Why you can't compare Covid-19 vaccines

添加 2021年03月20日
What a vaccine's "efficacy rate" actually means.

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In the US, the first two available Covid-19 vaccines were the ones from Pfizer/BioNTech and Moderna. Both vaccines have very high "efficacy rates," of around 95%. But the third vaccine introduced in the US, from Johnson & Johnson, has a considerably lower efficacy rate: just 66%.

Look at those numbers next to each other, and it's natural to conclude that one of them is considerably worse. Why settle for 66% when you can have 95%? But that isn't the right way to understand a vaccine's efficacy rate, or even to understand what a vaccine does. And public health experts say that if you really want to know which vaccine is the best one, efficacy isn't actually the most important number at all.

Further reading from Vox:

Why comparing Covid-19 vaccine efficacy numbers can be misleading: www.vox.com/22311625/covid-19...

The vaccine metric that matters more than efficacy: www.vox.com/22273502/covid-va...

The limits of what vaccine efficacy numbers can tell us: www.vox.com/21575420/oxford-m...

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  • It is just the same poison only with different names on them!

  • Can't believe there are still ppl around saying that covid ain't a thing -_-

  • This sadly did not age well. Especially the last quote.

  • But still Moderna and Pfizer are better than other vaccines.

  • Now pfzer recognise more infection because of hard to pronounce pfzer brings a new contagion

  • Not a problem for me, 'cause I'm not getting ANY of them! LOL!

  • !!!

  • The truthful hammer scilly bore because euphonium baly bake against a harsh berry. ripe, steep mountain

  • yea yea sure, then this woman who reads the news, let me ask you will you take pfizer or jj?

  • "Why you can't compare Covid-19 vaccines" I can- all of them have spike proteins which is what the virus needs to replicate.

    • You good bro? Do you need to watch a vid on how MRNA vaccines work or were you high when you typed that comment?

  • all nice and dandy... except it seems to be factually inaccurate

    • So basically what you said was NU UH

  • 🤣🤣🤣🤣🤣🤦‍♂️

  • only problem with this vaccine is the governments, cdc, who information which is given. Masks prevent spread, Masks don't prevent spread, I lied when I said masks don't prevent spread. you need a mask even when vaxxed, you don't need one. you can be a carrier when vaxxed, you can't be a carrier. majority of people are not scientists, and most don't know how to find science papers or where to find them, or even understand them if they do find them. too much misinformation spread between bad actors and people who only speculate. give clear facts and lay it out so everyone can understand it clearly so they can make an informed decision. its no good sending letters and making phone calls forcing it on people.


  • J&J is better than nothing at all

  • i thought they purposely give covid virus to the people in trials after the shot

  • Why no one is talking about potential long-term side effects 🤔

  • if the efficacy is too low, you just give the virus more chance to have a mutation, into a new variant. and this will resume the story of pandemic.

    • Not if enough people are vaccinated to make herd immunity happen.

  • Welcome to the politic games of vaccines companies!!!

  • Sir cansino bio vaccine China W H O approved or not???

  • Excellent. Very informative

  • *I wish we could play this video NON-STOP 24x7 in every major Hospital, Airport, Univ, College almost everywhere within US* .

  • We need to educate people about vaccination. Even my parents refused to be vaccinated with Johnson & Johnson because of its "efficacy rate"

  • I had J&J today.

  • People ask about long term effects of the new vaccines. Media and government: it works great against C19!! See the disconnect??

  • This video should be on the television as a PSA during every single commercial break!!!!

  • Lol the mayor had no choice. Either he accepts it or gets replaced. As of now they say you need a boost for the existing vaccine lol what does that say? The vaccines are ineffective. Why are the vaccines working for 6-8 months only? These vaccines are dangerous as is the virus. Other vaccines take years to develop but these vaccines magically were approved 🤷🏽‍♂️

  • Quite frankly 99,99% of everybody would stay healthy even without the vaccines. Vaccines are for the old and week. No need to force vaccines on the young and healthy, which arguably has an extremely low risk of severe covid symptoms.

  • Compare efficacy rates 90-120 days out= >10-0% immunity? Compare results in the nation that vaccinated so well- Israel. That was in February, now they are surging. Indonesia's health system mandated vaccination for all health workers in January-February. Such a great idea we're going to do that here?! In the past two weeks, they have lost over 1.000 health workers including over 400 doctors all have died from SARS-COV2 infections. Big Pharma/CDC stop lying and let's improve the vaccines! Back to work!

