[BostonCard]

The problem, as it always has been, is that exponential growth means that setting a threshold at a particular level of virus (say, when hospitals are approaching capacity) then so long as R > 1, you will have to put in your restrictions sooner rather than later, so it is not like setting a higher threshold means your restrictions can be less strict; it just means you might have an extra week or two to institute them.  To add to the challenge, remember there is a one to two week delay between any measure you take and when you can measure its effect, so even if you think you aren't in trouble yet, you might be and just not know it.

Ultimately, restrictions should be set not based on level, but on growth rate.  If R > 1, then you need to tighten up restrictions until R < 1.  It is better with this virus to act decisively early than to have to scramble and wait and have to act in a panic later.  This means that if case levels are low but growing, you have some time to institute restrictions and test their effect and then act accordingly.  If you wait until its almost too late, then you have to scramble and don't have time to fine tune the restrictions.

And to answer your question, yes we should be instituting travel restrictions and limiting non-essential travel.  And Santa Clara county instituted a widely mocked (on this board) quarantine requirement for those traveling more than 150 miles, which, given the data, was actually pretty wise.

BC

[BostonCard]

The problem, as it always has been, is that exponential growth means that setting a threshold at a particular level of virus (say, when hospitals are approaching capacity) then so long as R > 1, you will have to put in your restrictions sooner rather than later, so it is not like setting a higher threshold means your restrictions can be less strict; it just means you might have an extra week or two to institute them.  To add to the challenge, remember there is a one to two week delay between any measure you take and when you can measure its effect, so even if you think you aren't in trouble yet, you might be and just not know it.

Ultimately, restrictions should be set not based on level, but on growth rate.  If R > 1, then you need to tighten up restrictions until R < 1.  It is better with this virus to act decisively early than to have to scramble and wait and have to act in a panic later.  This means that if case levels are low but growing, you have some time to institute restrictions and test their effect and then act accordingly.  If you wait until its almost too late, then you have to scramble and don't have time to fine tune the restrictions.

And to answer your question, yes we should be instituting travel restrictions and limiting non-essential travel.  And Santa Clara county instituted a widely mocked (on this board) quarantine requirement for those traveling more than 150 miles, which, given the data, was actually pretty wise.

BC