A New Epidemic Model for the COVID-19 Pandemic: The θ-SI(R)D Model

Abstract

Since the beginning of the COVID-19 pandemic, a large number of epidemiological models have been developed. The principal objective of the present study is to provide a new six-compartment model for the COVID-19 pandemic, which takes into account both the possibility of re-infection and the differentiation between asymptomatic and symptomatic infected subjects. The model, denoted as θ-SI(R)D, is a six-compartment model, described by as many ordinary differential equations. The six compartments are denoted as Susceptible (S), Symptomatic Infected (Is), Asymptomatic Infected (Ia), Recovered from Asymptomatic fraction (Ra), Recovered from Symptomatic fraction (Rs), and Deceased (D). Such a model has no analytical solutions, so we performed both a simulation and a model validation (R2=0.829). Based on the results of our simulations (and, on the other hand, on the results of most of the models in the scientific literature), it is possible to draw the reasonable conclusion that the epidemic tends, even without vaccination, to a steady state.

An Interactive Dashboard for Statistical Analysis of Intensive Care Unit COVID-19 Data

“…The evolution of this pandemic and its consequences were reflected in the mortality and morbidity of populations, leading to the development of several scientific studies and research projects all over the world [1][2][3][4][5][6][7][8][9][10][11]. For instance, the study carried out by Florensa et al [1] was carried out in Lleida, Spain, and compared the Alpha variant, first detected in the United Kingdom, and the Delta variant, first detected in India.…”