  • Does that mean the J&J is better than the other ones? Since it had more exposure to different areas?

  • very useful, thank you

  • Stay safe, follow sops and believe in science.

  • I don’t understand why this is such a scary thing for people, just get the vaccine. If you can’t because of certain circumstances encourage others so you encourage others so there’s here immunity.

  • who needs vaccines just rely on your natural immunity to protect you ! yeah tell that to everyone who died

  • So....Pfizer is the best?

  • Thank you for teaching us these! Now I understand it better❤

  • is this some kind of advocacy for J&J who for many years sold cancers baby powder?

  • I learn something every time I watch this channel.

  • covid ninteen hs diaster in world

  • Public health tyranny

  • Coronavac?

  • Well explained!👍👍👍👍👍

  • Müller Cili hol vagy????

  • This is false though, the vaccines have different success rates in preventing death and keeping people out of the hospital. You absolutely can compare them. The odds that each one is identically effective is basically impossible

  • Still, the mRNA ones offer double the protection against Delta compared to the others

  • chinese flu dominate the world lols

  • The reality is that the best protection is probably taking some combination of these vaccines several weeks apart. Everyone on a single track from one company is increasingly vulnerable over time. Only a month between injections is also a mistake it seems. We need to adjust our vaccine strategy, it's not going to work the way we're currently doing it.

  • Sorry disagree. I don't want to get sick as I'm self employed and don't get sick days. If I'm going to bother to get something injected then I want the best, the one that prevents illness for the longest period. I don't think in terms of collective good, I think in terms of individual good. I want the best for me.

  • my school is using this to explain the vaccine to us but neither do they know I already watched this whe it was first released

  • Subscribed :)

  • People don't want to hear the truth. They ignore the facts ⚰ and are proud to convince others to vaccinate💉 🆘️ Fear of God

  • Great video!! Just clarifying that almost no vaccine is really 100% effective against hospitalizations and death, there are always exceptions in the real world, specially with new variants emerging. Those 100% efficacy rates against death in the trials aren't statistically relevant because there weren't enough cases in te placebo group

  • I afraid of taking vaksina because of I have asthma can I take this vaksina or not ? you in my country whisdrawing from job i need work

  • Eu comparo!! Umas tem mais eficácia que as outras..

    • Você não assistiu ou não entendeu o vídeo então. Porque é impossível compará-las pois cada uma fez seus estudos em momentos diferentes da Pandemia locais diferentes e com variáveis diferentes.

  • Defending j&j

  • if you are in a rich country you have the previlage to choose, while other who are less fortunate will take what ever available vaccine.

    • we are desperate to get the vaccine while the richer once such as the US get to choose

  • If all the vaccines prevent hospitalisation and death, then surely the ones with the highest efficacy are the best since you're less likely to even get sick. The only issue is that the results aren't reliable due to the differences in the clinical trials, but theoretically, higher efficacy is better.

  • I don't belive in science, doctors...anymore. i don"t want that poison.

    • @Sapphir33 no way!

    • Why so? Vaccines are simply inserting the blueprints of the virus into your immune system. Teaching your body to prepare to fight covid if you encounter it. Meaning that this will make sure your body immunity is strengthen for the rest of your lives. This had been done over decades and you probably already got vaccinated when you were young from things like measle etc. Please vaccinate yourself and build an immunity for everyone.

  • You know even in 21st century theres still people outside the mental hospital free and refused to be vaccinated, more afraid than the cure...when they should fear the virus.

  • wanna bet? out of all moderna has the least side effects.

  • Thank you Detroit Mayor. because of you we got a clear explanation about vaccines

  • Superb video. Thank you.

  • Thank you for this video now I understand how these efficacy rates were derived. Just got my J and J shot few days ago. 🙂

  • Well, I'm not taking the Johnsen and Johnson vaccine

    • why not? did you even watch the video?

  • I’m so tired of people who didn’t even pass 10th grade biology airing their opinions on p complex immunology

  • Basically each vaccines have different effect on someone but will give the same end result.. Get your vaccine folks!

