Kurzgesagt, obtaining the infinity stones to snap away antivaxxers.

                                      • extradeppresingmemes
                                        extradeppresingmemes  2 hours back

                                        the only side effect of vaccines is adulthood

                                        • Garry Summer
                                          Garry Summer  2 hours back

                                          "contrary to popular belief what doesn't kill you doesn't actually make you stronger" goes on to explain how your immune system creates memory cells that make you stronger by not having you get sick over the same virus.

                                          • GRAY XD
                                            GRAY XD  2 hours back

                                            Did you check denvaxia in the Philippines

                                            • eeeaten
                                              eeeaten  32 minutes back

                                              +Some Random Guy the problem with dengvaxia is that it works for one strain, but when you get infected with another one your body can't handle it. it's fine if you've had denge before, then get vaccinated. it's not a fault of the healthcare system, just shows how nasty dengue is.

                                            • Some Random Guy
                                              Some Random Guy  42 minutes back

                                              Yew, dengvaxia was dangerous I suppose. But that doesn't give reson to blame all the vaccines. It's like a teaxher blaming the whole class for something only one person did. And, also, because Philippine healthcare research is trash. Even though I am a filipino, i will still admit it.

                                            • eeeaten
                                              eeeaten  2 hours back

                                              did you check more than the headline on an antivax clickbait website?

                                          • Blackberry0Pie
                                            Blackberry0Pie  2 hours back

                                            It would be beneficial to a small minority of babies to stagger the immunization over a several week period instead of having multiple overly stressing the immune system simultaneously. This is educated conjecture because this type of situation cannot be ethically scientifically tested in humans. If one views vaccines as a drug with side effects, it becomes clear that taking lots of them simultaneously could cause complications, especially if the patient is unlucky enough to get an actual illness at the same time. According to CDC there are 5 vaccines(RV, DTaP, Hib, PCV13, IPV) scheduled for 2 months, and again at 4 months old, 1 of which(DTaP) contains 3 diseases in the single vaccine. Meaning at those times(2 and 4 months) an immunized baby is learning 7 immunities at the same time. The main problem with the idea of staggering the immunizations is that people are likely too busy, forgetful, or lazy to properly execute what should in my opinion be standardized vaccination procedures.

                                            • Blackberry0Pie
                                              Blackberry0Pie  8 minutes back

                                              +eeeaten Yes, but that risk is quite small. And if the spacing is relatively short(say, a week), the vaccinations would still fall within the CDC window(or quite close to it). I'm also not sold on the stabilizers being as harmless as stated, but I have not put in the due diligence to actually look at the studies because I do not have plans for children in the near future.

                                            • eeeaten
                                              eeeaten  35 minutes back

                                              +Blackberry0Pie ok. my view is that children are exposed to a great deal of antigens and a couple more are no big deal for their immune systems to handle. the number of antigens in modern vaccines is a fraction of what we used to give them. the big danger is that by encouraging vaccines to be spaced out is that we increase the window of opportunity for infection.

                                            • Blackberry0Pie
                                              Blackberry0Pie  48 minutes back

                                              +eeeaten They most likely do know that staggering is a bad idea due to people not being reliable. That doesn't mean the hypothetical isn't interesting to explore. The more interesting topic that I was hoping to bring attention to is that the multivariate systems of examining the effects of multiple drugs/diseases that are simultaneously present is a somewhat new area of study.

                                            • eeeaten
                                              eeeaten  2 hours back

                                              so giving the vaccines at the same time is more practical than staggering them (because the population are not reliable enough to get them all at the right time), therefore more effective. you don't think medical scientists know this?

                                          • Linebeck, The Persona Cuck

                                            Diseases to unvaxxed kid: My name is Inigo Mumpstoya. You killed your brother. Prepare to die.

                                            • Stanley Henry
                                              Stanley Henry  2 hours back

                                              Great video, I think you are totally right in that we need to take Anti-Vaxxers concerns seriously and help them find answers to their concerns. Making fun of them or ignoring them is how we got to where we are. Well done team.

                                              • A. Grave Mistake
                                                A. Grave Mistake  2 hours back

                                                Y'all using scientific arguments against people who don't trust arguments. Might as well argue with a pool by throwing bricks of sodium into it

                                                • GaChas siNd guT
                                                  GaChas siNd guT  2 hours back

                                                  Only anti vaxxers would watch this

                                                  • mlp_Firewind
                                                    mlp_Firewind  3 hours back

                                                    My problem with the pro vax movement is that while there are good people trying to educate people on things they simply don’t understand. it’s just a bunch of people using it as an excuse to be rude to people who are simply less educated then them which will never be excepted behavior.

                                                    • Martin But Better
                                                      Martin But Better  32 minutes back

                                                      Is it bad to be mad at a person who wants their children to die?

