Between Geography and Demography: Key Interdependencies and Exit Mechanisms for Covid-19

Antonio Scala; Andrea Flori; Alessandro Spelta; Emanuele Brugnoli; Matteo Cinelli; Walter Quattrociocchi; Fabio Pammolli

Assuming that the right approach is the one with regional delays, we consider two possible exit strategies: in the first, that we call the Asynchronous scenario, each region i lifts the lockdown at the time t Unlock i when the peak of O Delay i decreases by 30%; in the second, that we call the Synchronous scenario, each region i lifts the lockdown at the same time t Unlock , i.e., when the global peak of O Delay decreases by 30%. Notice that, since once started epidemics become essentially uncorrelated processes for each region, it could be safe to let each region have its own unlock time respect to having a global unlock. In Fig. 4 we compare the effect of a region-to-region release of the lockdown respect to releasing the lockdown at the same time in all the regions for the case of Lazio and Lombardy: in the latter case, there is a risk of having regions that have started earlier the contagion to wait a too much long time, and to have regions that have started later to have a too much strong rebound. Since not only epidemics, but also the ruin of an economy is a non-linear process, the Sync scenario can turn out to be even more disruptive than the epidemic itself (see also Fig. 3 ). Notice that analogous arguments hold -mutatis mutandis -also for the world/countries scenario.