Discussing school closures and lockdowns, many people take Sweden as an example. “We should have done like them; they didn’t close and ended up relatively unscathed.”
This argument is built under the assumption that if we had done like Sweden, we would have ended up like Sweden. Is this a sensible assumption?
Only if early on in the pandemic, our country was doing as well as Sweden. However, in March 2020, field hospitals were built in Bergamo and New York but not Stockholm. Some Italian and American hospitals started being overwhelmed to a degree that Swedish ones didn’t.
This suggests that, if Italy and the US had followed Sweden’s strategy, they would have fared much worse.
Different countries might have different outcomes with similar policies
Imagine two fictional countries, A and B. On the 1st of February 2020, Country A had 10 infected people per million population, whereas Country B had 50 infected people per million population. Both countries follow the same public health policies.
Do we expect countries A and B to have the same number of cases on the 1st of April 2020?
Obviously not. Country B, which had more virus in the country to begin with, will have more cases, more deaths, and their healthcare system will be more overwhelmed – even if the two countries’ policies are identical.
Let’s make a second example. Country A and Country B both begin with the same number of cases on the 1st of February 2020, and both have the same policies, but country B is denser and their people are more social and that increases the risk of transmission by 20%. Obviously, we expect cases to grow faster in Country B.
Now, let’s say that Country B decides to lock down, and let’s imagine that locking down reduces transmission by 20%. In that case, the increased transmission inherent in Country B’s geo-social characteristics and the decreased transmission thanks to the lockdowns cancel each other, and Countries A and B will have the same number of cases. But that doesn’t mean that locking down was useless! In fact, if Country B hadn’t locked down, they would have fared much worse.
These two examples show why it’s pointless to use Sweden as a comparison.
The importance of the trajectory
How a country fared early in the pandemic tells us a lot about how much precautions it should use later on.
If a country started 2020 with relatively high cases and deaths, it’s probably an indication that the country has some intrinsic factor that makes it more vulnerable to covid than its peers:
- Maybe its population is relatively older or vulnerable
- Maybe its cities are more dense, air pollution is worse, etc.
- Maybe its population has working and social patterns that make them spend more time indoors in more crowded environments
- Maybe their healthcare system is less able to accommodate a surge in patients
- And so on.
That country should take higher precautions than its peers to get the same outcomes as them.
Anyone suggesting that a country can achieve the same outcome as a country with different characteristics by adopting the same policies is dangerously delusional.