                                                    • eeeaten
                                                      eeeaten  2 hours back

                                                      let me get this straight. you have a problem that people who do understand are trying to educate people who don't? hmmm

                                                  • Gustoscustoms gaming
                                                    Gustoscustoms gaming  3 hours back

                                                    1:52 fortunate son starts playing

                                                    • markspencer171
                                                      markspencer171  3 hours back

                                                      A Vaccine is a weakened form of a microbe, it’s toxins or one of its surface proteins. They are made from such things as mercury, aluminum, formaldehyde, ammonium, antibiotics, MSG, or fetal calf/bovine serum.

                                                      You cannot sterilise the body, you cannot sterilise society.

                                                      Children (like centuries before) have to naturally grow immunity these things.

                                                      Vaccinations themselves have caused many deaths and medical emergencies like seizures and severe long term illness. They ultimately break down our ability to fight disease because they breakdown immunity in society. They do the exact opposite of what they claim to.

                                                      Sure they may temporarily remove one disease from a society but pretty soon something else comes along. That’s because vaccinations are leading to disease/cell mutations in humans and animals creating higher resistant strains that no amount of vaccinations will be able to stop. Pharmaceutical companies don’t care about playing with Mother nature because of billion dollar profits.

                                                      The notion that we need to use drugs to replace a societies own ability to build up immunity (as we have done for centuries) is dangerous. Drug companies want it this way cause they are making billions from it. What's to say vaccinations don’t cause disease. You would never know and Pharmaceutical companies would never want you to.

                                                      It's just another version of the big temporary band-aid fix mentality that the whole medical industry profits from.

                                                      To ban child from schooling because a parent does not want to them take drugs is straight up fascism.

                                                      • Martin But Better
                                                        Martin But Better  31 minutes back

                                                        Vaccines save lives you fucking 40 year old soccer karen
                                                        I guess you want everyone else to die

                                                      • lyrehc the bran man
                                                        lyrehc the bran man  1 hours back

                                                        +markspencer171 if you're for real, you deserve to lose any degree tied to that if you're out here spouting this bullshit

                                                      • eeeaten
                                                        eeeaten  1 hours back

                                                        +markspencer171 i'm certainly not a microbiologist like you, i'm an actual scientist who reads and understand science.
                                                        you know what causes seizures, deaths and longterm illness? measles. you're endangering kids. that's who you are now.

                                                      • markspencer171
                                                        markspencer171  2 hours back

                                                        +eeeaten How do you know ? Are you a microbiologist like me ? Nope....

                                                    • Synonymous
                                                      Synonymous  3 hours back

                                                      "But muhh deep state!!" They screamed.

                                                      • Cabruh
                                                        Cabruh  3 hours back

                                                        F for that kid who died from measles

                                                        • TheaDragonSpirit
                                                          TheaDragonSpirit  3 hours back

                                                          Anything that puts a disease in someone increases the risk of DNA damage, which increases the chance of Autism in kids. So it might not be a coincidence that some kids get a vaccine and then have Autism. The same can happen if a kid gets any disease, so I guess it depends how lucky the kid is.

                                                          Also heard immunity is mostly nonsense. A lot of young kids are able to get a lot of diseases and yet those disease are not passed on. Why? Because when kids are ill they generally stay home around adults which are immune, and so this doesn't get passed on. If you get a vaccine it's to protect yourself, it's not going to protect everyone else too.

                                                          However I think that vaccines do more good, than they do harm. The benefits to most people out weigh the negatives. But I still think people should research each vaccine and the risks as best they can, and not just accept peoples word for it. Learn as much as they can about vaccines before they let their kids have them. I think it's naive to just accept authority and not do research when it comes to ones health, and your kids health.

                                                          • TheaDragonSpirit
                                                            TheaDragonSpirit  30 minutes back

                                                            +eeeaten Any disease a child gets can lead to autism, so getting a weak strain could cause autism. But so could any disease. Diseases cause DNA damage and that can trigger autism. A parent should give a child food that boosts the immune system to help prevent DNA damage. So technically yes a Vaccine could cause autism, but a disease could cause death or autism. Which is the worse risk?

                                                            Herd Immunity is mostly nonsense. Watch the video again, all the people round them were immune, then how did they get the disease? Think about it. Was it magic? Point being herd immunity is mostly nonsense to prevent people complaining about how vaccines didn't work for them, so that people still get vaccines because for most people they work. There is so many ways to get diseases that humans being vaccinated doesn't stop others that aren't vaccinated from getting it even if 99% are vaccinated, the only way to prevent disease spread to these people is pretty much quarantine.

                                                            The reality is factory farming is more likely to spread diseases and eating animal products spreads disease, and working in unhygienic environments spreads diseases, but no one wants to stop eating animal products. Even though meat has high amounts of pathogens. Yet no one says stop eating meat for herd immunity. Do they? Because the reality is there is so many ways to spread diseases that they think it's pointless, but actually people not having meat in their house would do more for disease prevent for those that can't get vaccinated then most people being vaccinated, because most people when ill stay away from people, but people take and cook animal products all over the place spreading diseases, because it's near impossible to get rid of the germs and pathogens caused by cutting up raw meat. So that is that. Yet people will not change. Even though it would mean more herd immunity. So the reason I say herd immunity if nonsense is because humans are spreading pathogens all over the place.

