Modeling Covid-19 Considering Asymptomatic Cases and Avoided Contacts

In this chapter we presented a mathematical model that describes the transmission of the novel coronavirus, SARS-CoV-2. The model considers both symptomatic and asymptomatic cases. Moreover we introduce a parameter for the fraction of avoided contacts that represents the precautionary measures to avoid contact between individuals, such as social distancing, lockdown and/or wearing masks. In this study we focused our attention on the importance of the parameter values on the basic reproduction number, R 0, with special regard on the fraction of avoided contacts, the fraction of avoided contacts once infected (or vice versa of undergoing symptomatic) and finally on the recovery rate of asymptomatic individuals. From the numerical simulations an important result regards the fraction of avoided contacts, increasing this parameter helps not only to delay the peak of the maximum number of infected individuals but also to decrease it. The measures to decrease the maximum number of infected individuals and to delay the peak are important in those cases where the hospital system does not have enough seats in the intensive care unit. Here we focus our attention on data from Italy. Considering the limitations that a simple mathematical model can have, consequently the obtained results must be interpreted in this perspective.