Infection dynamics of COVID-19 virus under lockdown and reopening

TL;DR

This paper models COVID-19 infection dynamics under lockdown and reopening policies, emphasizing the importance of swift, decisive actions and international coordination to prevent healthcare system overload.

Contribution

It introduces a stochastic model for COVID-19 spread and compares policy effectiveness, highlighting the need for rapid response and coordinated reopening strategies.

Findings

Harsh lockdowns or swift reactions prevent hospital overload

Swift reactions are universally beneficial for controlling spread

Coordination between countries enhances reopening safety

Abstract

Motivated by COVID-19, we develop and analyze a simple stochastic model for a disease spread in human population. We track how the number of infected and critically ill people develops over time in order to estimate the demand that is imposed on the hospital system. To keep this demand under control, we consider a class of simple policies for slowing down and reopening the society and we compare their efficiency in mitigating the spread of the virus from several different points of view. We find that in order to avoid overwhelming of the hospital system, a policy must impose a harsh lockdown or it must react swiftly (or both). While reacting swiftly is universally beneficial, being harsh pays off only when the country is patient about reopening and when the neighboring countries coordinate their mitigation efforts. Our work highlights the importance of acting decisively when closing down and the importance of patience and coordination between neighboring countries when reopening.