I am going to say what no one else seems to be saying here. Best practices were NOT followed, at all. The youngsters, if I understand it correctly, went out into the world among other kids, and/or adults, to participate in three different sports activities. That doesn't sound cautious to me. Maybe I'm reading it wrong. If so, please correct me. It seems like there's no reason for surprise here. I wish them all the speediest and most thorough of recoveries, with no relapses or long-term effects!