Fig. 4

Weekly model inputs for the study period (July to November 2021) for A estimated travel volumes into Canada for essential and non-essential travellers, B proportions of fully vaccinated travellers estimated for essential travellers given global vaccine coverage [5] and reported for non-essential travellers [23], and model output for C percent positivity and D number of imported COVID-19 cases into Canada as stratified into essential and non-essential travellers and combined (overall) for the baseline scenario (pre-departure testing of all non-essential travellers), counterfactual scenario 1 (no pre-departure testing of fully vaccinated non-essential travellers) and counterfactual scenario 2 (no pre-departure testing of any non-essential travellers). In C) and D), the essential traveller curve is identical for all three scenarios since the model for essential travellers was not repeated for the counterfactual scenarios