What a scientist means when they say “Person 1 didnt respond well to Vaccine A”:

Person 1 was given a vaccine. They did not generate a protective adaptive immune response from that vaccine (either B- or T-cell, whichever was supposed to occur). OR Person 1 did show an adaptive response initially, but there was no memory/short memory.

What a normal person means when they say “Person 1 didnt respond well to Vaccine A”:

Person 1 was given a vaccine. They got a fever/headache/passed out/etc.

As cold as this sounds, scientists dont exactly care about your fever and headache. Technically, those kinds of side-effects are a ‘good thing’– a sign your immune system ‘sees’ the dummy viruses/proteins/etc in the vaccine and is ‘learning’ how to combat the pathogen. The whole point of a vaccine is to generate that kind of response so you dont get the actual illness, which is a heckovalot worse than a fever for a day. Suck it up.

We are more worried about the individuals who get the vaccine… and nothing happens. Lots of vaccines are dead pathogens, or just chunks of pathogens. You can not make any kind of immune response to them, and they will degrade on their own. For example, one of my colleagues studies lupus patients responses to the influenza vaccine. Some respond well (make anti-influenza antibodies) some do not (get the vaccine, but make no anti-influenza antibodies) and a responder one year might be a non-responder the next, and vice-versa. When you are injecting people with dead chunks of influenza, they dont *have* to make an immune response to the dead chunks to get rid of them, so sometimes, they dont. The deadness of these vaccines makes them safe, but this is one of their drawbacks (vs the live attenuated influenza vaccine– you *will* make an antibody response, but you cant give the vaccine to someone with lupus. ‘attenuated’ influenza in a healthy person doesnt mean attenuated in someone with an immune disorder).

Another example, if a physician holds off giving vaccinations to a premature baby because they are concerned babby wont ‘respond well’, they arent concerned the babby will DIE from the vaccine. They are concerned the babbys immune system isnt mature enough yet to respond to the vaccine, thus you are giving babby a shot for no apparent reason. You are wasting your time because ‘babby wont respond well to the vaccine’. The components of the vaccine will degrade and babby wont be protected.

But its not just words that are confusing. Side-effects that appear ‘serious’ to normal people arent that big of a deal to scientists either. A really funny example came from an MSN article on a review of >1000 publications on vaccines (SPOILER: no major side-effects from vaccines):

Among the side effects vaccines can cause, Clayton said most are short-lived. The panel found that the MMR vaccine can cause seizures in people who develop high fevers after getting the vaccine, but these pass quickly.

“They are scary to be sure, but they do not cause any long-term harm and they are not a sign the child will get epilepsy,” Clayton said.

Sometimes people will get a fever so high from a vaccine they actually have a seizure. And a scientist is like “*shrug* No long term damage. Youll be fine.” While a normal person is like “OMFG MY KID JUST HAD A SEIZURE!!!!”

As long as the child made an adaptive immune response to the components of the vaccine, a scientist will say they ‘responded well’, while the parents will no doubt say the child ‘did not respond well’.

This is something that physicians could be explaining better, because its such an obvious point of confusion, but this is one time I cant look down my nose at them– I caught myself not explaining ‘not responding well’ properly when I watched my talk at FreeOK, so I am fixing it now 🙂


  1. #1 Reed A. Cartwright
    August 25, 2011

    We were listening to the radio in the car one day and they were talking to a pediatrician about diarrhea (cha, cha, cha). And he said that he often gets calls from parents with sick kids, who are freaking out over a fever. The parents are so obsessed with the fever that they don’t even notice that the kids are getting dehydrated. And when he tries to get the parents to do something about the dehydration, they refuse because the fever is not down yet.

  2. #2 Rayshul
    August 25, 2011

    I have learned something today, thank you!

  3. #3 Ed
    August 25, 2011

    Hm, the thing is people tend to be very bad about treating brain related or otherwise not obvious harm with an appropriate level of seriousness. That makes it all the more serious and important to avoid for people because others won’t understand/you can’t get any help or cure. Ironically most people seem to sort of get this when it applies to themselves at least when they first start thinking about it, but not to other people.

    Now I’m not saying it applies in this particular case, but when you look at examples of the attitude towards brain injury or other non visible injury in general (example: iraq war vets) people just sort of figure well, heh there are lots of stupid/ugly/unhealthy/disadvantaged people and no skin off my teeth if you join them. One more grunt/helpless person to serve me fries/clean up after me/crap on for some shits and giggles. Ka-ching! Like money in the bank.

    So when they say “not significant” they might mean not to *me*. As in well, yeah might ruin their live or someshit, but they can’t prove it easily, ‘specially not in court cuz cripples never have any money, so can’t sue us or at least win so no biggie.

