One of my biggest problems in dealing with Covid-19 has been sorting out the information that we are deluged with on a daily basis. I thought this explanation from the Sbarro Health Research Organization was a help.
Not long after the Coronavirus disease (Covid-19) outbreak in China, Italy was hard-hit by the infection and rapidly became one of the countries with the highest mortality rate. The disease was first detected on February 20 in Lombardy, a region in the Northern area, and rapidly spread throughout the country. The Southern regions and the Islands, however, registered much lower infection rates even though a massive migration from the affected regions to the South was recorded before the national lockdown.
What spared the South of Italy from such a heavy disease burden? Various reasons have been proposed including that milder climate conditions in the South could have helped to prevent viral spreading, but none so far convincingly explained the different incidence rates throughout the country.