[stupac2]

If only one kid in that classroom gets C-19, at least 50% will have it within days. In viral load studies on children in elementary schools in the USA, there was about a 99% chance of at least one kid with a viral infection in the classroom every day of the school year if there were 25 pupils . Taiwan isn't achieving anything at the elementary school level. All of the prevention is happening elsewhere.

What is that number based on? If each pupil has a 1% chance to be infected at any given time (which is likely high since we're looking at 1% total incidence over the last few months) the odds of a classroom having one infection are like 23%. That's of course assuming an independent variable which isn't true (since a kid is probably most likely to get it from another kid), but if anything that makes the percentage lower because of clustering (assuming you follow guidelines like CA's current ones, with no classroom mixing and dedicated teachers).

I fully believe that my simple math could be missing something of immense proportions, but to get to 99% you'd need something like 15% incidence, just something wildly unlikely.

I can't speak for Akiddoc, but that study of the Korean call center is probably informative here . Dozens of people got the virus in a shared office, and iirc bathrooms were hypothesized to be involved in the spread.  Classrooms are way smaller, and kids are bad at hygiene.  The 6' spacing thing may protect you when passing someone on the street, but being 6' apart is probably meaningless when you are talking about 30+ hours a week of it.

I think it's essentially impossible to keep the virus from spreading in a classroom.

Actually, I see now that I misread, the study wasn't covid-specific, it was just that virtually every classroom in America has a kid sick with something at any given time. Now that's a finding I believe. Although I'm not sure how informative it is for our current situation, where the incidence of covid is a lot smaller than "all the other viruses".

[stupac2]

If only one kid in that classroom gets C-19, at least 50% will have it within days. In viral load studies on children in elementary schools in the USA, there was about a 99% chance of at least one kid with a viral infection in the classroom every day of the school year if there were 25 pupils . Taiwan isn't achieving anything at the elementary school level. All of the prevention is happening elsewhere.

What is that number based on? If each pupil has a 1% chance to be infected at any given time (which is likely high since we're looking at 1% total incidence over the last few months) the odds of a classroom having one infection are like 23%. That's of course assuming an independent variable which isn't true (since a kid is probably most likely to get it from another kid), but if anything that makes the percentage lower because of clustering (assuming you follow guidelines like CA's current ones, with no classroom mixing and dedicated teachers).

I fully believe that my simple math could be missing something of immense proportions, but to get to 99% you'd need something like 15% incidence, just something wildly unlikely.

I can't speak for Akiddoc, but that study of the Korean call center is probably informative here . Dozens of people got the virus in a shared office, and iirc bathrooms were hypothesized to be involved in the spread.  Classrooms are way smaller, and kids are bad at hygiene.  The 6' spacing thing may protect you when passing someone on the street, but being 6' apart is probably meaningless when you are talking about 30+ hours a week of it.

I think it's essentially impossible to keep the virus from spreading in a classroom.

Actually, I see now that I misread, the study wasn't covid-specific, it was just that virtually every classroom in America has a kid sick with something at any given time. Now that's a finding I believe. Although I'm not sure how informative it is for our current situation, where the incidence of covid is a lot smaller than "all the other viruses".