Articles, Blog

5 common flu vaccine excuses | Infectious diseases | Health & Medicine | Khan Academy

November 20, 2019

Whenever I talk about
flu vaccine with people, I often hear the same
questions and comments coming up over and over again. And so I put a
short list together of really common
things that people say. And I wanted to discuss
them one by one. So let’s say this
person over here to the top left, this
person, she says to me, well, you know what? I don’t really see the
point of getting the vaccine because I never get sick. She says many
years have gone by, and her immune system has
just been really healthy, and she just never
seems to get sick. So she just doesn’t see the
point of getting the vaccine. And in response to this, what
I usually draw an analogy to is seat belts. And I’ll say, well,
many people have never been in a serious car accident,
but we know from research that seat belts are
a really good idea, and they keep you safe. And they reduce the risk of
getting a horrible injury. And so just as I would recommend
you wear the seat belt, or maybe you wear
a helmet if you’re doing something
dangerous, similarly, I would recommend the flu vaccine. And usually when I explain
it this way, people get it. And they say, oh, OK, well
even though I’ve never gotten in a major car accident,
I do wear my seat belt. So just like that, even
though I’ve never gotten sick, I’m going to go ahead
and get my flu vaccine. Now, on the bottom
left, this gentleman is saying a little
bit of the opposite. He says, well, you
know, I’ve gotten the flu vaccine, Dr. Desai. But I still got sick. I did it last year,
maybe the year before, and I still got sick afterwards. So what was the point? Why did I even do it? And so now I don’t
want to do it anymore. And I can understand his logic. That makes a degree of sense. And what I usually
tell folks that say this is– I explain the
idea of a copycat virus, that maybe when they got
sick with what they thought was the flu or the flu
virus, that maybe it was one of these other viruses. Remember there are viruses
such as RSV, or rhinovirus, that can sometimes make you
feel like you have the flu. So maybe he had one of
those viruses instead. Another explanation
could be maybe he got sick right after
he got the vaccine. And remember, the vaccine
needs a couple of weeks. There’s a two-week
delay or so before you get the full protection
from the vaccine. So maybe he was in that
two-week time span right after he got the vaccination,
and maybe he got sick then. And lastly, we have
to remember the flu vaccine has three strains in it. So maybe he had a
different strain. Maybe it was just one
or the other flu virus strains that was
out there that year. So who knows exactly
why he got sick that year that he
says he got sick. But that doesn’t change the fact
that the flu vaccine is still going to reduce his chances
of getting sick in the future. Now, one thing, I’m going
to stick with this gentleman here in the bottom left. He might say, well,
a different strain? What the heck? If that’s the case,
then what’s the point? I often hear that. He says, what’s the
point if you could have a flu illness
from some other strain? And when people
talk about this, I have to remind them
that it’s not perfect. So it’s not an exact science. And what you have to
remember is that it goes back to the seat belt issue. It does reduce your chances
of getting sick from the flu, but it’s not going to
reduce it down to zero. Nothing in life is going to
reduce your chances to zero, and there’s still a possibility
that you could get sick. And so our best
offer is that you can reduce the chance
of getting sick. Let’s move on to this
gentleman in the middle then. And so he says to me,
well, you know what? I think that the flu
vaccine made me sick. So this is a little different. He’s saying that the flu
vaccine itself made him sick. And this is something
a lot of people think. They think, well,
maybe I was fine, and maybe it was only after
getting the flu vaccine that I got sick. And this can be a very
frustrating thing to feel. I mean, that’s horrible
that you were feeling fine, and then a vaccine came along
and made you feel awful. But a couple of facts
have to come to mind. So one fact, for example,
is that we know that the flu vaccine cannot give you flu. So we know flu vaccine
does not cause flu. That’s a fact. And the reason I can
say that with certainty is that one of the two
vaccines is actually dead. Remember, there’s the TIV
and then there’s the LAIV. The TIV is a dead vaccine,
meaning the virus inside of it is dead. And the LAIV– that’s the other
option– this one is alive, but it’s very weak. And so usually with this one you
might get a runny nose at best. And so, if he says, I
think that I got sick from the flu
vaccine, I would say, well, I don’t think that’s
possible from this one, right? If you got the injected
version, then that’s not possible at all. And if you got the
live version, then you may have gotten some
symptoms, but we wouldn’t call that the flu. And I would also say that
if that weak vaccine made you sick, can you
only imagine how you would have felt if you had
the wild virus, the one that circulates and we’re
trying to protect you from? What’s much more likely
for this gentleman is that he probably got sick
from maybe this copycat virus, one of the other viruses that
are circulating, probably around the time that
he had the flu vaccine. So he mistakenly thought that
the vaccine made him sick when it was probably
just another virus. Or maybe he got sick
when he was still within two weeks of
getting the vaccine. Because, again, we said
before that it takes a couple weeks to really
get up and running. So in the top right, now we
have this guy and he says to me, well, you know what? I hate pain. And this is probably my excuse. This is the one I
used to use a lot. I hate pain. And I hate getting vaccines
because usually that means a lot of pain. So for folks like this, and
again, this was my own mindset, I say, OK, well, if pain is
what you’re trying to avoid, think about the fact that flu,
getting sick with the flu, is much, much worse
than getting a sore arm. And that’s the most common
side effect people talk about with that TIV vaccine,
the dead vaccine. And also, if you get the other
vaccine, the live vaccine, then I would say,
well, flu is still a lot worse than
getting a runny nose. And that’s the most
common side effect that people talk about
with the live vaccine. So when you think about
the common side effects, flu is much, much
worse than the side effects you get
with the vaccines. So we come down to this
lady in the bottom right. She says to me, well,
you know what, Dr. Desai? I think you’re a nice
person, but I really don’t trust vaccines. I don’t think that
they’re safe, and I don’t trust what’s
inside of them. I think that there is
something dangerous about them. And specifically, I don’t like,
she might even say, thimerosal. Thimerosal is something that
people talk a lot about. And it’s found inside of
some of the flu vaccines. And so that’s what
she’s referring to. So, in response, it’s tough. It’s tough to talk about
issues if you’re not trusted. And so the first and
easy thing to say is, well, if you really just
don’t trust thimerosal, some of the flu vaccines, the
single-dose kind of vials of flu vaccines, they
don’t even have thimerosal. So single-dose vials
don’t have thimerosal. So that’s kind of an
easy solution, right? If that’s her biggest
issue or concern, then you can just say,
well, fair enough. That’s an easy fix. And sometimes that works. Sometimes that’s good enough
and people say oh, OK, well, if they don’t have it,
then I’ll go ahead and get the single-dose flu vaccine. But for others that simply
just don’t trust vaccines in general, because they’ve
heard about thimerosal, or they’ve heard
about autism, things like that, there I think it’s
really helpful to just discuss where these things come from. Where did this whole idea
of thimerosal or autism– where was it born? And the truth is that there’s
a complicated history to that. And there’s a huge thimerosal
myth that has been born and people discuss
on the internet. And so I’ll talk about
thimerosal myth and the facts behind it because
that’s the only way to garner a little bit
of trust with folks, is to actually
discuss the facts. And actually separately
from this video, we have a thimerosal video that
you can watch and understand as well.


