Two Approaches for Identifying Epidemiological Parameters Illustrated with COVID-19 Data for Bulgaria

This work focuses on special numerical techniques for identifying time-dependent epidemics parameters such as infection and recovery rates, and the corresponding basic and effective reproduction numbers. The first method is based on solving the inverse problem for coefficients’ identification in an Adaptive Susceptible-Infected-Removed (A-SIR) epidemic model with time-dependent infection and recovery rates. The second approach is based on direct integration of the SIR system of ordinary differential equations and the least square method. This approach is limited to estimation of the basic and effective reproduction numbers. The developed methods are used for identifying the parameters with real data for COVID-19 for Bulgaria. The results demonstrate how well the methods simulate the dynamics of the infectious disease.