Post #652: Some perspective on where we stand.

Posted on April 17, 2020

 

For the moment, let’s make the happy assumption that the trend document in the last post holds.  I just want to make sure we all grasp how bizarre this situation is, why risks remain high, and why we’re going to see a lot of dithering over policy choices in the months ahead.


Normally, a pandemic moves along a “sigmoid curve” or “logistic curve”.  I described this in my brief tutorial on the math of epidemics (Post #625).  The disease “runs its course”, spreading through the population  until the natural immunity of those who have survived it breaks the chain of transmission.

So, it starts out small, spreads like wildfire at some point, then eventually stops when potential new victims become fewer and fewer.  Resulting in a sort of S-shaped curve, known as a sigmoid or logistic curve.

Several credible sources separately suggested that 60 to 70 percent of the population would eventually be infected with COVID-19, if this pandemic were to run its natural course.  Famously, German Chancellor Merkel said that 70 percent of the German population would be infected.  Estimates for the West Coast states ran in the mid-60-percents.

And so, that graph above, that’s as fairly realistic representation of what would have happened, absent drastic action on our part.  The disease would have run its course over the next few months, and finally stopped when 70 percent of the population had been infected.

But, in fact, in Virginia, even in Fairfax County, at the outside, less than one percent of the population has been infected.  You can see my calculation laid out in Post #624.  I might, given what I now know, change those assumptions a bit, in a way that would increase the total.  But nothing that would change the magnitude of the results.  At the outside, one percent of Virginians have been infected.

And that’s what leads to the graph at the top of this page.  If the trends hold, we will have been able to slow, then stop, the spread of this within Virginia.  But the rest of the sigmoid curve still looms over us.

Bottom line:  If we go back to doing what we were doing, we’ll go back to dying as we were dying.  We’ll just get back to riding up the sigmoid curve.

So anyone with an ounce of sense knows that whatever we do next, it’s not going to be a “return to normal”, in the sense of going back to the USA of 1/1/2020.  As long as even a handful of infectious cases remain out “in the wild” in Virginia, if we simply went back to our lifestyle as of 1/1/2020,  give it a couple of months, and we’ll just restart our journey up the sigmoid curve.

This is not news to people who study epidemics.  US scientists and public health officials have been saying this for months.  This is only news to people who can’t or won’t be bothered to listen to the experts.

But here’s the thing:  We’ve never been in this situation before.  Nobody has.  I’m pretty sure that the human population has never before in history stopped a pandemic.  Certainly not this early in the game.

So nobody is quite sure what to do next.  The only thing we can be sure about is that simplistic little drawing of “flatten the curve” isn’t correct.  It’s going to look a lot more like the modified version I posted about a month ago, than like that nice smooth clean ending that you see in the original “flatten the curve” illustrations.

You’re undoubtedly going to see a lot of people, starting in a few weeks, calling for dropping all of the current restrictions.  Big, bold, self-assured statements about what is right for America.  Calls to put an end to our economic suffering.

Those people are stupid.  Full stop.

The problem is, you’re going to see the smartest people in the room do a lot of dithering.  Don’t take that as a sign of weakness.  Don’t take that as a sign that they don’t know what they are doing.

Take that as an indication that they know that they don’t know what they are doing, and they are proceeding accordingly.  Nobody has ever had to deal with this before.  And the fact that a) they know what they don’t know, and b) they understand that the sigmoid curve still hangs over use — that’s what separates them from the dummies who call for an immediate return to “normal”.

Our various governments are going to have to do what seems plausible, and shift gears as required.  Some people will surely try to interpret that as a sign of weakness.  I just interpret that as an accurate reflection of reality.

Sometimes, you really don’t know what to do.  And in that case, the worst thing you can do is pretend that you do, take a course of action, and stick with it.  This is one case where the people who have no clear and bold plan are the only people who actually have a plan.