COVID-19 in the United States: Latest Projections

SUMMARY

I explained yesterday that I have devised a more sophisticated method of projecting the numbers of COVID-19 cases and deaths in the U.S. I had earlier projected 250,000 cases and 10,000 deaths. My new method yields higher numbers than those, but far fewer deaths than the official estimate issued by the White House: 100,000 to 240,000. My guess is that the official estimate has been inflated to scare people into staying at home, which will reduce the rate at which new cases arise and prevent the number of deaths from reaching 100,000 or more.

In any event, a day makes a difference. Yesterday, relying on data collected through April 1, I projected 870,000 cases and 40,000 deaths by the end of June. Today, with an additional day’s worth of date, the situation actually looks a bit better: 830,000 cases and 39,000 deaths. The difference isn’t significant, but the good news is that today’s estimate isn’t worse than yesterday’s. On the current projection, the fatality rate will be close to 5 percent of cases.

Figure 1 shows the projected numbers of cases and deaths by date. The curve for cases resembles a Gompertz function, which is a classic descriptor of the growth of pandemics.

Figure 1

Notes about data: I use official statistics reported by States and the District of Columbia and compiled in Template:2019–20 coronavirus pandemic data/United States medical cases at Wikipedia. The statistics exclude cases and deaths occurring among repatriated persons (i.e., Americans returned from other countries or cruise ships). The source tables include the U.S. territories of Guam, the Northern Mariana Islands, Puerto Rico, and the Virgin Islands, but I have excluded them from my analysis. I would also exclude Alaska and Hawaii, given their distance from the coterminous U.S., but it would be cumbersome to do so. Further, both States have low numbers of cases and (thus far) only 3 deaths (in Alaska and 2 in Hawaii, so leaving them in has almost no effect on my analysis.

RELATED CHARTS AND ANALYSIS

As indicated by Figure 2, the number of cases is 7/100th of 1 percent of the population of the U.S.; the number of deaths, 17/1,000th of 1 percent. Only 2.4 percent of cases have thus far resulted in deaths, but the final fatality rate will be higher (as mentioned above) because new deaths lag new cases (as discussed later). Note the logarithmic scale on the vertical axis; every major division (e.g., 0.01%) is 10 times the preceding major division (e.g., 0.001%).

Figure 2

Figure 3 shows how the coronavirus outbreak compares with earlier pandemics when the numbers for those pandemics are adjusted upward to account for population growth since their occurrence. (Again, note that the vertical axis is logarithmic.) Thus far, the number of COVID-19 cases is only 4/10th of 1 percent of the number of swine-flu cases, but the number of COVID-19 deaths has reached 45 percent of the number of swine-flu deaths. In the end, the U.S. fatality rate for the swine-flu pandemic was 2/100 of 1 percent; for the Spanish flu pandemic, 2 percent.

Figure 3

As shown in Figure 4, the daily percentage change in new cases is declining, as is the daily percentage change in new deaths.

Figure 4

However, new deaths necessarily lag new cases. As of yesterday, the best fit between new cases and new deaths is a 5-day lag (Figure 5).

Figure 5

Figure 6 shows the tighter relationship between new cases and new deaths (especially in the past two weeks) when Figure 4 is adjusted to introduce the 5-day lag.

Figure 6

Figure 7 shows the similarly tight relationship that results from the removal of the 6 “hot spots” — Connecticut, Louisiana, Massachusetts, Michigan, New Jersey, and New York — which have the highest incidence of cases per capita.

Figure 7

The good news here is the the declining rate of increase in the incidence of new cases, both nationwide (Figure 6) and in the States that have been less hard-hit by COVID-19 (Figure 7). The rest of the good news is that if the rate of new cases continues to decline, so will the rate of new deaths (though with a lag). Thus the prediction at the top of this post, which is derived by applying the lagged relationship between new deaths and new cases to the declining rate at which new cases develop, which is described by a mathematical function known as a decaying exponential.

100,000 to 240,000 COVID-19 Deaths in the U.S.?

REVISED ESTIMATES (INDICATED BY STRIKETHROUGHS) TO ADJUST FOR THE ADDITION OF DATA THROUGH APRIL 1, 2020, INCLUDING PREVIOUSLY MISSING DATA FOR THE STATE OF WASHINGTON.

