Seasonal influenza - Annual Epidemiological Report for 2020-2021

Surveillance report
Publication series: Annual Epidemiological Report
Time period covered: Seasonal data in this report, covering the period from week 40/2020 to 20/2021, were extracted from the database during week 21/2021 for the reporting week 20/2021.

European Centre for Disease Prevention and Control. Seasonal influenza. In: ECDC. Annual epidemiological report 2020. Stockholm: ECDC; 2021.

For the EU/EEA, influenza activity remained at or below inter-seasonal levels throughout the 2020−21 season, probably due to the impact of the various public health and social measures implemented to reduce transmission of SARS-CoV-2.

Executive summary

  • Only 10 sentinel and 158 non-sentinel specimens tested positive for influenza during the 2020−21 season. Compared with previous seasons a slightly lower number of samples were tested in sentinel surveillance and a similar number in non-sentinel surveillance. However, there was a remarkable decrease in the number of influenza infections detected, with numbers detected on a weekly basis being similar to those reported during the inter-seasonal periods for both sentinel and non-sentinel surveillance systems.
  • There were no hospitalised cases of influenza reported by EU/EEA countries in the 2020-21 season and neither were there any fatalities from influenza reported this season.
  • Very few viruses were sent for characterisation this season, which has hampered the decision on vaccine composition for the coming season.