San Francisco is going the way of Italy with its coronavirus safety measures -- the Mayor's instituting around-the-clock curfew, banning almost everyone from leaving their homes.

Mayor London Breed announced what she calls a "defining moment" in U.S. response to the pandemic. Beginning at 12 AM, all residents within the city can only leave home for doctor's appointments or runs to the grocery store.

It's the strictest new policy enacted in the nation, and matches the current rules in Italy ... which has been the 2nd hardest-hit country in the world.

The Mayor says the rule will remain in effect for at least the next 3 weeks.

In addition, to the city shut down, 6 Bay Area counties are telling residents to "shelter in place." That means ... unless your work falls under the list of "essential businesses," you've been ordered to stay home.