Post #1383: COVID-19 update to 1/3/2021

Posted on January 4, 2022

 

The U.S. is now up to at least 151 new COVID-19 cases per 100K population per day. 

About a half-dozen states did not report new data today, including, most critically, Florida.  If I gap-fill all of those with my projections from yesterday, I would estimate 160 new cases / 100K / day for today’s true count.  So there’s a bit more bad news that will come out later in the week as those states finally get around to reporting new data.

Omicron is now putting more people into the hospital than Delta did.  I’m still figuring that, at best, Omicron has one-third the case hospitalization rate of Delta.  And we’re now more than three times the new case rate at the peak of the Delta wave.  So it’s no surprise that Omicron’s hospitalizations are now above the peak of Delta’s.

Evidence still suggests a lower ICU use, when hospitalized, so we may or may not overrun hospital ICU capacity in many places.  And the jury is still out on case mortality rate, but the lower ICU use pretty strongly suggests that we’ll see a lower case mortality rate as well.

Are there any rays of light?  Maybe.  New York and DC led the way up.  Both appear to be topping out.  It’s a bit too early to say for sure.  But both had a few days with no net growth in new cases.  Maybe they’ve topped out, maybe they’ve just run out of testing capacity.  I should also note that, nationally, even after non-reporting adjustment, we came in below my constant-growth projection of 180 new cases (Post #1382).  So something slowed down, at least a bit, between a few days ago, and today.

Now for the pictures.


Case counts

I’m not even going to note where I have rescaled my graphs this time around.  Suffice it to say that as the lines get taller, I have to keep bumping up the limits on the Y-axes.

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 1/4/2022, 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.

Above, that’s where we stand as of yesterday.  New infections more-or-less doubled over the past week.  The Northeast continues to lead the way, and is still the hardest-hit region in this wave.  All regions of the country are now near or above 100 new cases per 100K per day.  The vast majority of states (35) now exceed 100 new cases / 100K / day.

(The kinks in the lines above are an artifact of data reporting.  When states don’t report, I hold them at their most-recent level until fresh data arrives.  That’s why you see all those nearly-level segments toward the end of the line..  The end of the line ends up in the right place, but the path in getting to the end of the line has a kink in it.)

Taking a longer perspective, the daily new case rate is now three times what it was at the peak of the Delta wave.

Really, the only bright spots today are New York and Washington DC.  Those have been the leaders in this so far, and both of them failed to show increases over the past few days.  Maybe they’ve started to top out.  Maybe they’ve just run out of testing capacity.  It’s too soon to tell.  (The DC number looks like a data reporting artifact, but they did in fact report data today.  It’s just that the three-day total came in at almost exactly the rate they were showing before.)

A final bit of evidence suggesting that these may be true peaks is that new COVID-19 hospitalizations also peaked in both states.  DC peaked on 12/29/2021, NY peaked on 12/30/2021.  That suggests that these flat spots in the new case counts are real, and not just an artifact of running out of testing capacity.  (That’s from the U.S. DHHS unified hospital dataset, below.)


Hospital data

Throughout this section, the data source is the Federal unified hospital dataset, daily summary at the state level, available at this link.

Under-reporting adjustment.  It’s pretty clear that there is some consistent under-reporting for the most recent day or two of each new release of the file.  For this round, I’ve tried to adjust those numbers up, based on the historical levels of under-reporting seen as of last week.  (In other words, I compared some old “raw” numbers to the final numbers, figured out how much the last couple of days of raw data tended to be short, and inflated the current “raw” numbers by that much.)

As of 1/3/2021, we’re seeing almost as many daily COVID-19 hospital admissions as we saw at the peak of last year’s winter wave.  We’re seeing more than we saw at the peak of the Delta wave.  (And recall, these are seven-day moving averages, so the actual raw count for today, in isolation, is considerably higher than what it shown.  Arguably, we’re already well above all prior peaks in daily COVID-19 hospitalizations.)

Source:  Calculated from Federal unified hospital dataset, daily summary at the state level, available at this link. 

Separately, we can also tabulate the number of Adult COVID-19 confirmed cases  in the hospital, and in the ICU.   The interesting thing here is that as the case mix shifts from Delta patients to Omicron patients, a lower share of them end up in the ICU.  That’s a bit of an exaggeration, toward the end of the line, as it may take few days for persons admitted to enter the ICU.  But even going back a week, the ICU line has a lower slope than the total patients line.

We can also probably infer that average length of stay is falling, because even though we are admitting more cases each day, compared to Delta (blue line, above) we actually have fewer people in the hospital at any one time.  That can only occur if they are getting out of the hospital faster.  That, too, may be somewhat exaggerated at the every end of the line, due to the rapid upward trend in new admissions.

Source:  Calculated from Federal unified hospital dataset, daily summary at the state level, available at this link. 

In terms of hospital system stress, then, we’re not quite at the levels achieved in prior peaks (at least, for the U.S. as a whole).  It appears that COVID-19 patients are occupying about 20% of all staffed acute-care beds, and maybe 25% of all staffed ICU beds.   The COVID-19 fraction of acute-care beds is about as high as it has ever been, but the fraction of ICU beds is still below prior peaks.

Source:  Calculated from Federal unified hospital dataset, daily summary at the state level, available at this link. 

These last two graphs may differ due to changes in staffed beds.  One aspect of Omicron is that so many people are being infected, it’s causing hospital staff shortages.  (That, and burnout, and you name it.)

This last graph is not quantitative, in that it’s just a count of hospitals that report having a critical shortage of staffing.  So, here, a 25 bed rural hospital counts the same as a 1000 bed urban teaching hospital.

Source:  Calculated from Federal unified hospital dataset, daily summary at the state level, available at this link. 

Based on that measure, U.S. hospitals are only slightly more stressed under Omicron than they were under Delta.  And so, while Omicrons’ impact on staffing has gotten a lot of press, it doesn’t seem to have resulted in a substantial uptick in hospitals reporting a critical shortage of staff.