@SockYarn
Teachers are exposed to all sorts of bugs all the time - norovirus, flu, general coughs and colds, slapped cheek, scarlet fever, nits, threadworms - all the stuff that is going around all the time.
When there's a huge winter vomiting bug outbreak you don't see the teachers demanding PPE and social distancing in case a child doesn't wash their hands and passes it on. And that's a much stronger possibility.
We get teachers are reluctant to return but tehy are in the fortunate position of not facing their positions becoming redundant. State schools will not close. Teachers will not lose their jobs. Parents who can't return to work because schools aren't open will. In huge numbers.
You said it yourself, that stuff is going round all the time. Any teacher who has worked a few years has built up resistance to a lot of the normal bugs. This is brand new, noone has any resistance. The possibility of catching it WAS higher...fortunately the R rate dropping has dealt with that. But the possible outcome is more than a course of tablets or a couple of days throwing up.
Nor does the entire country lockdown for weeks for those things. Nor does the country suddenly have 40000 deaths (and that's just the official number) due to those things. Nor do workplaces have to install screens / one way systems/ limit people in and out. Nor do people have to be furloughed or told to work from home.
As we have heard and nauseam, this is "unprecedented" at least in our lifetime. You can't compare it to the usual bugs we face every year. I say it again, 40000 deaths. And yes, most are elderly...but we have all heard of fit and healthy younger people hit hard or killed by it, maybe due to underlying health conditions such as asthma, maybe just unfortunate. Any assessment of risk should weigh up the seriousness of potential outcomes alongside the likelihood, and put in place measures to mitigate those risks.
Btw, I see now face masks are mandatory for public transport. People on a bus/train carriage are not generally cooped up together for 6.5 hours. They are less at risk than a teacher in a small classroom with 30 little people who don't all think/care/know about covering mouths when coughing or sneezing.
If the general public are being told to socially distance, reduce contacts and gradually encouraged to wear masks, how is it ok to say "but not if you work in school?" Try transferring that to any other group of people and there would quite rightly be outrage.
I guess we should be flattered that so many people see school workers as superheroes, invincible, indestructible. (Better hope our families all are too.)