I just realized that I'm forgetting also that in this particular period we had the most massive migration of people in Europe since WWII. This could also be a f

I just realized that I'm forgetting also that in this particular period we had the most massive migration of people in Europe since WWII. This could also be a facilitator in the path faeces-water-oral. If it was covid I assume that the problem would be detected before and would appear widespread by in all continents at the same time. Hitting much harder the countries with more number of Covid cases. But what we have instead is a (mostly) Atlantic European issue. (Spain, Denmark, Ireland, Scotland. Looks like a pattern here [1]). Europe had only two rare global events in this time interval that I am aware, the dust affecting the Western countries of Europe (if I'm not wrong), and the war. [1] (Scomber fish migration?... probably not, but also happened in this time and all hypotheses are valuable).