Entry into the country is a federal concern and the CDC can guide and advise the states. I hope that at least the medical community learned from the Spanish Flu.
That doesn't sound like border control (Ha!) to me.
Feds try exercising police powers like that in the States, there may well be pushback.
Recent events have shown that people won't put up with it.
The Feds did squat all during the Spanish flu epidemic, including at the WWI camps. Thousands died.
Waiting on government to do something right is a long wait where a train don't come.
/johnny