Weekly influenza overview

Weeks 31-35/2023 (31 July-03 September 2023)


·       Influenza activity remained at interseasonal levels.

·       Bulgaria, Ireland, Kazakhstan, Malta and Slovakia reported low influenza intensity and Scotland reported regional influenza activity.

·       Display of data will be updated on a monthly basis during the interseason period (weeks 21-39).


Qualitative indicators


Information on countries and areas reporting on intensity of activity and geographic spread for this week can be seen in the Figures below.


Please note:


Assessment of the intensity of activity indicator includes consideration of ILI or ARI rates. These 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.


Assessment of intensity and geographic spread indicators includes consideration of sentinel and non-sentinel influenza virus detection data. Non-sentinel influenza virus detections, often higher, might translate into reporting of elevated geographic spread even in the absence of sentinel detections and/or low intensity of activity measured by ILI and ARI incidence.  


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© European Centre for Disease Prevention and Control 2023
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