Over the last two weeks (ending 1/30), the country’s epidemic metrics showed clear indications that we are on the backside of a classic bell curve as predicted by Farr’s Law.

Hospitalizations

After three months of steadily rising, hospitalizations, ICU bed usage and ventilated patients all turned down dramatically over the last two weeks.  All three declined by approximately 20% and that is on top of declines in the second week of January.  Hospitalizations have now declined for 18 consecutive days and are down 25% from the peak on January 6.

We are still well above the previous peaks in the spring and summer but note the steepness of this decline compared with the previous peaks.   If this rate of decline continues, we will be below the previous peaks within 2-3 weeks.

The most recent IHME model, which has been updated to include a parameter for the new variants, is showing a much more gradual decline in hospitalizations than we are currently seeing.  It is projecting that we will not get back below the current previous peaks until the third week in March and will still have about 40,000 hospitalizations on May 1.  That seems overly pessimistic to me.

Fatalities

Average daily reported fatalities continue to grind on at very high levels, declining only slightly from 3,209 to 3,090.  The chart shows a decrease for a few days in early in January but it is pretty clear that was due to reporting delays around the holidays.

The IHME model now shows that fatalities peaked in mid-January at about 3,200, which is earlier and at a lower level than its previous run.  However, it is now showing a more gradual decline, to just under 1,000 on May 1.  The model’s more gradual decline results in more total fatalities than it predicted earlier.  It now pegs total fatalities at just under 600,000 by May 1.  This more pessimistic view also appears to be the result of the model’s inclusion of the new parameter for the variants.

Vaccines

The national vaccination campaign continues to ramp up.  The CDC’s vaccine website showed that through Saturday (Jan 30), just under 50 million of the vaccine doses had been distributed to the States and various federal agencies.  Just under 30 million injections have been administered and 5.2 million Americans are now fully vaccinated.  For the last 3 days, we have been averaging over 1.6 million injections per day.

Johnson & Johnson also announced the results of its Phase III trial of its COVID vaccine this week and that it plans to apply for emergency use authorization this week.  The J&J vaccine is a single dose and can be stored in a regular refrigerator.  Also, J&J has enormous manufacturing capability.  The inclusion of this new vaccine will greatly boost the vaccine campaign here and around the world.

Notwithstanding all the grousing over problems with the vaccine rollout, this is a remarkable accomplishment considering that we have never even had a vaccine approved in less than four years previously.  For all of Trump’s jabberwocky about COVID, Operation Warp Speed is the one thing that he got right and will significantly reduce the number of people that ultimately succumb to the virus.

Testing

Testing held steady for the last two weeks but the number of positive test results were down by 30% and the ratio of tests coming back with a positive result fell dramatically from 12.3% to 8.65%.  The seven-day average for the COVID Tracking Project’s “new cases” peaked on January 11 and has declined almost 40% since then.  I am guessing you have not seen that reported in the media.

Interestingly, the IHME model run before the holidays showed that infections would peak right around Christmas.  Its first run after the holidays moved peak infections back to mid-January but the most recent run has returned the peak to late December.

Summary

Were it not for the new COVID variants, it would be reasonable to assume that we would see the steep decline in the U.S. epidemic over the next several months as predicted by Farr’s law.  However, due to the IHME model incorporating a parameter for the variants, it is now predicting a more gradual decline.  The 538 model aggregation is not showing that the variants will have as much of an impact as the IHME model.

I am skeptical about IHME’s, and the general media narrative, that the variants are going to have a significant effect on the course of the epidemic primarily because we are seeing a similar case declines in the U.K., South Africa and Brazil, where the variants has been circulating for some time..  I suspect that we are going to find that variants were in the U.S. some time ago and likely significantly contributed to the recent surge.  Another reason I think this may be the case is because the popular narrative that the recent surge was caused by holiday gatherings and colder weather is really not supported by the data.  There were many parts of the country where it was quite cold over the holidays but nonetheless saw quite dramatic declines during that time.

Also, the reduction in the efficacy of the vaccines against the new variants has been largely misinterpreted. The headline number, i.e., the efficacy in preventing any infection, is not the significant number.  The efficacy in preventing serious disease, as in hospitalization or death, is what we really care about and that has been close to 100% with all of the vaccines.  If there is community spread that is not causing serious disease, we will likely not even detect it because testing resulting from symptomatic infections will decline.  And finally we have very little data on how effective naturally acquired immunity will be against the new variants. One immunologist I spoke to said that it is possible that a natural infection sets off a more broadly based immune response that may provide better protection against the variants. Certainly, we still have very few documented cases of reinfection.

In any event, the course of the epidemic over the next several weeks should prove or disprove the significance of the variants.  But Farr’s Law it appears that once again being proven to be accurate.  I think we are really only looking at the question whether the decline going to be rapid or gradual.