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 • 80 358

  • 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.

    • New Antarctictangle/JoMiMi
      New Antarctictangle/JoMiMi  6 hours back

      You can't convince me, this is all FAKE NEWS. Vaccines cause autism, HIV, and are made from poison. They cause death as well. If you were to do the real science, you would find that there are facts to back this up, and they are a COVER-UP by the GOVERNMENT. The government puts harmful chemicals in our vaccines, leading our children to be mind-controlled by the government.

    • OfftoShambala
      OfftoShambala  1 weeks back

      K-Tech PL no I don’t want to sneeze on unvaccinated children I don’t like but I laugh at the vaccinated children when they go into seizures... that’s super funny every time... if you call the doctor, they will tell you seizures are normal... might as well have fun with that?

    • DMGamer99 DMGamer99
      DMGamer99 DMGamer99  1 months back

      *Takes anti-vaxers seriously*

    • Jaxson Presley
      Jaxson Presley  2 months back


  • Fabio Spasiano
    Fabio Spasiano  23 minutes back

    *when the intelligence detects a big infection*

    • no
      no  24 minutes back

      anti vaccine ppl should be in jail for child murder. They're trying to kill children srsly

      • The Shy Guy Studio
        The Shy Guy Studio  27 minutes back

        AntiVaxx : Let us introduce ourselves.

        • PLG-Streams TV
          PLG-Streams TV  39 minutes back

          See the video without looking at it

          Also anti-vaxers:
          I knew it

          • Luiz
            Luiz  1 hours back

            Antivaxxers (sees this video): Oh boi, finally someone smart enough to explain how vaccines are EVIL.
            Literally everyone else (Let me rephrase that, literally everyone that has a working brain): Oh boi i can't wait when he rekts these stupid antivaxxers.

            • wiemach ichdasprivat
              wiemach ichdasprivat  5 hours back

              8.53 i like how he gets a bit aggressive for a second

              • garagem81 br
                garagem81 br  5 hours back

                I'm becoming anti-vax because vaxxines cause those annoying pieces of crap called adults

                • JEBEDIAH KERMAN
                  JEBEDIAH KERMAN  6 hours back

                  I just got my flu shot 6 days ago. Better safe than sorry.

                  • voxane
                    voxane  2 hours back

                    gonna be getting mine on halloween PogU

                • OwlsWillTakeOver TM
                  OwlsWillTakeOver TM  7 hours back

                  This video needs to be spread to more people

                  • TheWiery322
                    TheWiery322  7 hours back

                    I think vaccines are a miracle, however since we get most of our vaccines from China, alot of them are being tainted. Look up polio out breaks and polio vaccines

                    • Richard Gregory
                      Richard Gregory  3 hours back

                      Polio outbreaks are associated with poio vaccines because the vaccine use dmost often is oral (given by mouth). That's cheaper and easier to do, and it is therefore highly suited for use in poor countries. It uses a live (but highly attenuated) virus. This virus can rarely be shed in the faeces of vaccinated childre, and if the sanitation system is not adequate, it can contaminate the drinking water supply. The virus can then circulate for many months among a large population, and very rarely it can mutate into a more virulent form. This can result in polio disease if the population is not vaccinated. Such "outbreaks" are almost invariably confined to poor countries with bad to non-existant sanitation, and where vaccination rates are low. These "outbreaks" are also invariably muc much smaller than the outbreaks of "wild" polio that used to occur before vaccination.

                  • normal humanZ
                    normal humanZ  8 hours back

                    Meme time

                    Glad i already vaccinated

                    • Connor
                      Connor  8 hours back

                      Karen dislikes this video

                      • Luka Stojanovic
                        Luka Stojanovic  8 hours back

                        I love how you explained it

                        • Ville Vilkki
                          Ville Vilkki  9 hours back

                          Okay this comment is kinda sick, but anyways. If we let the antivaxxers not to vaccinate their kids, we have a good naturalselector for dumbness and we can ease the case of over population in the world

                          • Ms Minny
                            Ms Minny  9 hours back

                            I havent gotten a vaccine shot in over 5 years an I've felt so much better when I stopped getting them...

