Over the last two weeks (ending March 27), all COVID metrics continued to fall, but in the second week there were distinct indications that the level of infections is plateauing. However, Americans are getting vaccinated at a torrid pace.

Hospitalizations

According to the CDC’s data, hospitalizations over the last two weeks only declined by only 3% (33,396→32,357) and new admissions actually ticked up slightly.

As I have previously shared, I think these metrics are the best indication of the current spread of serious disease.

Fatalities

Fatalities continued to fall but also at a somewhat slower pace.   Over the last two weeks, the seven-day moving average for daily reported fatalities fell by 20%, (1,248→1,011), however most of that improvement was in the first week.  This is the lowest the seven-day moving average for fatalities has been since early November.  Because fatalities are a lagging indicator, we have probably not see the full impact from the widespread vaccination of seniors yet.

IHME model’s base case is now projecting about 140 daily reported fatalities by the end of June.  Its “worst case” scenario has fatalities going back up to about 1,500 per day by mid-May and declining back down to about 1,000 by the end of June.  The 538 ensemble of about 30 models shows that fatalities will continue to gradually decrease over the next four weeks.

Vaccines

The national vaccination campaign is nothing short of  a miracle.  The U.S. averaged administering 2.7 million doses per day over the last two weeks.  As of Saturday, over 15% of the total US population and 20% of the over-18 population had been fully vaccinated.  More importantly and astonishingly, 72.4% of the over-65 population had received at least one dose and 48.4% are now fully vaccinated.  That is up from just 34.4% two weeks ago.

The vaccination program has been an amazing national effort to which hundreds of thousands of researchers, healthcare professionals and volunteers have contributed.  Don’t tell me this country is not capable of doing great things anymore, because you are seeing one right before your eyes.

Testing

The seven-day average for the CDC’s daily “new case” count fell from about 65,000 to 60,000 over the last two weeks.  But it fell to 55,000 in the first week and then bounced back.  The calculated positivity rate over the two weeks was below 5% for the first time since last fall.  I have repeated my warning about the significant limitations to the testing/new case metric in the note below.1

Summary

The flattening of the decline in the last week has raised concerns over whether this is the beginning of a third wave, as some of the COVID doom merchants have warned.  However, none of the models are predicting a large new wave and the math is making it increasingly difficult for the virus to pull one off.

At this point, something close 50% of Americans have some natural immunity to COVID and 15% have been vaccinated.  We also know that some percentage of the population is not susceptible to the disease.  No one knows what that percentage is, but some researchers have estimated it as high as 20%.  If that is the case, then only 15% of the US population is vulnerable to a third wave.  And with the current rate of vaccinations that susceptible pool is falling by about 2-4% per week, depending on how many people getting vaccinated already have natural immunity.  In other words, we are simply running out of people to get sick.

But even if there is a surge in new infections, it is even more unlikely to drive a high level of hospitalizations or fatalities.  Seniors have overwhelmingly made up the serious COVID cases.  When you add those with some natural immunity to the three-quarters of the senior population with, at least, one vaccine dose, the number of vulnerable targets for the virus really starts drying up.

The math would indicate that the only possible scenario which could cause a large third wave is a variant that almost entirely escapes the pre-existing immunity.  So far, there is scant evidence of that.  Currently, BNO’s reinfection tracker has only logged less than a hundred confirmed reinfections and about 16,000 suspected reinfections – that is out of the world’s 126 million confirmed COVID cases.  There unquestionably have been more reinfections than those registered on the BNO site, but for immunity escape to drive a major third wave we would need to be seeing millions of reinfections.

My guess is that  we might have another week or two that the decline in the metrics continue to show some plateauing.  But after we get another 20 million or so people vaccinated, I suspect we are going to start seeing this beast to really brought to heel.

Note 1 – The CDC reports “new cases” as opposed actual testing results.  There are a lot of problems with the new case metric.  First, we know that testing only discovers a portion of the actual infections and that portion has changed over time.  The PCR tests return many false positive and negative results and there continue to be delays in testing reports coming in.  As a result, every day there are “new cases” being reported where the tests occurred days or even weeks before, as we saw with Missouri reporting 80,000 old cases on March 8.  Texas reports hundreds of older cases each day and is one of the few states that segregated them in their notes.  Also, like hospitalizations, some jurisdictions only report confirmed cases as opposed to suspected cases.  As a result, the new case metric should only be used in the most general sense and little inference should be drawn from daily fluctuations.