1. Global patterns in monthly activity of influenza virus, respiratory syncytial virus, parainfluenza virus, and metapneumovirus: a systematic analysis;Li Y;Lancet Glob Heal,2019
2. Influenza seasonal. (2021). Accessed. June 2, 2021: https://www.who.int/en/news-room/fact-sheets/detail/influenza-(seasonal).
3. Factsheet about seasonal influenza. (2021). Accessed. June 10, 2021: https://www.ecdc.europa.eu/en/seasonal-influenza/facts/factsheet.
4. Coronavirus disease (COVID-19) pandemic. (2020). Accessed. June 2, 2021: https://www.euro.who.int/en/health-topics/health-emergencies/coronavirus-covid-19/novel-coronavirus-2019-ncov.
5. WHO Influenza update report. (2021). Accessed. June 8, 2021: https://www.who.int/teams/global-influenza-programme/surveillance-and-monitoring/influenza-updates/influenza-updates-....