Transmission of the corona virus in schools

keeps coming up. 
A certain professor who seems to spend a lot of time on social media and in the press keeps posting news of outbreaks saying , "Schools are safe. I can't be any clearer than that."  The irony is probably lost on many people. 
I know too many people who believe that (1) children cannot catch Covid19 and (2) if they do then they only get a few mild symptoms and (3) that any child who does had to be sick before that.
I am not sure where all that "information" came from - probably from a source similar to the one that stated getting your childhood vaccinations  causes autism.
When I was teaching there was a folk-theory floating around that teachers developed a sort of "natural immunity" in relation to the worse of the colds, coughs and 'flu like illnesses. We taught children didn't we? The little darlings didn't cover their faces when they sneezed, blow their noses in a hygienic manner, came to school when they were not feeling well and much more.
Of course teachers, like everyone else, had days off because they were sick. They didn't want to infect everyone else. 
I actually left the teaching service with all but one of my "sick" days still intact.  It wasn't because I was a particularly healthy sort of person. I was simply fortunate. 
In one school I taught at we had a teacher who was, quite literally, dying. She had cancer. She came to school right up until the end of one term. A week into the school holidays she died. How she managed those last few weeks of school I will never know. I don't think the other staff had any idea how ill she was. It was purely by accident I found out. I needed a child's walker from her classroom and she was in there alone.  The pain and exhaustion was obvious although you would not have thought she was so ill when she arrived that morning.
    "Don't say anything please Cat. If I can see it out to the end of term that will make it so much easier for everyone, especially the children."
I said nothing. I don't know whether it was the right thing to do or not. The other staff were shocked by her death. Some of them had actually believed she was recovering. Others had no idea she was as ill as that.
Her group of physically disabled and intellectually retarded children would only have been, at best, vaguely aware of her not being there the following term. It was a kindness to them that I won't forget. 
I often wonder though what would have happened if she had, perhaps a few weeks before, caught some virus or other. Would she have continued to try and come to school or would the excuse that "Mrs L... is sick" have been enough?  Quite possibly it would have been.  
Now she would have been considered to be "highly vulnerable" and nobody would have expected her to be at work.  We might have been better informed about her cancer too. 
School was not a "safe" environment for her to be in. She was not going to make others ill but they might well have made her even sicker than she already was. 
Possibly it is that way for many other people too right now. We just don't know. Do we put life on hold because of the corona virus? Or do we take measures to minimise, as far as possible, the potential harm?  Do we simply make schools as safe as possible?