    I think this sort of exaggerated(?) terror of fevers/seizures etc. will continue until people start to respect the less straightforward or obvious but still serious forms of harms you can suffer, and it’s not entirely without some foundation. Sure you can argue that the attitude is not commensurate with the problem according to the evidence, but the thing is that if people can’t trust the authority figures/scientists/government to do a fair accounting of the harm and have their best interests at heart, instead they seem to be glossing over the less obvious stuff, well….

  4. #4 JustaTech
    August 26, 2011

    My mom never responded to her many smallpox vaccinations (she had a lot of them because she never formed a scar). When I was getting my vaccinia vaccination I mentioned this to the scientist who was leading the study I was in, and he was so excited. “Oh! can we get your mom in for a blood draw? Would she concent to another vaccination?” He was terribly disappointed when I told him that my mom lives on the other coast and he couldn’t have her.

    But I’ve always wondered; did she not respond to the vaccine because she’s natually immune to the vaccine, and if so, would that have protected her against smallpox?

    (My vaccination was normal, if disgusting and uncomfortable.)

  5. #5 Prometheus
    August 26, 2011

    This is similar to forensic engineering in products liability.

    The engineers and techs high five the poor bastard in the flame suit and the lawyers get excited because the engineers are talking about how the test was successful and reproducible.

    Then somebody (me) has to explain to the suits that “successful” means that their product kills people in perfect accordance with the “first test scenario” to wit: the first event in which the product killed people.

    *sad trombone*

    I had one engineer grinning, giggling and waving at a lawyer who had just realized he had to advise a multi-million dollar recall,

    Engineer: …they just go whoosh and there is this huge gout of flame…..

    Me: Harold can I see you over here.

    Engineer: In a minute. They are like little rockets when you heat them up…..

    Me: Harold!

    Engineer: Okay. Okay. But they fry the skin right off the hands…

    Lawyer: *barfs*

  6. #6 Mary
    August 28, 2011

    I’m a non responder, but it’s because of the high steroid doses I take..or so I’ve been told…if I didn’t take steroids, I’d be fine..

    and because I’m immunosupressed I’m always debating on if I want to be vaccinated..

  7. #7 Bob Powers
    August 28, 2011

    Once again Abby writes something on an issue I had not given much thought to previously, explains it in a way that I easily grasp, and puts it in such a way I want to read the whole article.

    Kudos, for bringing a fascinating aspect of science to a layman once more.

  8. #8 W. Kevin Vicklund
    August 28, 2011

    Mary, if you’re on immunosuppressants, it is likely that you should not get vaccinations. However, this is a topic you need to discuss with your doctor, not trust to some random schlub on the internet.

  9. #9 Charl
    August 30, 2011

    I got the HV vaccine so I could play with human whole blood in the lab (yayyyyy!… shame there’s no HIV vaccine, occupational health *sarcastic face*) and each jab in the course was worse than the last – by the third I thought she’d injected lead into my bicep. But when I got my antibody titres back, I’d mounted a really good response to the vaccine. I could wish for a slightly less vigilant immune system, but if I ever meet HBV, I’ll be glad of the discomfort I felt from the jabs.

  10. #10 Epinephrine
    August 31, 2011

    W. Kevin Vicklund@#8, re: Mary@#6

    Definitely agree with the “see your doctor” part, but not about the “probably shouldn’t” part. Again, just another schlub, but any vaccines using killed viruses/polysaccharides/conjugated polysaccharides/subunit/toxoids are probably all perfectly fine.

    You may not develop immunity, but it’s unlikely that any vaccine without a live component would be harmful.

  11. #11 Slugsie
    September 6, 2011

    Maybe scientists should start using “Responded as expected/not expected” instead. That’s much clearer to us laymen.

  12. #12 Personal Perspective
    September 7, 2011


    Do you believe that this simplistic model of vaccine and patient interaction will stand the test of time and scrutiny as we all become more and more aware of the research that indicates far more complexity.

  13. #13 Personal Perspective
    September 7, 2011


    Are you also aware that when you say something like ….

    “And a scientist is like “*shrug* No long term damage. Youll be fine.” While a normal person is like “OMFG MY KID JUST HAD A SEIZURE!!!!” ”

    The OMFG may be the correct response for those infants and children with SCN1A mutation that is vaccine triggered. (Dravet Syndrome)

    For further reading I suggest The Lancet letter here –


    and the accompanying references.

