1. Influenza (seasonal): World Health Organization; 2018 [Fact Sheet No.211. Available from: https://www.who.int/news-room/fact-sheets/detail/influenza-(seasonal).
2. Canadian Immunization Guide Chapter on Influenza and Statement on Seasonal Influenza Vaccine for 2020-2021. In: Canada PHAo, ed.; 2020.
3. Intraseason waning of influenza vaccine protection: Evidence from the US influenza vaccine effectiveness network, 2011–12 through 2014–15;Ferdinands;Clin Infect Dis,2017
4. Do antibody responses to the influenza vaccine persist year-round in the elderly? A systematic review and meta-analysis;Young;Vaccine,2017
5. Intra-season waning of influenza vaccine effectiveness;Ray;Clin Infect Dis,2018