The use of physical restrictions on travel was designed for (and would be appropriate for) smallpox.
It's not appropriate for sniffles.
The call I mentioned above is actually by FEMA legal councel. They are going through a powerpoint deck. Slide 53 is titled “Quarantine and Isolation Law: The Basics”. Again, anyone can call and listen in.
Federal Powers: Quarantine and Isolation
The Secretary of HHS (through CDC) can: detain, medically examine, or conditionally release persons suspected of carrying certain communicable diseases
Authority applies only if communicable disease has been designated in a Presidential Executive Order SARS added 2003 Avian influenza added 2005
State and Local Jurisdictional Issues Regarding Protection of People
Remember: Police powers, including public health authority, are reserved to states under the U.S. Constitutions 10th Amendment
But: federal and international jurisdictional issues may arise in a given case