Over the last two weeks (ending 2/13), the country’s epidemic metrics have plummeted at a rate none of the experts expected.

Hospitalizations

COVID hospitalizations have now dropped by almost half since the peak just five weeks ago.  Yesterday, total hospitalizations dropped below 70,000 for the first time since mid-November and if hospitalizations continue to fall at the current rate, they will be below the July peak later this week.

What is even more remarkable is that the rate of the decline is accelerating.   Last week averaged almost 3% per day.

As I suspected, the IHME model’s hospitalizations projection has proved to be overly pessimistic.  Its most recent run (February 12) projects that hospitalizations will continue to decline through March, level off in April and the begin another gradual decline in May, reaching a total of 22,000 hospitalizations by the end of May.  That still seems overly pessimistic to me.

Fatalities

As expected, average daily reported fatalities have begun to drop as hospitalizations have come down.  The seven-day moving average ended this two-week period at 2,751, down from a high of 3,211 just ten days ago.  Most likely, fatalities, based on the actual date of death, peaked sometime in early January.

Total fatality numbers for the country were skewed over this period by Ohio and New York reporting fatalities that had previously not been recorded.  The New York backlog appears to be related to the unfolding scandal in which it is alleged the Cuomo administration intentionally underreported nursing home deaths.

Vaccines

The national vaccination campaign continues at a good clip.  The average number of vaccines administered daily increased last week from 1.35 million to 1.65 million.  The CDC’s vaccine website showed that through Saturday (February 13) just under 70 million doses have been delivered to the States and various federal agencies.  Over 50 million injections have been administered and over 13 million Americans are now fully vaccinated.

The principal bottleneck at this point appears to be manufacturing constraints at Pfizer and Moderna.  I don’t think we are going to see a big increase in the vaccination numbers until Johnson & Johnson comes online toward the end of the month.

The level of vaccinations we have achieved is remarkable and unprecedented considering the genome of the virus was only sequenced fourteen months ago.  Because we did the sensible thing and vaccinated seniors first, we should really start seeing a dramatic decline in the fatalities with these vaccination numbers.

Testing

Testing continues to trend downward.  As much as public health officials would like for everyone to regularly get tested, that is not going to happen.  For the most part, people are only going to be tested if they have symptoms, think they have been exposed or are required to do so by a school or employer.  As all of those triggers become less common, testing will continue to decline.

I have expressed my opinion about testing data many times but in the “for what it’s worth category,” positive tests fell by 30% last week while testing only fell by 12%.  The positivity rate fell from 8.2% to 5.8%.  The seven-day moving average for the COVID Tracking Project’s daily “new case” metric has dropped from a high of 247,000 just one month ago to 94,000 yesterday (Feb 13).

Summary

When I look at these numbers, I am completely flummoxed by many really smart people in this field continuing to express skepticism about reaching herd immunity.  I also find myself scratching my head at the constant mantra you hear that we must vaccinate 70-80% of the population to achieve herd immunity because (1) that will never happen and (2) it completely discounts any benefit from natural immunity.

One of the most extreme views of this skepticism was recently expressed by one of the IHME’s researchers, Christopher Murray, in this article, questioning whether it will ever be possible to reach herd immunity.  He suggests that we live in a perpetual COVID epidemic, at least in the winter, requiring us to wear masks and social distance every winter – forever!  Dr. Murray seems unperturbed by the fact that there has never been a perpetual epidemic in human history.

Of course, if you do not believe in herd immunity, you have to come up with an alternative theory to explain the precipitous decline in the COVID numbers.  The two most popular theories are that we are on the backside of a holiday spike and that the various non-pharmacological interventions (NPIs) have finally broken the back of the epidemic.

The problem with these theories is that the COVID numbers peaked and began declining at the same time almost everywhere in the world, including places that do not celebrate our holidays and in countries that have mostly eschewed NPIs.  Below is a screenshot of the World Health Organization’s dashboard of weekly new cases in the six regions it uses for reporting.  It shows that in four of the six regions, cases peaked and began to decline in weeks ending January 4 or January 11.

Now, I have a lot of problems with the WHO data.  The differences in countries’ reporting methodology are dramatic and it is folly to try to compare outcomes between countries for the most part.  However, it is hard to imagine that this startling coincidence of peak infections in about three-quarters of the world’s population is the result of human behavior and not something driven by nature, or more specifically, the human immune system which has been waging war with pathogens like COVID for millennia.

Despite all the skepticism about herd immunity, I seriously doubt that Farr’s law has been repealed and I think we are beginning to see is the inevitable triumph of our immune system, bolstered by the vaccines, over COVID.