Now 21 new cases per 100K per day, up from 20.4 yesterday. Still rising about 25 percent per week.
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 5/7/2022, 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
Maine is now over 60, Rhode Island is nearing that, and a couple of other New England states are now in the 50+ range. OTOH, there are still 15 states with fewer than 10 new case per 100K per day. With the exception of Georgia and Alabama, those are all in the central part of the country.
And now for something completely different
In the U.S., we can take some lessons from Great Britain’s second Omicron wave (BA.2.12.1 wave), which appears to be ending on its own, with no intervention from the government.
Source: Johns Hopkins data via Google search.
I say “appears to be” because the official counts of positive tests stopped tracking the new case counts in Great Britain a couple of months ago (See Post #1478 ). There remains an astonishingly large gap between the count of new infections, based on test results, and a separate estimate based on tests applied to a random sample of U.K. residents.
The random-sample testing says that about 3 percent of the entire adult population of England had an active COVID-19 infection last week:
Source: U.K. Office of National Statistics, accessed 5/7/2022.
To be clear, if I take the estimated 23 /100K / day above, multiply by seven to get a week’s worth of new positive tests, that translates to 0.16% of the U.K. population. This, compared to the estimate from the random sample of 2.91% of the population. At face value, that means that the actual number of actively infected individuals in the U.K. is 18 times higher than what the official count of positive tests shows. That gap is now about twice as large as when I looked at it one month ago (Post #1478).
I still can’t quite get all that information to line up sensibly.
It’s clear that the survey-based results track the rate of hospitalizations far better than the count of new positive test results. Here you can see the survey-based results for England, top, and the rate of hospitalizations, bottom. They are on different time scales, but a pattern of two-equal-humps clearly shows in both:
Sources: England count of positives from U.K. ONS cited above, U.K. hospitalizations are Johns Hopkins data via Google search.
By and large, what this appears to be showing is the slow decline in the use of official testing sources in Great Britain. Hence, the apparent slow fade-away of this wave, in the first graph in this section, is mainly the result in a change in propensity to get tested via some officially-recorded source. Which, in turn, might have to do with the demise of free testing in the U.K.
The case hospitalization rate is another way to understand how low the official count of new positive tests is. (That’s the fraction of new COVID-19 cases that end up being hospitalized.) The graph above shows about 11,500 residents of the U.K. currently in the hospital with COVID-19. Assuming their average length of stay is roughly what it is in the U.S., divide by 6 or so to arrive at (roughly) 2000 new COVID-19 hospitalizations per day. But if we take the U.K. new positive test rate at face value (about 15,000 per day), that would imply a case hospitalization rate of 2000/15000 = 13%? That’s not credible, in a country where the case hospitalization rate has always been well below that of the U.S. (currently about 3.5%, based on positive tests and new hospitalizations reported on the CDC COVID data tracker today).
Instead, if we estimate that the true new case rate is 18x the official count of positive tests, we arrive at a case hospitalization rate of (2000 / (15000 x 18) = 0.7%, or about one-fifth the U.S. rate. (Note that the denominator includes a large number of asymptomatic infections that would almost never be counted under any U.S. estimate). That’s far more in-line with the historical relationship between the U.K. and U.S. case hospitalization rates.
The first lesson from the U.K. is to keep your eye on the hospitalizations, in addition to any official count of positive tests. Of late, hospitalizations tended to track the true (survey-based) rate far more closely than the count of new positive tests.
The second lesson from the U.K. is that this wave is ending all on its own, with no help from the U.K. government. Which is good, because I would expect that the majority of states, and likely the Federal government, are going to take no further action on COVID-19. We’ll get over this wave when it has run its course, and not before.
And so, once again, we have to appeal to the oddly self-limiting nature of these waves of COVID-19. Each wave appears to seek out a certain fraction of the population, and then peter out well before it ought to under a classical model of an epidemic. That is, the wave stops even though the population as a whole has not approached herd immunity. (In fact, given the estimated infectiousness of Omicron, and estimated effectiveness of vaccines, herd immunity is no longer mathematically possible — which is, in part, why you never even hear the term any more.)
The bottom line is that we’re in yet another new wave of COVID-19 infections. This one is once again being driven by the emergence of a yet-more-infectious strain of COVID, one that is yet-better at evading the body’s immune systems.
But unlike prior waves, full vaccination and booster provide only modest protection against any infection. But they still provide considerable protection against severe infection — against hospitalization and death, once infected.
And that’s good, because in all likelihood, this wave is going to continue until it decides to stop. We can hope that will be sooner rather than later. But at this point, here and in other countries, it looks like the position of the government and the people is que sera sera. All the citizens can do now is wait for this one to run its course.
