These are reasonable theories as well. Though the second one would really have to be "SARS-CoV2 has more fomite spread than flu" to explain the observations.
In general though, any sort of explanation that focuses on differences in transmission is more plausible than hand-wavy theories involving R0 and masks. People just desperately want to find evidence that the stuff we did this year made a huge difference.
> People just desperately want to find evidence that the stuff we did this year made a huge difference.
I don't think that's true at all. People have been receptive to the increased evidence that transmission on surfaces is pretty unlikely, for example, despite all the efforts we've put into sanitizing surfaces.
I think most people can appreciate that all the shit we threw at the wall throughout the pandemic eventually comes down to how much effort it is vs how much benefit we get from it. And our understanding of each measure has changed over time. We now know, generally:
Masks indoors are low-effort, medium reward. Masks outdoors are low-effort, low reward.
Cleaning surfaces is medium-effort, low reward.
Staying home is (economically, societally) high-effort, high reward.
To be clear: I'm not making a specific argument about masks vs. sanitizing vs. whatever here.
I'm just saying: responses like the OP immediately leap to the conclusion that influenza went away because of all the stuff we did. It's an error in logic, driven by the emotional desire to believe that the stuff we did must have had a serious impact, and that anything else is not worth serious discussion.
> I'm just saying: responses like the OP immediately leap to the conclusion that influenza went away because of all the stuff we did. It's an error in logic, driven by the emotional desire to believe that the stuff we did must have had a serious impact, and that anything else is not worth serious discussion.
I feel like you're coming down too hard on OP. He makes a valid argument.
> immediately leap to the conclusion that influenza went away because of all the stuff we did
It's not an error in logic. It's a reasonable conclusion to draw based on what we've seen and the links he provided. Whether it's true or not, that's debatable and probably nobody here on HN is going to figure that out definitively.
I'm really not sure why you're so argumentative without actually providing any substantial arguments against OP. It feels more like you're the one arguing from an ideological basis.
> That said, if the massive reduction in flu cases isn't a result of some or all of our Covid efforts, it'd be a hell of a coincidence.
Mmmm...I wouldn't go that far. Like I said, my current preferred theory involves schools, but other plausible theories involve things like mutual inhibition: infection with one virus somehow interferes with infection by the other.
We have some evidence of this happening in the past. Strains of influenza have abruptly vanished due to this phenomena.
Certainly, I'd agree that this is interesting (which is pretty much where I end up on this, vs. the OP, who thinks the matter is settled.)
more generally, it's likely due to greater (indoor) distancing, of which school closures is a subset. the slight differences in transmission characteristics between flu and covid (also represented as differential r0) likely makes flu relatively more susceptible to reduction by distancing.
and distancing is a first-order mitigation that overwhelms the effects of inferior/ineffective mitigations like cleaning, sanitizing, mask-wearing, extra ventilation, etc. those secondary mitigations can make more of a difference when we want to pack it in, like at a movie theater, but otherwise they don't do much because those circumstances are relatively rare.
folks just don't want to accept such a simple answer because it means there's not much to hang their anxiety on, and that cognitive dissonance is unacceptable, as it always is.
In general though, any sort of explanation that focuses on differences in transmission is more plausible than hand-wavy theories involving R0 and masks. People just desperately want to find evidence that the stuff we did this year made a huge difference.