OBJECTIVES : Because of the COVID-19 pandemic, immunization against influenza for the 2020/21 season was paramount and many governments strengthened their influenza vaccination policies to protect their populations and spare their healthcare systems. The objective of this study was to evaluate the impact of COVID-19 on influenza vaccines sales.

METHODS : We focused on influenza vaccine sales or prescription/reimbursement for the influenza seasons 2015/16 to 2020/21 in France, UK and US. All influenza vaccine presentations were considered based on national recommendations for immunization. Data was collected for each season from September/October to January/February as we assumed vaccines could be administered during this period. Data for France and UK was extracted from the Assurance Maladie and the Vantage IQ databases that provide reimbursement and prescription data respectively. Finally, the CDC website provided the number of doses distributed in the US. We used non-parametric Wilcoxon signed-rank tests to investigate significant vaccine sales variations for the 2020/21 season compared to previous seasons

RESULTS : In France, 10.8 million doses were reimbursed in 2020/21, representing an overall increase of +33.6% compared to previous seasons (p=0.0313). Significant increases were observed for October 2020 (+106.5%) and January 2021 (+102.6%) (p=0.0313). Similarly, 12.7 million doses were prescribed in the UK in 2020/21 i.e +7.7% versus previous seasons (p=0.0313). Likewise, increases were evident during September (+27.9%) and December 2020 (+14.5%) (p=0.0313). In the US, 193.8 million doses were distributed in 2020/21, marking a +22.5% augmentation compared to previous seasons (p=0.0313), with significant increases noted for October (+68.6%), November (+49.0%) and December 2020 (+52.9%) (p=0.0313).

CONCLUSIONS : We observed a significant increase in influenza vaccine sales for the season 2020/21 compared to previous seasons, probably in order to limit the impact of a Sars-CoV-2/influenza co-circulation. Vaccine sales/reimbursements for the 2021/22 season should also be investigated as the pandemic is still ongoing.