I use to teach school also.
Every time I turn around I hear another parent having caught Covid after confirmation that their chidren have Covid.....not good...the same goes for families with every other health issue that can affect the lungs. I agree.....and sorry to say....they are " little disease factories" as
hbarbh said above. They don't understand the need for all the sanitary precautions one should take. Example: Washing your hands...and often.
Glad you have some answers to your question from "those in the know" and so helpful to us.
Barbara