[russellw]

Sweden and Switzerland make an interesting case study as they have similar size populations but have adopted opposite strategies for dealing with Coronavirus; the former choosing a herd immunity approach and the latter using a model not dissimilar to ours.

Note: There is a big difference in population density - 219 km² for Switzerland and 22.2 km ² for Sweden and there is also a substantial difference in the amount of testing with Switzerland having tested 5593 / 100k while Sweden has only done 2910 / 100k. Both of those factors will obviously impact any comparison.

Having said that, they have not dissimilar case numbers per 100k of population with Sweden having 452 and Switzerland 437 but where they do vary substantially is the deaths per 100k of population with Switzerland almost half the rate of Sweden (27.1 v 53.6) despite the higher population density.

Hypothesis time.

I'd argue that if Sweden had the same level of tests and only identified cases at the same level as Switzerland (12 tests to each positive) then the extra 160k tests would yield another 13k cases and make the case rate per 100k about 50% higher than Sweden. Conversely, it would also make the mortality rates almost identical which not only suggests that those numbers are more realistic but leads to the reasonable conclusion that the 50% higher infection rate is the price paid for taking the herd immunity approach but that mortality rates might still be about the same anyway.

Of course, it's a comparison that is fraught with difficulties so it may offer no more than an indicator.