  • Reply Eli Hernandez January 19, 2013 at 6:34 am

    You should watch "In Lies We Trust" on youtube. Its over two hours and 30 min

  • Reply khanacademymedicine January 19, 2013 at 8:44 am

    That's true for most healthy young folks, but sometimes the flu can cause even the healthiest folks to land in the hospital. Why take that risk?

  • Reply Ethan Glover January 19, 2013 at 4:20 pm

    I don't get them because it's always the people who get vaccinated who get the flu. I used to get some sort of flu every year until I stopped getting them. I have got so much as a cold, or a sniffle for that matter since.

  • Reply Ethan Glover January 19, 2013 at 4:21 pm


  • Reply drakkan88 January 19, 2013 at 7:46 pm

    You guys should do a video about the shingles vaccine – I found out I needed it the hard way, the virus flared up in me about a week ago. Only 24 years old, always thought shingles was something older people got.

  • Reply Sid Dadlani January 19, 2013 at 11:16 pm

    Some people I have talked to have argued that getting the flu vaccine makes your immune system weaker. By that they mean that if one gets the vaccine, their immune system does not need to fight off this year's strain. Over time, their immune system does not work as well simply because it doesn't need to. Then, if a strain as deadly as the Spanish Flu comes along years later, their immune system will be too weak to fight it off. Does this argument hold any water?

  • Reply Tymon Johns January 20, 2013 at 3:29 am

    The flu virus mutates every year. By the time the vaccine is created, goes through testing, and is approved the flu has mutated enough that the vaccine has no effect. There's no reason to get the shot because it doesn't work.

  • Reply khanacademymedicine January 20, 2013 at 6:19 pm

    The flu vaccine challenges your immune system, and the only reason it works is because the immune system gets stronger. Over time, an immune system that has been challenged with vaccines every year is likely more prepared to handle a challenge like wild type virus like Spanish Flu, than an immune system that has been exposed to wild type virus some years and then had other years without any exposures at all (like taking some years off).

  • Reply Gila Atwood January 20, 2013 at 7:33 pm

    one of my kids was exposed to chicken pox when she was a baby and developed shingles when she was ten years old.

  • Reply Gila Atwood January 20, 2013 at 7:37 pm

    pretty much my attitude.. I'm at home all the time anyway and husband also works from home, we're both pretty strong and healthy and find the symptoms trivial when we ever get them, and when we do, we know how to take care of ourselves and avoid complications. Our doc (Canadian) doesn't push the vaccine at all. Perhaps in another ten to twenty years or so but not now. I'm 52, never had the shot.

  • Reply Gila Atwood January 20, 2013 at 7:37 pm

    excellent point.

  • Reply drakkan88 January 20, 2013 at 7:40 pm

    Yeah, I've been hearing more and more reports of younger individuals getting shingles as of late, likely because I'm just now looking for them. Don't know what the dynamics are with regard to your Immune System & supression of Herpes Zoster – Doctor reckons it's due to stress level that weakened my immune system (prior to this I haven't been sick for over 4 years). Ugh. Biology stumps me.

