New York and New Jersey have announced their own mandatory quarantines, using their own (State) authority.
We can add Illinois to that last, too.
Here is a short firsthand account from one of the first people put under mandatory quarantine, a nurse returning to NJ from Sierra Leone.
By the way, this is the same unnamed person that Gov Christie had announced that returned from West Africa with a fever. The article explains how the infrared temperture "gun" can easily be fooled into displaying a higher temperature.