                            • A A
                              A A  5 hours back

                              Placebo time

                            • JEBEDIAH KERMAN
                              JEBEDIAH KERMAN  6 hours back

                              I wouldn't test my luck. Better safe than sorry.

                          • Wład Kapelinski
                            Wład Kapelinski  9 hours back

                            I just wanted to clown on the anti-vaxxers but most of them didn't live long enough to see this video.

                            • SeedPlanter
                              SeedPlanter  12 hours back

                              PLACEBO STUDIES WHICH IS THE GOLD STANDARD FOR SAFTY TESTING IN ALL MEDICATIONS.....ISNT DONE WITH VACCINES !!!they dont care if your kid gets autism..They cant be sued! Your a fool if you trust big pharma.

                              • Sproot Overalls
                                Sproot Overalls  11 minutes back

                                it's because that's so unethical! why would you pretend to give someone a vaccine when they are ill?! that would not help them at all. also, placebo studies are pretty useless unless you seriously doubt the medicine is accomplishing the task.

                              • Richard Gregory
                                Richard Gregory  11 hours back

                                If you want to sign up to a program where they test a vaccine against let's say ebola or rabies where you might get the placebo then you go right ahead. Only there are no such programs, because they are unethical to the point of being illegal. You're cluelessly asking for something you have no understanding of. A placebo study would mean taking a group of patients, randomly injecting them with either the vaccine or a placebo (and neither they nor the person giving the injections would know which was which). Then to avoid random factors (like some patients avoiding infection simply by never encountering the disease), you'd have to deliberately inject them with the disease the vaccine is supposed to prevent and wait to see who gets sick and who doesn't. Now, considering we're talking about some really nasty stuff here, do you think it;s ethical to deliberately try to infect people with something like polio, tuberculosis, typhus, cholera, smallpox, rabies or ebola to test the vaccine? As I said, if you want to I seem to recall that the Nazis actually did this sort of stuff in their deathcamps though. Deliberately infected people with often deadly diseases to see if vaccines or drug treaments worked or not.

                            • When you can’t change your profile pic

                              Anti-vax people: *doesn’t vaccinate their kids*
                              Me: meh
                              Anti-vax people: *doesn’t vaccinate their pets*
                              Me: you have crossed the line buddy

                              • Memelordo420
                                Memelordo420  13 hours back

                                Here's a side effect of vaccines....
                                It spawns anti-vaxxers

                                • Lorens Rewolle
                                  Lorens Rewolle  13 hours back

                                  why was the example of the parallel world based on the avengers

                                  • Ying Yang
                                    Ying Yang  13 hours back

                                    According the CDC, measles had a mortality rate of 0.0001% in the US the year before the vaccine was introduced

                                    • Richard Gregory
                                      Richard Gregory  11 hours back

                                      0.01% actually. Doesn;t sound much, but measles outbreaks were on average 3-4 million a year, and resulted in 48,000 hospitalisations from serious complications, and 1,000 cases of encephalitis where the virus spread to the brain and causes swelling, and half of these patients died. So in an average year, 500 preventable deaths. There was not and there is not any cure for measles. All you can do is provide supportive care like fluids, and antibiotics to prevent secondary infections which set in because measles severely weakens the body..and then hope the immune system prevails. In fact even in healthy people who make a full recovery after a mild measles infection remain vulnerable for many months, because fighting the virus depletes the immune system of it's resources and it takes a long time for it to recover to full strength. In this time you are much more liable to catch other diseases, and they will be more severe if you do.

                                  • Lorens Rewolle
                                    Lorens Rewolle  13 hours back

                                    yes vaccines are very dangerous so use them on your pets but not on your children according to some dumbass

                                    • doodle poodle
                                      doodle poodle  13 hours back

                                      I've had pneumonia as a baby and again as a teen, then a third time as an adult, I dunno y I'm so prone to it

                                      • SpyNix07
                                        SpyNix07  14 hours back

                                        Anti-Vaxxers: VaCcIeNs CaUsE aUtIsM aNd DeAtH, ChEcK mAtE gOvErNmEnT!!!

