COVID-19: Vaccination Our publications in English about vaccination and immunization against COVID-19 2 February 2023 - Administration of COVID-19 booster doses: Recommendations for winter and spring 2023 18 February 2021 - Preliminary Data on Vaccine Effectiveness and Supplementary Opinion on the Strategy for Vaccination Against COVID-19 in Quebec in a Context of Shortage 20 January 2021 - Requested supplement to the notice Strategy for Vaccination Against COVID-19: Postponement of the Second Dose in a Context of Shortage 31 December 2020 - Strategy for Vaccination Against COVID-19: Postponement of the Second Dose in a Context of Shortage