Virus Characteristics

Details of the distribution of viruses detected in sentinel-source specimens can be found in the Primary care data section.

Non-sentinel virological data

Please refer to the Figure and Table below for additional information on non-sentinel specimens tested for influenza viruses for this week.


Genetic characterization


Please refer to the Table below for additional information on viruses that have been characterised genetically


Currently, WHO Europe and ECDC’s February virus characterization report is available and describes available data from circulating viruses for the early weeks of the 2022-2023 influenza season.


Previously published influenza virus characterization reports are available on the ECDC website and the WHO web site.



Antiviral susceptibility of seasonal influenza viruses

Between weeks 36 and 39/2023, 8 virus was assessed for susceptibility to neuraminidase inhibitors and 7 to baloxavir marboxil. Phenotypically and/or genotypically, no markers associated with reduced susceptibility were identified.