Friday, April 3, 2020

Projecting Deaths from Covid-19


In my blog on Covid-19 last week (here), I suggested we could use rates of reported cases per million of population to standardize numbers across countries and gauge the trajectory of infections based on those under the gun for a longer period. Thursday, April 2, we recorded the one-millionth case, and the official death toll crossed 50,000. That day alone the world recorded nearly 6,000 deaths and almost 80,000 new cases.

Graph: Covid-19 Reported Cases per Million Population

 The chart above is an update of the one I prepared last week. It shows the growth in cases per million for Italy, Germany, and the U.S. During the week, Italy’s rate has moderated. Germany, reaping the benefits of significant early testing, has dropped below the rate experienced by Italy at the same equivalent period. The only positive spin for the U.S. is that it could be worse; we could track Spain (see below).

Same chart with Spain added


What can we learn from Germany and Spain?

Let me be clear: I don’t know what’s going on. I am speculating based on news stories and reported statistics. The number of reported cases per million of population became significant for Germany about a week after Italy (and at the same time as Spain). Germany reacted by shutting down sports and other large gatherings and instituted widespread testing. Spain allowed a rally of 120,000 people in Madrid to celebrate Women’s Day on March 8[i] (Day 3 on the above chart).

While the huge gatherings in Spain had an effect, the biggest difference was the speed in which testing rolled out. Spain, like the U.S. required central approval before administering a test. Germany’s s decentralized system experienced no such roadblocks. The result is Germany tested sooner and more widely, identifying a larger percentage of the infected earlier in their infection. This allowed for quicker quarantining of the infected, reducing exposure.

There are also cultural differences between Germans and Spaniards. Germans have a strong form of government and tend to be rule-followers. That’s not the case in Spain, whose central government let a week or more go by before they imposed the same social distancing requirements as Germany. Spaniards did not take the matter seriously until people started dying in large numbers. By then it was too late to stop the first acceleration of cases we see illustrated in the graph above.

With a country-wide lockdown enforced by police with roadblocks and drones, and nationalization of private hospitals, Spain has clamped down. Its trajectory will eventually decrease, but the delay will cost tens of thousands of lives.

What of the U.S.? Are they just trying to scare us with the projections of 100,000 to 240,000 U.S. dead?

Compared to Germany and Spain, the U.S. had an additional week’s time to prepare for the Covid-19 onslaught. Our federal government pissed it away, leaders convincing themselves that we had taken all the measures we needed by shutting our borders to those arriving from infected areas of China.

Unlike Germany, where the federal government acted deliberately, our federal government has been reluctant to exert control, leaving it up to states and municipalities to respond as they see fit. This has led to a rolling set of policies that react to local conditions after the problem has already grown large. That’s too late to dampen the curve quickly. Even today, when the positive effects of social distancing are understood, states like Florida still allow church services, which they deem essential services[ii].

This nonuniform response will continue to lead to rising case numbers. The same Florida governor who refused to close beaches during Spring Break issued a requirement for those travelling from New York to self-quarantine for fourteen days,[iii] as though the virus weren’t already spreading in his state.

So yes, given the spectacularly slow response by many state and local governments, I suspect health officials are trying to scare us into complying with requests/demands to stay at home. We’re doing much better than Spain, but not nearly as well as Germany. As it stands now, we’re not even matching Italy.

But isn’t the death rate for Covid-19 under 1%?

Does that mean we’ll have 10 to 25 million people infected? Later today, I project, we’ll exceed a quarter of a million people reported infected in the U.S. With all the social distancing ten million or twenty-five million seems unlikely in the near term. It’s unclear what assumptions the studies used to arrive at their death figures.[iv] Much depends on the duration covered, policies employed (and followed), and the death rates assumed.

The studies that showed death rates below 1% were based on data from China, which has come under question based in part on the number of urns being shipped to Wuhan province.[v] [vi]

What we do and don’t know about death rates.

The only way to know the mortality rate for a disease is to test everyone to determine who had the disease and divide that number into those who died from the disease. In fact, we’ll never know the factual answer. Some very smart people with sophisticated models will make their best estimates, which is where the 100,000 to 240,000 deaths came from.

What we know as of April 2, 2020

Excluding China, there have been 49,848 reported deaths and 933,344 reported cases of Covid-19. That’s a death rate of 5.3%. That’s low, because even if there were no more reported cases, we still expect more of those already infected to die.

An early study showed that on average two weeks passed between onset of first symptom and death. For a SWAG (some wild-assed guess), let’s assume the average reported case occurs seven days after the first symptom. If the 14-day period from first symptom to death holds up, then reported deaths came from the population whose illnesses were reported before March 26. Again removing China from the reported cases, that leaves nearly 50,000 worldwide deaths arising from 390,000 reported cases. That ratio is 12.8%!

Is that possible? Italy’s current death rate is 12.07% of reported cases. Spain, which started a week later than Italy, is already up to 9.2%.

But Germany has a 1.3%. rate. The lower rate is because the denominator includes many “healthy” sick discovered as part of Germany’s more extensive testing. Most of these additional individuals will recover (lowering the mortality rate compared to countries who didn’t know these types of individuals were ill).

Our testing rates are more comparable to Italy than to Germany, and so of those already reported, we should expect a higher mortality. (We’re already reached 2.5% and it’s climbing.) For us, experiencing 100,000 deaths may result from as few as one million reported cases—and we have already reached 250,000 cases.

It’s up to each of us.

Our previous actions, or lack thereof, have baked in the number of cases of Covid-19 the U.S. will experience over the next week to two weeks. What happens after mid-April depends on how each of us acts. Will you be responsible, or will your behavior kill others?

Your choice.
* * * * *


James M. Jackson authors the Seamus McCree series. Full of mystery and suspense, these thrillers explore financial crimes, family relationships, and what happens when they mix. False Bottom, the sixth and most recent novel in the series is set in the Boston area. You can sign up for his newsletter and find more information about Jim and his books at https://jamesmjackson.com.

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