Post #1161: COVID-19 trend to 6/17/2021, where’s Delta?

Posted on June 18, 2021

The overall trend of new COVID-19 cases continues downward for the U.S. Whatever impact the new Delta COVID-19 variant is having, it’s not large enough (yet) to offset the pre-existing trend.

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 6/18/2021, from”  The NY Times U.S. tracking page may be found at

As I was updating my graphs, I noticed that one state stands out for having a strong upward trend in new cases:  Missouri.  That’s quite the outlier, given that every other state in that region shows a fairly consistent downward trend.  

That also rang a bell.  The last time the CDC published data on incidence of variants by state,Missouri stood at the top of the list for incidence of the Delta variant. 

Source:  CDC COVID data tracker.

There are a few caveats for the table above.  First, those data are based on a small sample and so likely have a lot of uncertainty in the estimated incidence rate.  Second, that’s ancient history.  The average date for those sequenced samples would be the first week of May.  Given the less-than-two-week doubling time of incidence of the Delta variant, the incidence now should be maybe 6 times higher than what is shown.

I then searched systematically for all the states with strong and consistent upward trends.  In particular, I looked for states that had both one-week and two-week trends in excess of a 20% increase in cases per week.  Only two other states met that criterion, other than Missouri.  And, again, somewhat oddly, they were geographically clustered.  A handful of other states had smaller or less consistent upward trends.  But only these three had a strong and consistent upward trend for both of the past two weeks:

Then I read the news, and found that there’s a COVID-19 outbreak in Southwest Missouri that is being attributed to the Delta variant.

The reporting is not quite deja vu all over again.  Sure, hospitals are filling up, emergency departments are overloaded, and so on.  That’s familiar.  But this time, we have a vaccine, the patients are almost entirely un-vaccinated individuals.  In the words of a local hospital administrator in that area, what you you waiting for?

“Bed capacity is strained. ED waits are long. COVID patients are younger, sicker and unvaccinated. Vaccines are free, available and effective. What are you waiting for? 82? 102? 152? What about 1? 1 person you care about? You?”

Source:  Saint Louis Post Dispatch., emphasis mine.

Based on that reporting, Delta is now my far the most prevalent variant of the virus in Southwest Missouri.  The virus doesn’t respect state boundaries.  It doesn’t take much of an imagination to connect Southwest Missouri to states south and west of Missouri, per the map above.

Maybe this will be an isolated outbreak.  Or maybe its a harbinger for the U.S. fifth wave of COVID-19.

Before this U.S. outbreak, the only information to guide a prediction came from Great Britain.  The recent uptick in cases in Great Britain has been attributed to the spread of Delta, despite an ongoing partial lockdown.

But now we have the example of southwest Missouri.  The high incidence of Delta in Missouri was known more than a month ago.  It’s now the dominant strain in southwest Missouri.  And there’s a fresh COVID-19 outbreak there attributed to that variant that is now straining the capacity of the local hospital system.

One thing we can be sure of:  If we have another COVID-19 wave of any consequence, we’ll owe it entirely to the dumbasses who won’t get vaccinated.  Right now, vaccinated individuals account for 53 percent of the U.S. population, but only one to two percent of the U.S. COVID-19 hospitalized population (reference 1, reference 2).  More-or-less, vaccination appears to confer a fifty-fold reduction in the odds of being hospitalized with COVID-19.  The vaccines are that effective at preventing severe illness.

Source:  CDC COVID data tracker.

The trend of vaccinations picked up a bit in the past two weeks.  We’re still vaccinating at a rate in excess of 1 million doses per day.

We can quantify the degree of vaccine slacking in the US by measuring the number of doses that could have been given, if we’d kept up the highest demonstrated pace.  As illustrated below, that works out to an average of 1.5 million doses not administered for the past 60 days, or another 90 million doses that could have been given, but weren’t due to lack of demand.

The 53 percent of the population vaccinated could have been, in theory, 80%, if we had merely kept up the pace.  Just something to bear in mind of we end up with a Delta-drive fifth wave.


With these reasonably effective vaccines, we’re no longer at the mercy of the virus.  Instead, we’re at the mercy of the intelligence and public-spiritedness of our fellow citizens.  You’d hope we’d be coming ahead for that change, wouldn’t you?