Estimate of the development of the epidemic reproduction number Rt from Coronavirus SARS-CoV-2 case data and implications for political measures based on prognostics

Sahamoddin Khailaie; Tanmay Mitra; Arnab Bandyopadhyay; Marta Schips; Pietro Mascheroni; Patrizio Vanella; Berit Lange; Sebastian Binder; Michael Meyer-Hermann

The implemented SECIR-model is an extended version of state-of-the-art deterministic ordinary-differential-equation models. It distinguishes healthy individuals without immune memory of CoV (S), infected individuals without symptoms but not yet infectious (E), infected individuals without symptoms who are infectious (C), and identified symptomatic patients (I). Further, compartments for hospitalization (H) and intensive care units (U) were introduced to monitor the load on the healthcare system. Patients recover from different states of the disease (R) or die (D). The quantities are defined and the model is summarized in Figure 1 with parameters in Table 1 The model further distinguishes recovered cases according to whether they were recorded or not. If a person directly recovers from the carrier state (RC with rate R9), it is not counted for the cumulative recorded number of cases, which is calculated as I+H+U+D+R-RC.