Syndromic surveillance data
Of the countries and areas in which thresholds for ILI activity are defined, countries in eastern (n=3; Azerbaijan, Kyrgyzstan, Russian Federation), northern (n=2; Estonia, Ireland), southern (n=1; Serbia) and western (n=5; Austria, Belgium, Hungary, Luxembourg, Switzerland) areas of the European Region reported activity above baseline levels.
Of the countries and areas in which thresholds for ARI activity are defined, countries in eastern (n=2; Kyrgyzstan, Russian Federation), northern (n=2; Estonia, Latvia) and western (n=1; Czechia) areas of the European Region reported activity above baseline levels
Assessment of the syndromic surveillance data of ILI or ARI rates might be driven by respiratory infections other than influenza virus, including SARS-CoV-2, leading to observed increases in the absence of influenza virus detections. The thresholds mentioned are based on the MEM method and based on historical ILI/ARI data.
Viruses detected in sentinel-source specimens (ILI and ARI)
For week 47/2021, 26 (2%) of 1 471 sentinel specimens tested positive for an influenza virus; 24 (92%) were type A and 2 (8%) were type B. Of 14 subtyped A viruses, 100% were A(H3). Of 22 countries or areas across the Region that each tested at least 10 sentinel specimens for week 47/2021, only 1 reported a rate of influenza virus detections above 10%: Kosovo (in accordance with UN Security Council Resolution 1244 (1999)) (43%).
For the season to date, 139 (1%) of 10 461 sentinel specimens tested positive for an influenza virus. More influenza type A (n=133, 96%) than type B (n=6, 4%) viruses have been detected. Of 99 subtyped A viruses, 98 (99%) were A(H3) and 1 (1%) was A(H1)pdm09. No influenza type B viruses were ascribed to a lineage.
Details of the distribution of viruses detected in non-sentinel-source specimens are presented in the Virus characteristics section.
External data sources
Influenzanet collects weekly data on symptoms in the general community from different participating countries across the EU/EEA. Please refer to the website for additional information for this week.