A simplified model for the analysis of COVID-19 evolution during the lockdown period in Italy

Simeone, R.

A simplified model applied to COVID-19 cases detected and officially published by the italian government, seems to fit quite well the time evolution of the disease in Italy during the period feb-24th - may-19th 2020. The hypothesis behind the model is based on the fact that in the lockdown period the infection cannot be transmitted due to social isolation and, more generally, due to the strong protection measures in place during the observation period. In this case a compartment model is used and the interactions between the different compartments are simplified. The sample of cases detected is intended as a set of individuals susceptible to infection which, after being exposed and undergoing the infection, were isolated ('treated') in such a way they can no longer spread the infection. The values obtained are to be considered indicative as they depend not only on the quality of the data collected, but also on the qualitative approximation of the curves modeled to the data and on the number of available data. The same model has been applied both to the data relating to Italy and to some regions of Italy (Lombardia, Piemonte, Lazio, Campania, Calabria, Sicilia, Sardegna), generally finding a good response and indicatively interesting values.