Control of COVID-19 Outbreak for Preventing Collapse of Healthcare Capacity based on Social Distancing, Confinement and Testing-Quarantining

Abstract

This work is a contribution to the call to The IFAC-CSS Corona Control Community Project in February 2020. Scientific evidence to the effectiveness of the three main non-pharmacological tools to mitigate a pandemic is given. A control system to control the Covid-19 outbreak caused by the Sars-CoV2 virus, called Coronavirus, is proposed, for preventing collapse of the health systems and saturation of Intensive Therapy Units (ITUs) capacity. The proposed system is based on the three existing non-pharmacological tools for the mitigation of epidemics and pandemics: social distancing, confinement and testing with isolation of a population in which there is community circulation of the virus. Both in the analysis and in the design of the control system, the mathematical model SEIRD (Susceptible - Exposed - Infected - Recovered - Deceased) is used, which describes the dynamics of a pandemic, adjusted in this work to the behavior in space and time of the Sars-CoV2. In this work the incidence and impact of testing with isolation (or testing-quarantining) is incorporated in the model. The proposed control system uses, as a feedback signal, the demanded quantity of critical beds and ITUs, which is compared with the available beds capacity to generate the error signal as input to a PID controller. As control actions, five Phases of Social Distancing and Confinement (SD&C) are proposed, which must be applied by the public authority. The control system thus generates a SD&C decision sequence or policy, which can be applied once a week or every fortnight. Simulation results showing the practical feasibility and good performance of the proposed control system are given, preventing collapse of Healthcare Capacity based on Social Distancing, Confinement and Testing-quarantining as control actions.