                                                          • eeeaten
                                                            eeeaten  2 hours back

                                                            "Anything that puts a disease in someone increases the risk of DNA damage" - i guess you don't want measles then - better get vaccinated!
                                                            herd immunity works, vaccines don't cause autism, and the risks of vaccination are tiny compared to the risk of harm from the diseases they prevent.

                                                        • MageInWhite
                                                          MageInWhite  3 hours back

                                                          Bruh you anti-vaxxers just got utterly roasted by kurzgesagt

                                                          How does it feel?

                                                          • EricCartman29
                                                            EricCartman29  3 hours back

                                                            Bravo Kurzgesagt

                                                            • Sharpnova
                                                              Sharpnova  4 hours back

                                                              *a rumbling off in the distance*

                                                              "feelings are often immune to facts"

                                                              *his job done, ben shapiro blasts off to help others in need*

                                                              • Kewlosh
                                                                Kewlosh  4 hours back

                                                                I got inflammation of the... “tackle box” region

                                                              • King Codex
                                                                King Codex  4 hours back

                                                                Guys here a *MAJOR* fact: if you try to disprove someone's ideas, they are more likely to believe in said ideas. Also it activate the part of the brain which deals with pain so that doesnt help😔🤦

                                                                • JP Abah
                                                                  JP Abah  4 hours back

                                                                  Kurzgesagt: Feelings don't care about your facts. Ha!

                                                                  • Thentacle
                                                                    Thentacle  4 hours back

                                                                    Yes, don't kill children! Outlaw abortions and get vaccines to the vaccinated!

                                                                    • Thentacle
                                                                      Thentacle  3 hours back

                                                                      +Psychodelic I applaud you, sir.

                                                                    • Psychodelic
                                                                      Psychodelic  3 hours back

                                                                      Thentacle I killed my children how do you feel about that

                                                                  • Juan Luchas Molinegra :V

                                                                    Vaccines are cancer, DONT USE THEM!!! ;).

                                                                    • Martin But Better
                                                                      Martin But Better  27 minutes back

                                                                      Is this a fucking joke? Because I hope so, if not, I hate to say it but you're never going to rest in "peace"
                                                                      Instead you will be thrown into hell because you killed your kids

                                                                    • Some Random Guy
                                                                      Some Random Guy  39 minutes back

                                                                      *DiD yOu GuYs KnOw? YoU cAn DrOwN fRoM wAtEr! StOp DrInKiNg WaTeR tO pReVeNt DrOwNiNg!*

                                                                    • Pho Ehr
                                                                      Pho Ehr  47 minutes back

                                                                      +Juan Luchas Molinegra :V Sources? I'm intrigued to dive deep into this argument.

                                                                    • ЯoИИiЁ MoЯЯisoИ
                                                                      ЯoИИiЁ MoЯЯisoИ  49 minutes back

                                                                      +Juan Luchas Molinegra :V you are the child that came from a broken condom, get a life

                                                                    • kuhan kannth 2.0
                                                                      kuhan kannth 2.0  2 hours back

                                                                      +Dunno What to put here how about you give us some proof that vaccines cause cancer

                                                                  • mikel dowd
                                                                    mikel dowd  4 hours back

                                                                    Why didn’t you talk about autism sources?

                                                                    • Martin But Better
                                                                      Martin But Better  26 minutes back

                                                                      Vaccines don't cause autism.

                                                                    • eeeaten
                                                                      eeeaten  4 hours back

                                                                      because vaccines don't cause autism?

                                                                    • Dazeddiagram 821
                                                                      Dazeddiagram 821  4 hours back

                                                                      mikel dowd because the person who made that claim has been debunked thousands of times please stop saying vaccines are connect to autism autism is genetic if you had taken high school biology you would know this

                                                                  • Louis Nick .I
                                                                    Louis Nick .I  4 hours back

                                                                    This probably your best video till date

                                                                    • Fernando Romero
                                                                      Fernando Romero  4 hours back

                                                                      3:53 the moment anti-vaxxers have been waiting for

                                                                      • Koby Robs
                                                                        Koby Robs  5 hours back

                                                                        I can only warn about vaccines. Dont try this and make the same mistakes. I took about 6 years ago a vaccine through my arm. My friend told me to try it once in an alley. He said id feel healthy immediately. It took me years to come off of that stuff

                                                                        • vino aja
                                                                          vino aja  29 minutes back

                                                                          * in the dark alley *"hey you got the stuff ?" , "Yeah what you want ?" "I need some of that measles vaccine you know ?" " Gotchu fam"

                                                                        • eeeaten
                                                                          eeeaten  2 hours back

                                                                          +Psychodelic indeed, another lame joke. amazing.

                                                                        • Psychodelic
                                                                          Psychodelic  3 hours back

                                                                          eeeaten he’s talking about heroin dumbass

                                                                        • eeeaten
                                                                          eeeaten  4 hours back

                                                                          the risks of vaccination are tiny compared to the risks form the diseases they prevent