Seattle area schools just shut down, and earlier today the governor put restrictions on gatherings of more than 250 people. Seems like it’s moving pretty fast.
it won't be mandated by the federal government nation wide but you'll see it (and it's already started in some places) at the county level and maybe state level.
Fulton County, Georgia (Atlanta) shut down all schools after a teacher was diagnosed.
San Francisco is banning all gatherings of more than 1000 people.