Evaluation of Contact-Tracing Policies Against the Spread of SARS-CoV-2 in Austria – An Agent-Based Simulation

Abstract

AbstractBackgroundMany countries have successfully managed to stop the exponential spread of SARS-CoV-2. Still, the danger of a second wave of infections is omnipresent and it is clear that every containment policy must be carefully evaluated and possibly replaced by a different, less restrictive policy, before it can be lifted. Contact tracing and consequential breaking of infection-chains is a promising strategy to help contain the disease, although its precise impact on the epidemic is unknown.ObjectiveIn this work we aim to quantify the impact of tracing on the containment of the disease.DesignWe developed an agent-based simulation model that simulates the spread of the disease and allows for exploratory analysis of containment policies. We apply this model to quantify the impact of contact tracing in different characteristics in Austria and to derive general conclusions on contract tracing.ResultsThis modelling study displays the dynamics of the interplay between strictness of the tracing policies, isolated persons, and active COVID-19 infections. It shows that a strict tracing policy does not necessarily imply that the total number of quarantined persons is high as well, because the disease is better contained.LimitationsThe results are limited by the validity of the modeling assumptions, model parameter estimates, and the quality of the parametrization data.ConclusionsThe study shows that tracing is indeed an efficient measure to keep COVID-19 case numbers low but comes at the price of too many precautious quarantined people if the disease is not well contained. Therefore, contact tracing must be executed strictly and compliance within the population must be held up to prevent new disease outbreaks.