Can't be emphasized enough. Even if simplified down to three groups:

1) immunologically naive (never been exposed to SARS-CoV-2)

2) vaccinated

3) recovered from previous infection

Most discussions on HN completely miss the distinction between these groups. The truth is, so far scientific consensus indicates that groups 2 & 3 are at least equally well protected and pose equivalent risk to others.

Much of the bickering here conflates groups 1 & 3 - it's such a common mistake I've grown tired of trying to discuss it.

> The truth is, so far scientific consensus indicates that groups 2 & 3 are at least equally well protected and pose equivalent risk to others.

Which reduces the set to two: immunologically naïve, and primed for an immune response.

Or as we like to call it, unvaccinated and vaccinated.

Edit: vaccination via live virus is absurdly foolish.

Aside from yourself, who is this "we" who likes to mislead in this way?

It’s me and my worms, buddy. Royal worms.

Live virus vaccination is (was) a thing. There is nothing unscientific about stating that there are only two classes of people: vaccinated against sars-cov-2 spike protein, and not vaccinated against the same.

> The truth is, so far scientific consensus indicates that groups 2 & 3 are at least equally well protected and pose equivalent risk to others.

If they are, then the immunologically naive are even worse off than vaccinated/unvaccinated data suggests, making vaccination even more critical for anyone without a certainly-known prior infection.

> Why is everything so black and white in studies

Because getting to black and white and cutting through fuzziness is the whole point of expending resources on a study.

> Does anyone care about nuance anymore? Just saying vaccinated and unvaccinated is a disservice to the population

Not if your goal is to isolate the effect of vaccine rather than to do some kind of fuzzy emotional handholding to people's instinctive, non-fact-driven subjective feelings about what groupings are important.

Moreover, because potentially the vast majority (estimates vary widely) of prior infections will have been undetected, outside of some very special study designs which would necessarily be much smaller and less population-representative [0], throwing in prior infection as an independent variable is going to be garbage data (and, even if it wasn't, any information from it would generally be nonactionable for the same reason.)

[0] e.g., using a subpopulation that is carefully monitored for infection, like healthcare workers.

> Not if your goal is to isolate the effect of vaccine rather than to do some kind of fuzzy emotional handholding to people's instinctive, non-fact-driven subjective feelings about what groupings are important.

I mean all the groups I presented have some sort of merit to them based off research (delayed 2nd shot), at least observational studies (previous infection then vaccine) or guidelines from CDC on other viruses (previous infection). Doesn't seem emotional.

Because it’s no longer about the vaccine.