Long-term scenarios for the number of new hospitalizations during the Belgian COVID-19 epidemic: RESTORE consortium Report

This report describes the combined impact of different social distancing scenarios, the 501Y.V1 variant and the ongoing vaccination campaign in Belgium and illustrates the importance of epidemic control in the period up to August 1, 2021. • Changing social distancing behaviour as a result of lifting measures too soon might, in spite of the ongoing vaccination campaign, still lead to a substantial fourth hospitalization wave. However , postponing behavioural changes that increase viral transmission allows the vaccination campaign to offset the transmission risk and associated disease burden. • Vaccination and seasonality (currently not modelled) are expected to have a positive impact on the incidence of new hospitalisations in the coming period. However, recent evidence from the UK and Denmark indicated that the 501Y.V1 variant is associated with a higher per-case probability of severe and lethal disease. The SIMID and UNamur models explicitly account for a VOC-related increase in transmission and per-case probability of hospitalization, while the UGent model implicitly captures the overall increase.