  14. #14 Samantha Vimes
    September 7, 2011

    Do some people get massively delayed reactions? I had a chicken pox shot earlier this year, because I want to go into teaching and didn’t have immunity. But there was no reaction and I was nervous about whether it “took”. But a week later, the site swelled a little, itched, bled a tiny bit, (I think I also had a mild under the weather feeling) and I’ve been hoping that it just took a few days before my body noticed there was something there and took it seriously.

  15. #15 Jane
    December 12, 2011

    If you have a sore arm for a few days after a flu shot, is that a good sign?

  16. #16 Justin L
    February 16, 2012

    This was a very interesting article ERV, and I like how you “decoded doctor language” into common everyday talk. It seems from your discussion about influenza vaccines that it is more effective to get live versions of the virus because this is sure to provoke an immune response, but slightly more dangerous since you might actually get sick from this weak, yet still alive form of the virus if your immune system is week. One thing that I think is interesting is the current debate over the effects of giving children vaccine. In your article you discussed that it appears that the only side effects are short term ones such as headache, fever, nausea, with the most drastic being a seizure. However, there are currently many people who believe that vaccines may potentially have even more severe side effects, such as producing diseases such as Autism. Some research in this field can be found here: http://www.webmd.com/brain/autism/searching-for-answers/vaccines-autism. I wonder what you guys think, is there a link between vaccines and developing diseases such as autism?

  17. #17 NJ
    February 16, 2012

    Justin L @ 16:

    I wonder what you guys think, is there a link between vaccines and developing diseases such as autism?

    Go over to the Respectful Insolence blog on this site. Once there, search on “vaccines autism”. Read the numerous posts there with multiple links to the primary literature on the topic.

    Alternatively, take my word for it: No.

  18. #18 Nicholas Jerome
    February 16, 2012

    @ Justin L

    Don’t listen to NJ. I know him personally. He is a stupid canadian flouride pusher.

    NJ is easily recognizable. All ya gotta do is recognize his style, out him and prod him a little bit. And out comes a torrent of looney. The truly funny thing is that he doesn’t realize that he’s making a permanent record of his being unhinged.

    Viewed objectively, it’s a sad testament to the failure of his mother and father to teach him wrong from right.


  19. #19 JGC
    February 24, 2012

    Justin L @16

    There’s no evidence (certainly nothing beyond anecdote) to suggest a causal link between immunization and the development of autism. For that matter, contrary to anti-vaxer’s claims there’s no autism epidemic occurring: the increase in autism diagnoses is a consequence of diagnostic substitution and improved surveillance (it’s not that more people are developing autism than previously, but that disorders which were previously diagnosed as other than autism or that were overlooked by clinicians are now being recognized and idnetified as autism spectrum disorders).

  20. #20 Autismum
    February 29, 2012

    100% of people SCN1A mutation go on to have seizures. Indeed, the paper to which this letter is a response concludes “vaccination should not be withheld from children with SCN1A mutations because we found no evidence that vaccinations before or after disease onset affect outcome.”
    It must be noted that the letter was written by a person “testifying as a paid expert witness in the US Court of Federal Claims on behalf of a child with Dravet syndrome who had his first seizure after a DTP vaccine…”
    @justin L
    The proposed links between autism and vaccines has been found to be a temporal association. though it transpired that work by Wakefield in the late 1990s was fraudulent and the toxin theory was based on very tenuous observations and associations they were interesting theories and have be thoroughly investigated and each found to hold no water. As you may guess from my ‘nym I have an autistic child and would not and did refuse vaccination.

  21. #21 Personal Perspective
    April 21, 2012


    “100% of people SCN1A mutation go on to have seizures.”

    So you are agreeing that vaccines trigger epilepsy in genetically susceptible children. That’s the point of my comment … the two converge otherwise there would be no discrimination.

    “Indeed, the paper to which this letter is a response concludes “vaccination should not be withheld from children with SCN1A mutations because we found no evidence that vaccinations before or after disease onset affect outcome.”

    Except it triggered the epilepsy. Bit late to withhold vaccination after the fact.

    What it does suggest to the more complex thinker is that vaccines need to be carefully researched in some specific paediatric populations. For instance those with an immune system dysfunction / autoimmune or autoinflammatory disease.

    Or those populations that have ‘aberrations’ in gene expression surrounding genes or signalling hubs that drive responses to say infection.

  22. #22 Pushtrak
    April 27, 2012

    There is going to be a 36 hour charity event to raise money for HIV research. http://www.youtube.com/watch?v=IcYYoziGnq4

  23. #23 Air Jordan 7/16 Countdown Package
    July 4, 2012

    Nice post, just found your blog on my travels around the Internet. Definitely will come back.

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