Mitigation strategies for responding to the COVID-19 pandemic after reopening from the global perspective

Abstract

The reopening following worldwide lockdown marked a new chapter in the COVID-19 pandemic, and multiple strategies were implemented globally to prevent the spread of COVID-19. However, the most important mitigation strategy for slowing the spread of the Omicron variant as well as the interaction effects of mitigation strategies remain unknown. To address this issue, we reconstructed the actual stage of infection and quantified the effects of vaccination, mask usage and the timing of reopening on infection reduction from the geographic perspective of regional differences. Vaccination was the primary driving factor behind the reduction in the transmission of the Omicron variant. The contribution of vaccination to the reduction in infection rate was 42.93 %, and when the rate of vaccination reached 80 %, the infection rate was reduced by approximately 0.02 %, which was equivalent to preventing approximately 1,418,589 infections across 127 countries. The threshold for the best effect of vaccine was 81.40 %. The mask usage alone had a limited impact on reducing infection rate; when the rate of mask usage was approximately 40 %, the infection rate was reduced by approximately 0.001 %. A prolonged delay reopening cannot reduce the infection rate, the best option is to increase the vaccination rate to >80 %. When the vaccination rate reached 80 % and the reopening time was 90 days, the reduced infection rate was approximately 0.03 %. This study provides a reference for reducing the infection risk and responding to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants in the future.