Post #1223: COVID-19 trend to 8-25-2021

Posted on August 26, 2021

The U.S. now stands at 47.6 new cases / 100K / day, and weekly growth remains steady at 9%.  Still on track for an early September peak.

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 8/26/2021, from”  The NY Times U.S. tracking page may be found at

Has behavior changed in the states with high new-case rates?

We still have just three states with more than 100 new COVID-19 cases per 100,000 population per day.  Those all appear to have stabilized, if not peaked.

Did people change their habits in those states, in light of the big uptick in cases?  Or did they just proceed with business-as-usual?  Let me do a quick and casual comparison between those three states and the U.S. average, on vaccinations, mask use, and similar measures of COVID-19 related behavior.

Vaccination data can be read right off the CDC COVID-19 data tracker, but to get all the information one graph, it’s easier to download the data itself from CDC.  In this case, I’ll go with the count of shots by report date, because that’s the only series that is current through today.  (The others all have some sort of lag built in that makes them appear to tail off as we get close to the current day.)  Below, I’ve chosen to norm everything to the June 2021 daily rate, because the Delta wave started at the end of June.

Source:  Calculated from CDC data as cited above.

Well, two out of three ain’t bad.  Putting aside an obvious data glitch in there, vaccination rates climbed in Louisiana and Mississippi.  But not in Florida.  Florida’s change in daily vaccinations is not materially different from the U.S. as a whole.  Acknowledging that it’s too late for a vaccination to do you any good in the current (Delta) wave, popular press reporting says that vaccination rates pick up once the news stories about full hospitals start circulating.  But apparently that’s not true in Florida.

For mask use, all three states re-adopted masks at a faster rate than the rest of the country.  Florida is again the laggard among the three high-COVID-19 states.  By contrast, Louisiana is almost back to the level of mask use it had at the end of the prior waves.

Source:  Data from Carnegie-Mellon COVIDcast.

For indoor restaurant use (which is also a good proxy for bar visits), all three states saw larger declines than the U.S. as a whole.  In hindsight, I wonder if this is driven more by climate and social norms than by a conscious decision to avoid indoor dining due to COVID-19 risk.  Tough to say.

Source:  Data from Carnegie-Mellon COVIDcast.

I think we can conclude that there has been some modest behavioral response by those populations.  Compared to the U.S. as a whole, vaccination rates are up in two of three states.  Mask use is up somewhat to significantly in all three.  Indoor restaurant dining is down in all three.