COVID-19 excess mortality, more Defoe, and mortality good news
Preparing the space... more deaaaaath posts to come
To understand the meaning of all the deaths in Italy, it would be extraordinarily helpful to know one figure that I’ve never seen discussed: the number of excess deaths; that is, the number over and above what is usual this time of year in Italy.
I have no doubt the number is higher than usual and that there are excess deaths, particularly in certain regions of the north where the virus has been concentrated. But how much higher? Italy ordinarily has a particularly high rate of death from the flu, which makes the “excess death” figure especially important to know. Are significant numbers of the deaths we’re seeing in Italy deaths that would be taking place anyway from the flu or other illnesses we’re accustomed to? And if so, how many?
Neo links to a study about Italian experience with flu-related mortality… and it’s really high compared to other European countries.
Italy showed a higher influenza attributable excess mortality compared to other European countries. especially in the elderly.
In terms of amplitude of the at risk population, in Italy there are 6.7 million of people aged 75+ (more than 10% of the population) that constitute a large group of fragile subjects, among which the annual death rate is naturally high, around 4% (ISTAT, 2018b). Among them, a large variation in the absolute number of deaths causes small fluctuations in the mortality rate. Excess deaths constitute a serious public health issue that can be prevented coupling influenza vaccination with personal protection measures (ECDC, 2019).
I added the emphasis.
I will be coming back to that at the end.
But First: 17th Century Plague!
Some remarks on Daniel Defoe’s A Journal of the Plague Year:
While there is a specific plague being described, which I believe to be a continuation of the Black Death that hit 300+ years before, the important part is to hear about how people behaved. While our technology and medicine has progressed in 350 years, the kinds of responses to serious epidemics remains the same. Defoe especially points out how people get out of quarantine and how disease is spread well before people know they're infected.
The great thing is that Defoe brings it alive, shows in various ways that public policy does or does not work (he did have some good things to say about the actions of the Lord Mayor and Aldermen), and -- here is the important part -- what short memories people display in their behavior.
I read the book at the beginning of February, at which point the problem seemed to be mainly in China.
Take Good News Where You Can Find It
Megan McArdle asked about death trends in a recession, and I remember something about the last one.
I did find the historical stats, but the graph they’ve got is too busy.
Here is a graph of the raw numbers of traffic deaths in the U.S. by year:
Every precipitous drop in number of motor vehicle deaths was a disruption in the U.S. economy. There is the take-off in deaths from 1899 to 1928, as motor vehicles were increasing in use. The stock market crash in 1929 led to a short-term drop, and then the next large drop was due to World War II.
Since the peak of motor vehicle deaths in 1972 (54.6 thousand deaths that year), every single drastic drop has been driven by a recession.
None of those decreases were due to safety improvements, as we usually measure motor vehicle deaths in two separate metrics: number of deaths per base population and number of deaths per million of miles driven. The second metric is actually more important as the number of miles driven is more variable than population size, as population has been growing throughout this history. The number of miles driven drop drastically in recessions, and grows during economic expansion.
And the number of miles driven drops drastically when everybody is forced to stay home.
In the 2008-2009 recession, we saw double-digit percentage drops in deaths. About a 10% per year drop in deaths, which is a huge movement.
I will be looking at potential mortality results for 2020 from a total mortality point of view, broken out by cause. There may be some other positive mortality effects other than traffic deaths, but I’m willing to bet it will be the largest component of good mortality experience for 2020.
Hey, take the good news where you can find it!