When will the Covid-19 epidemic fade out?

Ilaria Renna

Each individual of a population is represented by a node of a small world network [4] . The host population is partitioned into categories containing susceptible S, infectious I, and recovered individuals R (SIRS model). Each node is characterized by a counter " . A susceptible individual S( " = 0) can come into the infected state through contagion by infected ones. An infected individual I( " = 1) passes to the refractory state R after an infection time ( , and a refractory individual returns to susceptible state after immunity duration ) [5] . The cycle is completed after these ( + ) time steps, when it returns to the susceptible state. The contagion of susceptible elements occurs stochastically at a local level. If a susceptible element i has " neighbours, of which ",-are infected, then it will become infected with probability / 0 = ",-" . Detail are given in [3] . As it can be seen from this figure, the trend of the infected is exponential ∝ 56 , with = 0.13days >? . Most likely, this value will decrease, in the coming days, given the very restrictive conditions on the movements of the population enforced by the Italian Government.