                                        Actual research: 3:45

                                        (Only a man or woman of culture will get this.)

                                        • Noah Marsden
                                          Noah Marsden  15 hours back

                                          My parents are anti-vaxxers, and I've asked them countless times why they chose not to vaccinate and they always seemed to have various reasons. I suffered from measles at a very young age, and thankfully I lived to tell the tale. I intend to get vaccinated as soon as possible and to vaccinate my kids. Videos like these really do help. Especially growing up in an environment where vaccines were a taboo subject. Thank you Kurzgesagt.

                                          • Ying Yang
                                            Ying Yang  11 hours back

                                            @Richard Gregory 4million cases, 400 deaths

                                          • Richard Gregory
                                            Richard Gregory  11 hours back

                                            @Ying Yang 0.01%, 500 deaths in average years, with 48,000 people so sick from complications, they had to be hospitalised

                                          • Ying Yang
                                            Ying Yang  13 hours back

                                            "thankfully I lived to tell the tale" - measles had a mortality rates of 0.0001% in the US the year before the vaccine was introduced

                                        • Pokerface
                                          Pokerface  15 hours back

                                          Karen uses this video as her banner

                                          • Key Harvey
                                            Key Harvey  15 hours back

                                            I'm pro vaccination but I'm terrified of shots and getting blood drawn and needles in general

                                            • big lancer
                                              big lancer  14 hours back

                                              I used to be the same (yes im young so that means my mom is pro-vax and belives the power like me) so I use the thought of how bad the infection is at the time im getting the shot

                                          • cherry i guess
                                            cherry i guess  15 hours back

                                            vaccines cause adults

                                            • chill man
                                              chill man  16 hours back

                                              Karen’s after watching this video: aight ima head out

                                              • BLOOD WOLF
                                                BLOOD WOLF  16 hours back

                                                Should have brought up that case in Mexico with all the female children going into seizures from the HPV vaccine (InfoWars covered and pointed at that case repeatedly) and if getting vaccinated every year for the flu which contains Aluminium, Formaldehyde, and Thermisole eventually builds up in the body or not? Those are some arguments I hear a lot. (I was military and am vaccinated against everything, my animals get vaccinated, etc so just chill everybody I'm bringing up some more specific arguments out there)

                                                • Richard Gregory
                                                  Richard Gregory  11 hours back

                                                  "All" female children? InfoWars? Really? They don;t use Thimerosal any more, you get more aluminium in one day's worth of normal food than a lifetime of vaccines, and your own blood - right now - has a higher concentration of formaldehyde in it than is found in any vaccine, because your own body makes formaldehyde as an essential part of it's metabolic processes lol

                                                • Pugsamurai
                                                  Pugsamurai  15 hours back

                                                  The feck are u talking lad? Anti vaxxer spreading more bullshit. InfoWars is the highest level of bullshit on the internet!

                                              • DRSReaper275
                                                DRSReaper275  18 hours back

                                                Since Kurzgesagt said all the birds have real owners,I don’t wanna let him use my own doodle bird in a video because he might kill it.

                                                • nitedumb isgreat
                                                  nitedumb isgreat  18 hours back

                                                  Just live lol

                                                  • Kate DeGonia
                                                    Kate DeGonia  18 hours back

                                                    I am not fully vaccinated against Tdap because I had a near anaphylactic reaction to the first one in the series. I still vaccinate the shit out of my children! I am vaccinated against everything else besides Tdap because I had good parents!

                                                    • Galvin Chen
                                                      Galvin Chen  19 hours back

                                                      For the people wanting to roast anti-vaxxers I'm here for yall,

                                                      I mildly dislike the sting of getting a vaccine shot so i wont get it

                                                      • Gustavo Hopkins
                                                        Gustavo Hopkins  23 hours back

                                                        I do wanna see studies about vaccines and their impact on gut bacteria. We know gut bacteria impacts development in kids

                                                        • Corey Playz
                                                          Corey Playz  21 hours back

                                                          @Gustavo Hopkins Oh. Sorry.

