How old are the buildings in Italy? Do they have common air headers, are there air gaps where sound and air go from one apartment to another? Are windows open much of the time at this time of year?
Italian cities, like most of Europe, are compact and really piled on top of each other. While China is similar, a lot of their cities are brand new (not sure on the quality though). Are living conditions to blame?
While US cities have some areas like that, especially poorer areas, much of the areas are individual houses on tiny lots. Suburban dwellers have even more room.
I wonder much this might have to do with continuing spreads...
Ehm... no its not like that...
Firth of all old building are actually better then the new on concerning the room isolation since the wall are much ticker, they at least could have problem with windows since the woodframe that are not so tight sealing, but for the room-to-room that is not a problem!
Also, diffuson of the CoVid even if is spread across all the country is more focus on a single region and around Milan area: like 2/3 of the case most concentrated....
City are abit crumped all across Italy that is true and some more then other, but that is not a factor as it seams.
My personal idea is that is releted to a sum of factor, that include the type of city, the habits of the people and the general activity that took place in there.
For exaple MIlan is a very large city and the economical centrer of the country, so there are a lot of people moving for work in and out fo the city form all the region every day much more then any other city in Italy. That is a huge factor in the contagius spreading.
Also commercial activity in Milan are of course not factory, but office generaly medium small (due to the hight price of squared space footprint), so people are general tight in small office, and that favor the spread.
Fianally I've noitice that sicne the city has a good metro network and public trasport service, people are not used to walk that much, like to make 500m they used to take the but or the metro...
Of course a lot o peole in a closed eviroment like a metro or a bus is not the best for cointaining the spread...
If you look at the spread of the contagius area in different italian city you'll see that is not so wide, as it seams form the global number.
Sicily and the south of italy foor exaple ware city are more open but also thare aren0t soo many office sicne the main earning is turism and argiculture are not so affected, Sarinia and Sicily are basically un-effected with a reaally lower case count.