Need to know more about these children.
Age distribution? (mostly teens rather than small children?)
Are they “undocumented” and perhaps already very sick when brought across the border with no medications?
Are they in group-homes with crowding, poor sanitation & sub-standard care?
Are there other factors involved that leave them vulnerable? Cancer, immune-suppressed, diabetic, etc.?
It’s known but not widely reported that RSV is going around and that kids are susceptible to it.
I’d bet everything I own, it’s not COVID the kids have but that and it’s being misdiagnosed, deliberately likely as not, because these days, EVERYTHING has to be COVID.