Post #1070: COVID-19 updates to 3/22/2021

Posted on March 23, 2021

Vaccinated fraction of the elderly rose by 0.4 percentage points from yesterday.  That’s half the rate of the three days prior, and a third the rate of the three weeks prior to that.  I wouldn’t normally track this from day-to-day, but as I noted in Post #1064, when that stops rising, I expect it to stop fairly abruptly.

Source:  US CDC COVID data tracker.

The number of new US new COVID-19 cases per day continues to drift downward.  There’s no consistency across regions or states.  So that’s not a case of stable rates across the states, that’s a case of states with increases just by-chance offsetting states with decreases.

Source for this and subsequent graphs:  Calculated from The New York Times. (2021). Coronavirus (Covid-19) Data in the United States. Retrieved 3/23/2021, from  The NY Times on-line U.S. tracking page may be found at this link.

New York:  New cases rates are rising in nearly all Northeast states except New York.  And they appear to be rising at an oddly uniform and similar rate.  So the Northeast as a whole has a flat trend, consisting of falling new case rates in NY and rising new case rates pretty much everywhere else.

Florida:  Florida has gone from a modest downward trend to flat.  Florida, recall, is one of the states that ought to be showing the effects of the more-infectious U.K. variant.

California:  The long-standing downward trend in California may be flattening out.

Michigan.  Michigan is still a hotspot, with rising case counts.  And note that this is on a log scale, so the they are not just rising, they are rising at an increasing rate, compared to a couple of weeks ago.  Looks like Minnesota has rising counts as well.  Michigan’s increase, recall, is concentrated among high school students and young adults.

It’s worth re-posting that using a natural units (as opposed to log) scale, so you can see the upturn.  Another few days of this and Michigan will be back to where it was at the peak of the U.S. COVID third wave.

South-Central and Mountain:  Posted here just for completeness.

And just as an after thought, Canada.  The U.S. and Canadian experience was eerily parallel through roughly 3/2/2021.  (Except that they didn’t have much of a summer wave, but neither did the cool-climate states of the U.S.).  But now, the Canadian new-case rate is rising, when the U.S. new case rate is flag.

I think the natural assumption is that this is an effect of vaccination.  As of today, they have well under 2% of their population fully vaccinated, versus about 14% of the U.S. population.


So maybe having no particular trend is a good thing, in this context.