An agent-based model to assess the effect of the “social-bubbles’’ as lockdown exit strategy on COVID-19 transmission

Details

Supervisors

Speybroeck, Niko

Faculty

Faculté de santé publique

Degree label

Master [120] en sciences de la santé publique, à finalité spécialisée

Abstract

With the success of the lockdown measures to decrease the amount of COVID-19 cases, countries had to lift measures to regain social interactions. Part of the Belgian strategy to mitigate the impact of COVID-19, was through the concept and implementation of “social bubbles”. The bubbles have the goal to allow contacts but in a clustered way aiming to limit the spread of the virus. In Belgium, the size of the bubbles changed with the evolution of the pandemic. The strategy of working with bubbles resulted in criticism and reluctance from the population, not always understanding the usefulness of the measure. The goal of this study is to model the impact of social bubbles on the spread of COVID-19. I used an agent-based SEIR (Susceptible-Exposed-Infected-Recovered) model with the purpose to better understand the usefulness of social bubbles during an exit lockdown strategy. Six different scenarios were performed with SEIR graphs indicating the course of the pandemic conditional on a selected strategy. The first scenario was a baseline scenario where people meet each other in a non-clustered way. The next three scenarios mimicked population with restricted contact through the implementation of social bubbles of different sizes. In the last two scenarios, we model a social bubble strategy that is poorly respected where the households change their friends (bubble) every week. The model helps us to visualize how the epidemic will occur when an intervention such as social bubbles is set up. It assesses the impact of changes in the parameters like the bubble size, the secondary attack rate, the proportion of asymptomatic patients, the duration, the number of persons initially infected. It provides a useful tool, which can assist politicians to finetune further interventions against pandemics of infectious diseases.