Careful What You Wish For — Open Questions On Covid-19
Paul Krugman published an exquisitely sophisticated analysis of the Covid-19 situation, as befits an economics Nobel laureate. The piece, “Why Can’t Trump’s America Be Like Italy?”, appeared a few days ago in the New York Times.
Summarized for mere mortals like the rest of us, Krugman’s argument runs as follows — pay close attention, because the logic is a bit subtle:
Trump bad. Italy: no Trump. US: Trump. Italy: no coronavirus. US: apocalypse.
Irony aside, the article highlights some important open questions.
First question: how should we compare today the experience of different countries in the pandemic?
If you live in the US, should you really wish that the US were like Italy? Italy has suffered 581 Covid-19 deaths per million of population, the US 465 (data as July 29). So if the US were like Italy, it would have suffered about an additional 40,000 casualties to date, raising its current death toll by 25%. By this metric, Italy does not appear to be a desirable alternative.
Krugman points out correctly that after a rough start, new cases and new deaths in Italy are now much lower than in the US. By this metric, Italy looks better. But what if US contagion comes back under control over the next month, leaving the US with still a lower overall mortality than Italy? My view is that it’s still too early to make definitive comparisons.
Second question: which strategies have proved more effective to limit the damage from Covid-19?
Krugman argues that Italy has brought the virus under control because “It instituted a very severe lockdown, and kept to it.”
Sounds plausible. Except that Sweden is also faring much better than the US and also seems to have brought contagion under control. Sweden never instituted a full lockdown (and for this it has been repeatedly vilified by the New York Times amongst others).
The chart below shows new cases per million of population, as a 7-day average. Spain, Italy, France and Germany peaked early and then experienced a rapid reduction — Spain and Italy fared far worse than others. Sweden’s cases remained initially higher and experienced a second wave in June — but they have fallen sharply through July and have now converged to the others. Meanwhile Spain’s progress appears to have reversed and its new cases (per million of population) are now higher than Sweden. New cases in the US have spiked, though they appear to have stabilized since mid-July.
Sweden’s deaths per million of population are still lower than Italy, albeit by a small margin.
As of today, Italy and Sweden seem to have been equally successful in bringing contagion under control. Italy did it with a full lockdown, shutting down all schools and businesses and handing people a heavy fine if they took their dog for a walk and strayed more than 200 meters away from their home. Sweden never closed it schools and allowed businesses to keep operating, though it recommended social distancing. It would be useful to understand better which measures helped and which did not.
Meanwhile, the charts above suggest that asking “Why can’t Trump’s America be like Sweden” would be an equally and even more sensible question.
Third question: why have some areas suffered so much more than others even within the same country?
Krugman observes that the US northeast corridor suffered heavily at the beginning, but then learnt its lesson and took the virus seriously, like Italy, achieving the same success. However, though it is far smaller than the US, Italy is not a homogenous entity either. Commentators repeatedly warned that the south of Italy was not taking the virus seriously, was not enforcing social distancing, and would suffer a serious outbreak — especially after thousands of people fled the heavily affected northern Lombardy region in crowded trains and buses when the decision to lock down the region was leaked to the press last March. Yet the south never suffered a major outbreak. Now take a look at the next chart, which shows total Covid-19 deaths per million of population:
New York State and Lombardy have suffered a very similar mortality rate; the same holds for the US northeast corridor, or greater New York metropolitan area, including New York State, New Jersey and Connecticut. Excluding this corridor, the rest of the US has a mortality rate 5 times lower than New York State. Lombardy has a mortality rate 4.6 times higher than the rest of Italy. Mortality in New York City has been even higher, 8 times more than in the rest of the US.
When we start preparing for the next pandemic, where would you rather be? Most definitely not New York City. Somewhere in the US outside the northeast corridor still seems most attractive, followed by somewhere in Italy outside Lombardy. Maybe Wyoming, with the US’s third lowest Covid mortality rate. Or perhaps the Tuscan countryside.
These data don’t suggest the question “Why can’t Trump’s America be like Italy?” They scream the question “Why can’t Cuomo’s New York State be like the rest of the US?” Which in the circumstances might also be a more natural question for a New York City professor writing for a New York City paper.
Using these regional differences to play the blame game can be fun of course, but it would be more useful to try to understand what drives them.
Anders Tegnell, Sweden’s Chief epidemiologist, notes in this podcast that Sweden experienced similar regional variations: the Stockholm area was hit hard, the south of the country was not. Tegnell admits that we don’t really know why. He surmises that Stockholm might have experienced a large number of simultaneous new cases as people came back from their spring break in southern Europe — but he admits it’s just a supposition. By the way, the podcast is well worth listening to; Tegnell is a great example of an expert who sounds pragmatic, transparent and very honest about what we do and do not understand about this virus yet.
In the US, California is one of the new hot spots, together with Florida and Texas. Florida and Texas have been accused of reopening their economies too quickly; California was the first US state to implement a full lockdown and has reopened only partially and cautiously. Yet look at the chart:
The trend in new cases is almost identical across the three states (don’t compare the absolute numbers, this chart shows the total number of new cases, and California has almost 40 million people to Texas’ 30 and Florida’s 20, so relative to population size California looks uniformly better, but here I’m interested in the trends). So here we have three states with different policies and identical contagion dynamics — what are the lessons?
Fourth question: are masks really useful?
The idea that face masks should prevent or at least hinder the transmission of the virus makes intuitive sense to me, and so I always wear one. But Sweden has not required people to wear masks. Asked why, Professor Tegnell answers that they have not seen any convincing scientific evidence that masks help. He argues that social distancing does make a difference, but there is no evidence that masks do. Before we dismiss his opinion, let’s keep in mind that both the World Health Organization and US top epidemiologist Doctor Fauci have gone back and forth on masks recommendations. Also, experts have often told us that a mask will stop you from spreading the virus, but will not prevent you from breathing the virus in; this has always made less sense to me, as a mask is not a one-way barrier. The fact that we are not even sure that masks help is a sobering reminder that the naïveté of believing in one single measure as the silver bullet can be dangerous.
Last question: why can’t we have an honest debate on these questions?
After months of research and data, some very basic and important questions remain wide open. We know more than we did back in March, and we are making progress: even in the US, Covid-19 deaths have risen far less than new cases. But we are still learning how to control contagion and limit the death toll. Covid-19 might be here to stay — even a vaccine might not be enough to eradicate it completely. If so, we have to learn how to live with it. Our best chance is through an honest, fact-based debate, by admitting we don’t have all the answers yet, by seeking and offering better information while exercising caution and following the health guidelines. If we keep basing our arguments on fact-free partisanship, à la Krugman, we’ll never get the answers. And we’ll be stuck with a grossly distorted view of the risks driven by partisanship and misinformation, as a recent Gallup-Franklin Templeton study shows with some striking and depressing numbers.