  • Reply James Daher January 21, 2013 at 12:27 am

    Why do some people not trust doctors?

  • Reply Zinaida Bolboceanu January 21, 2013 at 5:40 pm

    hello, khan academy needs a video about the lymphatic system 😉 , please make one, it would be great

  • Reply akshay kamath May 9, 2013 at 7:10 pm

    especially in india people don't trust doctors cos all are fake ,they bribe the authorities and get their degree and without knowing anything about medicine they practice them killing a lot of people!

  • Reply RobertAculaMD May 13, 2013 at 5:58 am

    This is what I don't understand about the flu vaccine- if the flu vaccine is formulated to protect the population from the current prevalent strain of the flu virus, how would the pharmaceutical companies know which strain poses the greatest threat and design/release the vaccine in time and have it tested for safety and efficacy, which generally go through several phases and several control/experimental groups- a process that can last several years?

  • Reply Jennifer Hawkins July 10, 2013 at 11:05 pm

    Flu vaccines have already been debunked by the Cochrane Collaboration, they don't work, fake studies were used to justify them

  • Reply 03251981aj July 16, 2013 at 8:39 pm

    You left out the KEY which is their are literally thousands of strains of the FLU and the so called FLU shot only protects against a few of them. Most of the time by the time the new FLU batches hit the market it has already MUTATED.
    In other words at best it's a shot in the dark, while if you take a FLU shot you will without a doubt get the FLU in the first place, at least all the symptoms you hoped to avoid with the shot.
    So then what are the benefits of a FLU SHOT???

  • Reply Max July 28, 2013 at 2:03 am

    jesus christ!!! where did you learn to draw so well???

  • Reply KJ V September 27, 2013 at 1:57 am

    Mayo Clinic says in rare cases the flu vaccine can cause Guillain Barre, so why risk that? I'm still not convinced.

  • Reply amfcrew November 27, 2013 at 11:07 pm

    This is some bullshit. The only people I know that get the flu each year is the people who get scared by their doctor into getting the shot. Stick to math.

  • Reply EdR77203 December 20, 2013 at 6:02 am

    There are adjuvents in all vaccines.  These kick the immune system into reacting to the antigens.  What stops the adjuvents there?  Can the vaccine adjuvents explain the epidemic of immune related issues?  The medical community is mute on this issue.  They have no evidence one way or the other.  The only way to collect such evidence is to compare unvaccinated to vaccinated.  That is something that the medical community steadfastly refuses to do.  I will not get the flu vaccine.

  • Reply Eric Palmer December 22, 2013 at 9:34 pm

    Just buy the vaccine guys.

  • Reply Eric Palmer December 22, 2013 at 9:42 pm

    I'm not an alarmist, or against vaccines, but this one is definitely not proven to be worth the effort. I also don't think anyone is obligated to be part of a herd.

  • Reply Rockwater Renee November 25, 2014 at 1:59 am

    buncha bull shit!

  • Reply Chris Porro July 21, 2015 at 8:56 pm

    i believe people should have a right to choose. they should also have informed consent. the more people i talk to the more i realize how little the general population knows about vaccines. they don't know about the vaccine courts. they don't know what thimerosal is. they don't know the long toxic history of mercury. they don't know many of the things that parents of autistic kids know. they don't know about the adverse reactions database. they don't know the way vaccines are handled outside the US. they don't know how the vaccine schedule has change in the last 20 years. they don't know about the 100% vaccinated populations that got measles.

    in short, they are pretty ignorant. and so was i until i had a child and started looking into it. there is a whole other story, with real doctors, real researches, and it's not being told. many of these issues are never discussed in the big media.

    after the public understands both side then they should make the decision. what they are doing now is ignorant compliance.

    i also think it's American, unconstitutional, and a real bad idea to mandate vaccines that come from a for profit pharma industry. no wonder the vaccines schedule is about 3 times the size it was when i was a kid.

    let parents choose the medical procedures their kid gets. have some faith that parents are the number one advocate for their child's health not the CDC, not the FDA, not pharma. we aren't stupid. we aren't malevolent. i believe the thousands of parents with injured kids not the vaccine manufactures. 

    i could tackle the myth of "heard immunity" but instead let me link to an outbreak of 100% vaccinated kids published in the new England journal of medicine. it's not the only outbreak to contain high numbers of "vaccinated". ask yourself how this works with herd immunity.

    vaccine are like religion and politics. people know little about them but have very strong opinions.

  • Reply John Williams December 2, 2015 at 10:36 pm

    So what about the court cases in Italy that proved some vaccines caused autism?

  • Reply Ching Lam Yung November 19, 2017 at 8:01 pm

    Comments are cancerous. Don't read them.

  • Reply douglas kuchenbecker October 26, 2018 at 6:18 am

    flu shots are as little as 3percent effective

  • Reply newmedstudent November 30, 2018 at 3:55 pm

    Time to unsubscribe..

  • Reply tecnolover2642 April 27, 2019 at 11:44 pm

    Stick to math bud.

  • Leave a Reply