I just don't know what KSU could have done short of sealing all kids in a plastic bubble 24-7. One of my best friends, who is a young, divorced parent with a respiratory issue went on lockdown at home when this all started months ago. No one in or out of her home. She never left home (all but riding bike once in a while, and a few times curbside no contact pick up to go). All deliveries disinfected before being touched. The only contact with humans was he oldest son, who also locked down with her. She did this for over 3 months. Still got covid.
It is what it is. It is going to spread.