Using some simple linear models of the rates of growth in U.S. coronavirus cases and deaths, I predicted that cases would top out at 250,000 and deaths wouldn’t exceed 10,000. I assumed that

lockdowns, quarantines, and social distancing continue for at least two more weeks, and assuming that there isn’t a second wave of COVID-19 because of early relaxation or re-infection.

I also said that, in any event,

the final numbers will be well below the totals for the swine-flu epidemic of 2009-10 (59 million and 12,000) but you won’t hear about it from the leftist media.

Is it time for me to back off my bold predictions, in light of the “official” estimate of 100,000 to 240,000 deaths that was announced at yesterday’s White House briefing? Probably.

First, let’s look at the numbers:

  • The Spanish flu pandemic of 1918-19 resulted in a maximum of 675,000 deaths out of 29 million U.S. cases — a fatality rate of 2.4 percent.
  • The H1N1 pandemic of 2009-10 resulted in 12,000 deaths out of 59 million U.S. cases — a fatality rate of 2/100 of one percent.
  • COVID-19 is (thus far) more lethal than the two earlier pandemics — 4.6 percent of the number of cases reached 5 days earlier. (A 5-day lag yields the strongest correlation between new cases and new deaths.)

Rounding up to 5 percent — and assuming that the rate remains constant — a total of 100,000 deaths means a total of 2 million cases, and a total of 240,000 deaths means a total of 4.8 million cases. As of today, the number of cases is somewhere above 200,000. Will the number of cases increase 10-fold to 24-fold, or more? Will the fatality rate rise?

Lacking detailed knowledge of how the official estimates are derived, I computed non-linear estimates of the rates at which new cases and new deaths will occur, based on statistics through March 31, 2020 (though numbers for Washington haven’t been posted for three days) April 1, 2020. The rate of increase in new cases declines gradually (the function is a decaying exponential) and never reaches zero, but approaches it by the end of June 2020. The rate at which new cases yield new deaths declines gradually, from a base of 5.8 6.6 percent, as the number of new cases increases (the relationship is a power function with an exponent of less than 1).

The bottom line: By July 1, 2020, the total number of cases in the U.S. will may reach 800,000 870,000, resulting in 35,000 40,000 deaths. That’s a fatality rate of about 4.3 4.6 percent per case and 1/100 12/1,000 of 1 percent of the country’s population.

Again, I assume that lockdowns, quarantines, and social distancing continue (though for how long I can’t say). I also assume that there won’t be a second wave of COVID-19 because of re-infections or an early relaxation of precautions.

Why is my revised and more sophisticated estimate of the number of deaths so much lower than the official one? It’s probably true that the official estimate simulates the spread of the contagion, whereas my general model doesn’t do that. But my guess is that the official estimate has been inflated to scare people into staying at home, which will reduce the rate at which new cases arise and prevent the number of deaths from reaching 100,000 or more.

COVID-19 in the United States

I have created several charts based on official (State-by-State) statistics on COVID-19 cases in the U.S. that are reported here. The statistics exclude cases and deaths occurring among repatriated persons (i.e., Americans returned from other countries or cruise ships).

The source tables include the U.S. territories of Guam, the Northern Mariana Islands, Puerto Rico, and the Virgin Islands, but I have excluded them from my analysis. I would also exclude Alaska and Hawaii, given their distance from the coterminous U.S., but it would be cumbersome to do so. Further, both States have low numbers of cases and (as yet) only 3 deaths (in Alaska), so leaving them in has almost no effect on the results displayed below.

All of the following charts are current through March 30, 2020. Based on statistical relationships underlying the charts, I stand by the prediction that I made on March 29, 2020:

Assuming that lockdowns, quarantines, and social distancing continue for at least two more weeks, and assuming that there isn’t a second wave of COVID-19 because of early relaxation or re-infection:

  • The total number of COVID-19 cases in the U.S. won’t exceed 250,000.
  • The total number of U.S. deaths attributed to COVID-19 won’t exceed 10,000.

In any event, the final numbers will be well below the totals for the swine-flu epidemic of 2009-10 (59 million and 12,000) but you won’t hear about it from the leftist media.

