Post #1220: COVID-19 trend to 8-23-2021, still on track

Posted on August 24, 2021

Today the U.S. stands at 46.6 new COVID-19 cases per 100,000 population per day.  The seven-day rate of growth has slowed to six percent, and new cases actually fell in the South Atlantic region over the past week.  Most of the states with very high case rates are clearly peaking, most of the states with low case rates continue to see those case rates grow.

Best guess, we’re still on track for a U.S. peak in early September.

Data source for this and other graphs of new case counts:  Calculated from The New York Times. (2021). Coronavirus (Covid-19) Data in the United States. Retrieved 8/24/2021, from https://github.com/nytimes/covid-19-data.”  The NY Times U.S. tracking page may be found at https://www.nytimes.com/interactive/2020/us/coronavirus-us-cases.html.

Here’s how the actual data to date compare with my simple “sketch” projection from ten days ago.  The observed data are just a hair under the sketched-in line.

There’s still a big divide, in terms of new-case growth rate, between the states with high current rates and low current rates.  Basically, states aren’t reaching a peak until they’ve had a significant portion of the population get infected in this wave.  That is, it still looks like the pandemic simply has to “run its course”, state by state.  The low-rate states are, almost without exception, states where the Delta wave started later.

 

Actually, that’s clearer if we just slap all the states onto the same page and show the entire pandemic.  This is now starting to look like prior peaks.  As with prior peaks, the states that start the wave peak first.  Other states peak later.

There has been a further breakdown in the discipline with which states report data.  Near as I can tell, for certain states (in particular, Florida), when the numbers are good, they report them right away.  When they are bad, they wait a day or two.  This has the unfortunate effect of adding a lot of “chop” to the resulting seven-day-moving average curves.  There’s nothing systematic I can do about that.  But if you read a headline about some big new jump in cases in some state, bear in mind that some of that is going on now due to this every-shifting data reporting.  You need to let any such record age for a day or two to see if it’s real or just an artifact of reporting.

In fact, some of the most recent slowdown has that sort of look to it.  What had been a fairly smooth curve of changes in the seven-day increase took an abrupt down-turn with this last day of data.  So, plausibly, the measured six-percent growth rate might be a bit optimistic.

At this point, I seem to have run out of other ways to say that new case growth is slowing.  So let’s leave it at that.

There has been a weirdly recurrent theme with this pandemic.  Individual states get right to the point of crisis — hospital beds filled, ICUs filled, no ambulance service, because COVID-19 patients are stacked up in ambulances.

And then, at that point, somehow, the pandemic turns around.  That’s what we appear to be seeing now in the highest-new-case-rate states.

In the past, you could plausibly attribute that to governors who would not act until the hospitals were full (Post #890).  But this time, we’ve taken it one step beyond.  This time, we have Republican governors forbidding mask mandates and any other restrictions, even though they have areas where the hospitals are full.

And yet we still have not tumbled into that third-world mass-grave scenario.  I can’t quite figure out what to attribute that to.  But maybe, once the news of full ICU beds gets around, people start to take the pandemic a little more seriously.  For a while, at least.  I can’t think of any other scenario under which the pandemic is so clearly self-limiting, right at the point of total breakdown of the hospital system.

Pity that folks can’t get serious before then.  But I guess we should be glad for what we can get.

I should also note that it’s not just Americans.  I have a brother who lives in London, and he reports that, in the middle of Britain’s Delta wave, only the elderly are wearing masks in the shops.  And so Britain, which appeared to have this beaten with a combination of vaccination and COVID-19 restrictions, is now back in the middle of their own Delta wave, starting almost exactly two weeks after “freedom day”, the day on which most social restrictions were lifted.  The graphs below are Scotland and England.  They peaked weeks apart, but the resumed their upward trend on virtually the same day — two weeks after lifting most or all COVID-19 restrictions.