I think we're past the benefits of quarantining a single country at this point, especially a country like China that seems to still be hiding how bad it really is over there. But it's going to happen anyway, and you're absolutely right--this could be a horrible thing for economies.

In any case, in 1918 they had soldiers traveling around the world, and in 2020 they've got everybody traveling around the world--a hundred years ago travel was rare by individuals outside of the military. If they don't come up with a vaccine for this, I think we're in for a big double whammy of widespread sickness, and damaged economies. Oh, fun.