Currently, hundreds of millions of people face the choice to 

(1) get vaccinated against Covid-19 (maybe choosing between different vaccines)


(2) do nothing

Given the fact that both the vaccines and contracting Covid-19 pose risks (in a sense that they may lead to significant reduction of quality of life), it is natural to approach the question whether to go with (1) or (2) from a decision-theoretic perspective. In other words, it is not obvious which of the two (or more) options listed above is the best option considering only self-interest. 

Take e.g. me, I expect to live for at least 50 more years (likely much longer). I am almost exclusively interested in irreversible long-term effects or death rates. It absolutely blows my mind that given the number of people in my situation, after a couple hours of research I have not found much information to support my decision. 

There is: 

  • some information regarding potential long-term effects of Covid-19 infection
  • Excellent data regarding my exposure and likelihood of Covid-19 infection
  • Excellent data on reversible short-term effects of vaccination (which are negligible) and short-term mortality

What is totally missing is: 

  • Predicted long-term effects of vaccination
  • A handy comparison of predicted long-term effects from vaccination and Covid-19 infection

I get that there is sparse data regarding the long-term effects of getting vaccinated. But certainly predictions can and therefore should be made. 

What I would have liked to find is a risk calculator that takes into account the most important variables and compares expected loss of quality of life from multiple scenarios. It would be fine if these could be heuristically expressed as e.g. odds of dying + odds*degree of permanent neural impediment due to the choice. 

Does someone have an idea what to do about this? Any information would be much appreciated and surely helpful for many.


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Besides the short term side effects we currently don't have "predicted long-term effects of vaccination". For practical concerns rounding that number down to zero is the best way to think about it given that COVID-19 comes with significant chance of long-term negative effects. 


This is my confident understanding as well. All who say 'long term effects' are purely basing this on the 'we don't know there aren't such effects' style of argument and nothing more, when there's every reason to believe that if there were such effects we would see signs of them by now and no plausible mechanism for long term effects. 

Whereas Covid-19 definitely does have substantial long term negative effects reasonably often for those who don't die - as OP notes, the estimates are loose, but Long Covid is definitely a thing. 

I would rate 'possibility of unknown long term side effects we have no reason to expect whatsoever' to be much less of a reason to not get vaccinated than 'you might feel bad for a day after getting it' even with a long term orientation. It's that small.  

It's also the nature of unknown unknowns that you can't include them in the kind of risk calculator that the OP asks for. 
Is only 1/3 of Long Covid sufferers actually having had covid definitely a thing, too? I think it is (or maybe antibody tests give many false positives?)

Thank you very much for your educated inputs. This definitely nudged me much closer to getting vaccinated. 



In order to weigh about the possibility of long term effects of the MRNA covax (Pfizer, Moderna), we need some plausible categories of mechanism; my understanding is that a known-harmful spike protein is produced in some quantity (surely dose dependent; why do they dose large people the same as small?) which may cause some clots or other harms acutely, but then days later spike levels are back to zero at which point there's nothing more to worry about except lingering cancer type damage that won't heal fully, and autoimmune (more likely in case of response to covid exposure than broadly own-tissue-attacking which we'd have seen already after 100m doses). I've heard no specific evidence that the spike insult or the MRNA mechanism would cause either but those are the categories of risk as I see it, FWIW.


If you aren't vaccinated you WILL be infected eventually.  

If case counts continue to decline, there will be a significant number of people who are never exposed.

I expect it to return as an endemic seasonal virus, especially in areas of low vaccination uptake, with continued antigenic drift allowing occasional mild infection of those with immune memory after enough time has passed.  It's the first infection of a naive set of lungs that matters though.
I'm thinking of the vaccines as a time machine. Imagine if you will that a time traveler could go back in 15 years and release the virus into the population, with no interventions or treatments. Lots more people would get sick and die, and we'd get enough herd immunity to turn it into a mild seasonal illness, mostly for children. The vaccines get us to that point without the use of a TARDIS.
FWIW I expect the equilibrium severity in the absence of continued immunization and presence of continued drift whenever it manages to slip through preexisting memory to be rather worse than the other human coronaviruses, at least for a while.  This bugger has a clutch of fancy accessory proteins that help hide from and screw up immune reactions, and for other reasons is very good at forming syncytia and infects such a wide range of cell types.  But NOTHING like what happens when people get it never having seen anything like it.  Think closer to flu on the cold and flu spectrum.  But we deal with that, and the antigenic drift after this explosive adaptation-to-humanity phase should be slower than we are dealing with now.  All the evolution we have seen lately is about becoming better able to infect human cells, with mild immune evasion from previous memory a side effect.  It is even possible that once the primary selective pressure is for immune evasion, the infectivity declines again due to the different set of trade-offs encountered - the best analysis I have seen of the D614G mutations that took over the world in the first half of 2020 suggests that it increased the avidity of the protein to human cells at the expense of making the S1 domain more open to neutralization and immune deactivation by immune memory, but this did not matter because all the infections were directed towards those with no memory. Decent possibility that over the coming decades the fancy accessory proteins (which are very necessary for infection in bats, less so for humans) start falling to bits due to Muller's Ratchet, as mutations that degrade them hitchhike along for the ride with spike and nucleocapsid mutations that actually allow infection of those with immune memory.  This already sort of happened once in the Alpha lineage, where accessory protein ORF8 that hides T-cell epitopes from the immune system broke but got dragged along for the ride linked with a spike that was better at at

How much lower is the chance of being 'infected eventually' if you keep current on your annual (or whatever it ends up at) corona vaccination booster?

I actually care a lot less about 'never getting it' now, since I will never have to deal with that first burn though me when I have never seen anything like it at all since I am vaccinated.  Any memory is good, even in the face of drift or waning. I couldn't tell you if there will be updated boosts over time.  If so, they'll certainly help...



Why do you think there is any risk of long-term loss of quality of life from the vaccine? There just isn't a reason to think there is a risk there. Your only finding one side because there is only one side.

Since I (or for that matter most people) do not understand the working mechanisms of the vaccines completely, I can not rule out the chance of significant long-term effects.

I'm no microbiologist either. I can't cite a paper to tell me there's no risk of heart disease from pumping my own gasoline. But I also don't have a model of the world that suggests any connection between pumping gasoline and heart disease, so I don't worry about it. Most things don't cause most other things. So just on priors, there's no reason to worry about this.



Any such evaluation should be accompanied by an evaluation of the risk(s) to others around you should you decide to not get vaccinated. You can do the relative weighing of the two risks yourself, but the weighing should be done.



There are no known long-term effects of vaccination, for any vaccine administered in history. Ever. That's why you should not be worried about that. 

Dr. Fauci's short answer here: , I am sure you can also find a long-form version or a relevant paper.

That seems a bit overconfident. Immunity is one supposed long-term effect. Death is another long-term effect though obviously infrequent in approved vaccines.

Apart from the things Jonathan mentions, the Pandemrix vaccine used for swine flu seems to have caused narcolepsy in rare cases.

Note that Fauci in that video is talking about delayed effects, not long-term effects.