UPDATE 03/31/20: Some sources are reporting higher numbers of U.S. cases and deaths than the source that I am using for my analysis and predictions. It is therefore possible that the final numbers (according to some sources) will be higher than my predictions. But I will be in the ballpark.

UPDATE 04/01/20: See my revised estimate.

*   *   *

As indicated by Figure 1, the number of cases is about 1/20th of 1 percent of the population of the U.S.; the number of deaths, about 1/1,000th of 1 percent. Only 1.8 percent of cases have thus far resulted in deaths. Note the logarithmic scale on the vertical axis. Every major division (e.g., 0.01%) is 10 times the preceding major division (e.g., 0.001%).

Figure 1

I have seen some comparisons of the U.S. with other countries, but they use raw numbers of cases and deaths rather than cases and deaths per unit of population. The comparisons therefore make the situation in the U.S. look far worse than it really is.

Nor do the publishers of such comparisons address cross-country differences the completeness of data-collection or standards for identifying cases and deaths as resulting from COVID-19.

In any event, Figure 2 shows how the coronavirus outbreak compares with earlier pandemics when the numbers for those pandemics are adjusted upward to account for population growth since their occurrence. (Again, note that the vertical axis is logarithmic.) The number of COVID-19 cases is thus far only about 2 percent of the number of swine-flu cases; the number of COVID-19 deaths is thus far about 16 percent of the number of swine-flu deaths. So far, COVID-19 seems to kill a higher fraction of those infected than did the swine flu, but on present trends (discussed below) it may not prove to be any more lethal than the swine flu.

Figure 2

As shown in Figure 3, the daily percentage change in new cases is declining, as is the daily percentage change in new deaths.

Figure 3

However, new deaths necessarily lag new cases. As of yesterday, the best fit between new cases and new deaths is a 5-day lag (Figure 4). At the present rate, every 1,000 new cases will yield about 34 new deaths. This ratio has been declining daily, which is another bit of good news.

Figure 4

Figure 5 shows the tighter relationship between new cases and new deaths (especially in the past two weeks) when Figure 3 is adjusted to introduce the 5-day lag.

Figure 5

Figure 6 shows the similarly tight relationship that results from the removal of the 6 “hot spots” — Connecticut, the District of Columbia, Louisiana, Massachusetts, New Jersey, and New York — which have the highest incidence of cases per capita.

Figure 6

The good news here is the the declining rate of increase in the incidence of new cases, both nationwide (including the “hot spots”) and in the States that have been less hard-hit by COVID-19. The rest of the good news is that if the rate of new cases continues to decline, so will the rate of new deaths (though with a lag). Thus the prediction at the top of this post.

COVID-19 Update and Prediction

I have updated my statistical analysis here. Note especially the continued decline in the daily rate of new cases and the low rate of new deaths per new case.

Now for the prediction. Assuming that lockdowns, quarantines, and social distancing continue for at least two more weeks, and assuming that there isn’t a second wave of COVID-19 because of early relaxation or re-infection:

  • The total number of COVID-19 cases in the U.S. won’t exceed 250,000.
  • The total number of U.S. deaths attributed to COVID-19 won’t exceed 10,000.

In any event, the final numbers will be well below the totals for the swine-flu epidemic of 2009-10 (59 million and 12,000) but you won’t hear about it from the leftist media.

UPDATE 03/31/20: Some sources are reporting higher numbers of U.S. cases and deaths than the source that I am using for my analysis and predictions. It is therefore possible that the final numbers (according to some sources) will be higher than my predictions. But I will be in the ballpark.

UPDATE 04/10/20: See my revised estimate.

The Lesson from the Diamond Princess, Underscored

What I say here, Willis Eschenbach says here (in greater detail).

Related reading:

Brian C. Joondeph, M.D., “Remember the H1N1 Pandemic? I Don’t Either“, American Thinker, March 16, 2020

J.G. Walsh, “Weighing the Future: Coronavirus and the Economy“, American Thinker, March 16, 2020

Gordon Wysong, “The Coronavirus Will Save America“, American Thinker, March 16, 2020

See also my posts, “America’s Long Vac” and “Trump, the Coronavirus Panic, and the Stock Market“.

America’s Long Vac

COVID-19 has shut down much of America (and the world, too, I suppose). The shutdowns are coinciding with, extending, and preempting spring breaks at schools, colleges, and universities. You might say that America is taking a Long Vac. That’s the British term for summer vacation from school, college, or university. (See Oxford Glossary.)

