Thoughts?
It seems this is an outbreak of EV-D68, one of many enteroviruses.
Some enteroviruses can cause serious disease, even death. Being enteroviruses, they are spread through feces. Little kids aren’t very good with hygiene, so these viruses spread fairly easily in children.
This particular enterovirus is not as serious as polio (also an enterovirus), and some other EVs have more fatality, but it seems to be pretty serious.
There is no vaccine and no cure for this virus. Basically, the kids have to receive supportive care until they can fight off the virus.