    • Have fun getting bels palsy

  • we seen the so called deadly virus..my whole family affected by covid,i was with them but no affected me and they all surpassed it so easy..so why to risk to get injected by a vaccine that is not fully licensed and while i was in the middle ,i didnt catcc it

  • actually they are still performing the "trials" ... let me take a look at your arm.

  • The lack of easily attainable information is what fuels the anti vaxxers

  • Just get it while it's free

  • It's all poison

    • then why tf do covid vaccines even existed?

  • The romantic night exceptionally pop because offer rahilly transport with a aloof permission. likeable, xenophobic otter

  • The best vaccine is the one you choose and feel safe to take. Choice is paramount, and ought be respected. Those over 60 are given no choice, told it's Astra zeneca or nothing even if they are prepared to pay for it themselves, thus left in danger of Covid infection and death.

  • You guys need to upload this in your different social media accounts so that we can spread awareness more, cause you guys explains the situation easily than the government does

  • Vox is really good at designing infographics that make complex topics more digestible. I appreciate all the effort!

  • Truth. I got the J&J a couple months ago and this week I've been getting sicker and sicker but it's not severe (yet and hopefully not at all). My whole work shift has the same symptoms. My County in my State has the highest delta spread right now. If I do have Covid, oh I'd hate to see how I'd be doing if I didn't have the shot.

  • That's it

  • Finally.. a better way to explain efficacy rate.

  • did they pay you to make this

  • basically effective rate lol

  • i hope there would be a vaccine for kids and youngsters thats as effective and as safe as the one's the mature ones gets...🙏🙏🙏🙏🙏

  • Lesson of the day: Everyone needs to learn immunology

    • this ain't even the basic immunology. face palm*

  • Meanwhile Canada is mixing vaccines 🥴 Lord help us smh 🤦‍♀️

    • @Jakob Hellyer Nice

    • I don’t know if it safe to mix vaccines. I was lucky and got 2 doses of Pfizer

  • Being an engineer in the medical field, I understand this. To summarize, the efficacy numbers can not be compared between the vaccines because they werent done during the same period of time with the same set of conditions. You're basically comparing apples to oranges. The numbers should not have been highlighted by these news agency at all.

  • I think that mayor should resign now hes incompetence thinking he is with reason to give the best of his people. Who knows what he will do to gain anything in his interest.

  • its funny how they are saying today that J&J should be removed.. seems like J&J may be the best vax.. lol.. as we know Israel has proven Pfizer is 64% at best..

  • this video proves nothing.. only 8 people got CV19 that where vaxed and 163 unvaxed. where these people required to go in stores daily and spend hours in these stores? most states where in lockdowns so they couldnt live life normal..!! this is a failed test, unless people are forced to be in public. getting a shot and sitting at home most of the time proves nothing..

  • so take whichever vaccine available and stop bothering government ! right? even though I cannot find any proper research and data on vaccine that is being offered by government? it might be different depending on where you live!

  • Where's the SINOVAC?

  • AstraZeneca is better for mutations. Just EU based complottism due no European vaccine. Bruxelles should say thanks to Johnson and Trump for the patience

  • Thank you but no, thank you. Shove those 'vaccines' up yours!

  • Its pure business...

  • Where is sinovac?? Hahahaha Im from the philippines and I don’t trust china, i wait longer for j&j to arrive in my hometown and I’m ready to vaccinated with j&j next week,, because only sinovac is available compare to j&j is limited stocks with appointments

  • A Covid vaccine is less effective than a Measles vaccine at doing its job properly the scientists cannot actually guarantee that it will sto you getting covid it's the only thing they have in their armoury

  • So if both the placebo and vaccine groups didn’t get COVID there would be 0% efficacy?

  • Video fails to mention that having any of the vaccines considerably lessens the immune system to look for and make it's own antibodies in future and relies on external help like a vaccine

    • That’s not how vaccines work but okay

    • That's what big pharma are relying on ,they need you addicted to it.$$$$

    • No that's not how it works, our immune system ALWAYS uses external "help" to train itself such as viruses. There's never been any internal "help" unless you count autoimmunity which is bad enough as it is..

  • 5:16 So the vaccine efficacy is broken down to % Death, % ICU, % Hospitalized, % No Infection. How is the other criteria calculated? When you look at the figures at 2:10 with placebo Vs infection, does % death % ICU and % hospitalized use figures from the 162 people tested or is it from out of the 8 people who got infected and later on developing worse conditions?

  • Yikes lol definitely not getting this