How long will it last? Hard to say. Necessity rather than prevention may force the resumption of normal operations and activities. Although — and this is merely a hope — Americans will be less inclined to demand and supply products and services which are merely the excess fruits of capitalism (e.g., ocean cruises, boisterous rock concerts, destination weddings, and professional basketball).

Trump, the Coronavirus Panic, and the Stock Market

UPDATED 03/16/20

A writer at The Washington Post compiled a record of President Trump’s statements about COVID-19 through yesterday. Whether it is a complete and unbiased compilation I will leave to you to investigate and decide. Let’s just say that it doesn’t put Mr. Trump in a good light, which was undoubtedly the writer’s intention given the identity of his employer.

I say that the compilation doesn’t put the president in a good light because his optimism has been depicted as a manifestation of ignorance and stupidity. But — as was obvious to anyone with a modicum of common sense (i.e., not rabid reporters and other leftists who won’t let a crisis go to waste) — Mr. Trump was merely striving (in vain, it seems) to defuse the panic that the media and disloyal opposition have been intent on spreading.

The president’s declaration today of a national emergency would seem to be an admission that he had been unduly optimistic and glaringly wrong in his earlier statements. But that remains to be seen; as of now, the incidence of COVID-19 in the U.S. accounts for only a minute fraction of the populace (6/1,000,000), and the number of deaths accounts for an almost invisible fraction of the populace (2.2 percent of cases thus far). The cancellation of events and the widespread practice of self-quarantine and isolation will do much to reduce the incidence of COVID-19 from what it would otherwise had been. But it is still far too soon to know how bad it will get in the U.S.

According to the article in the Post, president made his first public comment about COVID-19 on January 22. The full effect of that statement, if there was any effect, would have been reflected in the Rasmussen Reports Presidential Tracking Poll of January 27. As it happens, Mr. Trump’s approval numbers didn’t vary much after that date until the week of February 24-28, when they jumped and then dived.

What happened during that week? Trump’s visit to India (which seemed to be a plus for him) was followed by a sharp drop in the stock market. Trump’s approval ratings haven’t changed much since February 28 (see the first graph below), despite (a) the spread of COVID-19 in the U.S., (b) panicky responses by opportunistic media types and Democrats, (c) a rising tide of closures and cancellations, (d) a brief recovery in stock prices followed by sharp declines (see the second graph below), and (e) today’s partial recovery in the wake of Trump’s declaration of emergency (again, see the second graph).

What does it all mean? Trump’s approval rating, it seems to me, is related directly to the state of the stock market, which is related directly to fears about the economic effects of COVID-19, which is driven by fears about the spread of COVID-19 throughout the world and in the U.S., in particular. That is to say, most voters are sensible enough to know that what the president says about the disease has next to no effect on its incidence, and therefore next to no effect on them, personally. But — out of long and misguided habit (driven by the media and the professoriate) — a large share of the electorate holds the president responsible for short-run changes in the state of the economy. The stock market reflects expectations about those changes, usually in an exaggerated way.

Sic semper boobus americanus.

I expect today’s jump in stock prices to show up in Monday’s Presidential Tracking Poll. UPDATE: Well, the Fed did it again, with another panicky (and probably ineffective) rate cut, which sent the market tumbling (though it’s recovering somewhat at this moment).

Lesson from the Diamond Princess: Panic Is Unwarranted

As of today there have been 696 reported cases of coronavirus among the 3,711 passengers who were aboard the Diamond Princess cruise ship. The ship was quarantined on February 1; all passengers and crew had disembarked by March 1. As of March 1, there were 6 deaths among those infected, and the number hasn’t grown (as of today).

Given the ease with which the virus could be transmitted on a ship, the Diamond Princess may represent an upper limit on contagion and mortality:

  • an infection rate of 19 percent of those onboard the ship
  • a fatality rate of less than 1 percent among those known to have contracted the disease
  • a fatality rate of less than 2/10 of 1 percent of the population potentially exposed to the disease.

Conclusion: There is no question that coronavirus represents a significant threat to life, health, and economic activity. But the panic being fomented by the media and opportunistic politicians is unwarranted.