COVID-19: What have we learned?
In mid-March, when I naively attempted to model the total number of COVID-19 cases in the subsequent week in the US, the US reported 3,000 confirmed cases and was 8th in the list of countries based on cases reported. As of today, the US is close to 6M confirmed cases, topping the world in both the number of cases and deaths.
To put the US numbers in perspective, it helps to compare it with peers in Europe that have seen a significant increase in COVID cases - Spain, UK, France, Italy and Germany. All of them with the exception of the UK, were ranked above the US when we looked at the numbers in mid-March. Their combined population, of 324M, also compares well with the population here in the US of 328M.
We observe that the number of cases in the US is nearly 4 times the case count in the 5 countries of Europe, and deaths are about 1.25x that of the Europe. There are 2 additional dimensions worth highlighting. The median age in Europe is higher than in the US suggesting a possibly higher at-risk population. The population density for the European countries is higher than that in the US suggesting a higher likelihood to get infected. Both of these point towards higher cases and mortality for Europe compared to the US. How is it that the 5 countries in Europe as a group still fare better?
It helps here to break down the metrics by country and compare it to the US. I have also included California which has a population and area (sq. miles) comparable to the chosen nations in Europe.
We observe that each of the countries we picked in Europe have a higher median age than the US, and a much higher population density than the US. All else being equal, they should have worse case and infection numbers than the US. Since the number of confirmed cases is also a function of testing, we will focus instead on deaths per 1M people in the population. Germany and France are 2 of the 5 that have a lower death/1M number compared to the US, with Germany being significantly lower at one-fourth the number for France. When compared to California, only Germany stands out as having signifcantly lower deaths per million people.
Now, the fatalities due to COVID depend on a number of factors that we haven’t accounted for - the prevalance of pre-existing conditions, median age and health condition for those infected, the quality of healthcare - among others. These factors can explain some of the sources of variation in the results. Despite the crude nature of the analysis, the exceptions stand out. Germany’s metrics are a head and shoulder above the rest, and the difference is wide enough that it cannot be explained away by chance alone. As an example, if the US had the same deaths per 1M as Germany, the number of deaths in the US would have been 36,765 i.e. 146,090 fewer deaths! To be fair, applying the UK metric here would result in a death toll in the US of 204,779 - higher by 9,415. All else being equal, 9415 might be within a margin of error, but 146,090 is too large a difference to be attributed to chance alone.
While a clear picture on the pandemic and how it has been handled may only emerge once we are past the fog of war that is the ongoing pandemic, it is never too late for the nations that are, well, just average or worse, to borrow a page from those that have done exceptionally. The first step, of course, is to acknowledge that one can do better.