[wosk]

True. We estimated seroprevalence for cantons ("states" of Switzerland, ranging from small to very small). As you says, there is some quite some difference (Fig. 5): Tessin (border with Italia) and French-speaking cantons (Geneva, Vaud) have a much higher seroprevalence than the rest of the country.

The same has been found by other groups on France.

[lbeltrame]

I think it's quite important, because it may drive local public policy depending on the results: especially if one considers the models of "shield immunity" (discussed at length in one Nature publication a few weeks ago) in reducing transmission (no government has taken interest in them, AFAICS).