At this point HK center for health protection doesn't have travel advisories for the US.

I wonder if such a strict shut down will be helpful. How long is it maintainable, and do they expect to remain virus-free after that? E.g. they quarantine a lot of people for 2-3 weeks, no one gets sick, they return to business as usual, and boom, a sick traveller (asymptomatic at the airport) infects a few people...