[arrrg]

This is all crystal clear by now. We know how Covid-19 spreads.

The height of infectiousness is just before or around the start of symptoms. You are infectious maybe a day or so before symptoms start. You aren’t infectious for that many days. This means pre-symptomatic spread is a major factor.

Truly asymptomatic cases also exist but they aren’t that common (and many of those, if examined very closely, turn out to be cases with symptoms, just extremely mild ones). So presymptomatic spread most certainly is a major factor. It’s how this virus can spread so effectively without non-medical interventions and vaccines (which, yeah, also reduce transmission).

That’s basic virus 101 and while we didn’t know a lot about this in mid 2020 we do know a lot about this know. This isn’t even speculative or on shaky ground, this is quite solid science.

It blows my mind that people do not know this.