Covid-19 Belgium: Extended SEIR-QD model with nursing homes and long-term scenarios-based forecasts

TL;DR

This paper develops an extended age-structured SEIR-QD model for COVID-19 in Belgium, incorporating nursing homes and long-term scenario forecasts to evaluate intervention impacts and epidemic evolution.

Contribution

It introduces a novel compartmental model that separately accounts for nursing homes and integrates diverse data sources for accurate epidemic prediction.

Findings

Model captures specific dynamics within nursing homes.

Provides long-term projections under various social contact scenarios.

Estimates key COVID-19 characteristics in Belgium as of November 2020.

Abstract

Following the spread of the COVID-19 pandemic and pending the establishment of vaccination campaigns, several non pharmaceutical interventions such as partial and full lockdown, quarantine and measures of physical distancing have been imposed in order to reduce the spread of the disease and to lift the pressure on healthcare system. Mathematical models are important tools for estimating the impact of these interventions, for monitoring the current evolution of the epidemic at a national level and for estimating the potential long-term consequences of relaxation of measures. In this paper, we model the evolution of the COVID-19 epidemic in Belgium with a deterministic age-structured extended compartmental model. Our model takes special consideration for nursing homes which are modelled as separate entities from the general population in order to capture the specific delay and dynamics within these entities. The model integrates social contact data and is fitted on hospitalisations data (admission and discharge), on the daily number of COVID-19 deaths (with a distinction between general population and nursing home related deaths) and results from serological studies, with a sensitivity analysis based on a Bayesian approach. We present the situation as in November 2020 with the estimation of some characteristics of the COVID-19 deduced from the model. We also present several mid-term and long-term projections based on scenarios of reinforcement or relaxation of social contacts for different general sectors, with a lot of uncertainties remaining.