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 🙂