                                                        • Gustavo Hopkins
                                                          Gustavo Hopkins  21 hours back

                                                          @Corey Playz I dont think vaccines cause autism. I do believe destruction or a change in what type of bacteria we have causes autism and other mental and physical problems

                                                        • Gustavo Hopkins
                                                          Gustavo Hopkins  21 hours back

                                                          @Corey Playz that study has never been done...... that's what I was saying initially. We need more studies into the effects on gut bacteria from vaccines

                                                        • Corey Playz
                                                          Corey Playz  21 hours back

                                                          @Gustavo Hopkins Yes, they do, but the study that claimed that vaccines causes autism because of gut bacteria is wrong, and has been proven wrong ALOT of times.

                                                      • MinecraftTerrariaBrawlstarsFortnite 10

                                                        i will have a puncture at my shool in two weeks....
                                                        MAYBE I WILL JUST LEAVE THE SHOOL FOR A MONTH.........

                                                        • fuba
                                                          fuba  1 days back


                                                      • Luna Cookie
                                                        Luna Cookie  1 days back

                                                        The only time vaccines dont work are when you are allergic

                                                      • Juan Agua
                                                        Juan Agua  1 days back


                                                        • LiquidLama !
                                                          LiquidLama !  1 days back

                                                          1:53 the memory cell looks like the avatar

                                                          • Døøfus
                                                            Døøfus  1 days back

                                                            How much did Karen pay this channel video

                                                            • Rip
                                                              Rip  1 days back

                                                              Nothing. This video taught you that you should watch the entire video to get good contents at the end.

                                                          • sans the comic.
                                                            sans the comic.  1 days back

                                                            every anti-vaxxer ever: vaccines are poison
                                                            *watches this video*

                                                            _autistic screeching_

                                                            • Lucien
                                                              Lucien  24 hours back

                                                              Oh no, you are vaccinated... jk fuck antivaxxers.

                                                          • DabMasterGaming
                                                            DabMasterGaming  1 days back

                                                            Me: Starts anti vaxx club

                                                            Also me: Sneezes on all of the members

                                                            • fuba
                                                              fuba  1 days back

                                                              Just let them its just
                                                              *N A T U R A L*
                                                              *S E L E C T I O N*

                                                          • Maxi the Guy
                                                            Maxi the Guy  1 days back

                                                            My school has vaccines.

                                                            Im too glad i already did 3 vaccines only instead of 3000 xd

                                                            • Adrian Leon
                                                              Adrian Leon  2 days back

                                                              Karin : breaks down the door with a deep manly voice : my boy your not getting vaccinated anymore the child : dies.😱 karin noooooo with the deep voice my babi boey 😭😭😭😭😭😭

                                                              • Corey Playz
                                                                Corey Playz  22 hours back

                                                                @Adrian Leon I'm so confused...

                                                              • Adrian Leon
                                                                Adrian Leon  23 hours back

                                                                @fuba I know right

                                                              • fuba
                                                                fuba  1 days back

                                                                Thats really hard to read! xD


                                                            • FreezingHot
                                                              FreezingHot  2 days back

                                                              we learned how vaccines work in god damn elementary school. I was 8 years old when I learned how vaccines are useful to our immune system to develop and protect aganist further diseases. so my question is this : HOW CAN SOME PEOPLE BE SO STUPID?!

                                                              • TheGameFlinger
                                                                TheGameFlinger  2 days back

                                                                Who else is going to send this video to Karen?

                                                              • 冯浩
                                                                冯浩  2 days back


                                                                • 冯浩
                                                                  冯浩  16 hours back

                                                                  @Corey Playz Yeah,I have been learning English for several years

                                                                • Corey Playz
                                                                  Corey Playz  18 hours back

                                                                  @冯浩 You speak English?

                                                                • 冯浩
                                                                  冯浩  19 hours back

                                                                  @Corey Playz say it

                                                                • 冯浩
                                                                  冯浩  19 hours back

                                                                  @fuba it's true,you can google this

                                                                • Corey Playz
                                                                  Corey Playz  22 hours back