Weekly influenza update, week 45, November 2017
ECDC and WHO/Europe publish weekly influenza surveillance data in the report Flu News Europe.
- Influenza activity across Europe remained at a low level.
- Overall, 4.5% of individuals sampled, on presenting with ILI or ARI to sentinel primary healthcare sites, tested positive for influenza viruses, which is a slight increase compared to the previous week (1%).
- Data from 19 countries or regions reporting to the EuroMOMO project indicated that all-cause mortality was at low levels, as expected for this time of the year.
2017/18 season overview
- Since week 40/2017, few influenza viruses have been detected in sentinel and non-sentinel specimens.
- For detections from both sentinel and non-sentinel surveillance systems, most viruses subtyped or assigned to a lineage this season were identified as A(H3N2) and B/Yamagata viruses, respectively.
- While low in number (n=21), over 80% of the A(H3N2) viruses genetically characterized belong to clade 3C.2a, the vaccine virus clade, as described in the WHO recommendations for vaccine composition for the northern hemisphere 2017–18.
Read more about influenza surveillance
Seasonal influenza is a preventable infectious disease with mostly respiratory symptoms. It is caused by influenza virus and is easily transmitted, predominantly via the droplet and contact routes and by indirect spread from respiratory secretions on hands etc.Read more
Surveillance reports and disease data on seasonal influenza
Surveillance reports and data: Disease data from ECDC Surveillance Atlas, Annual Epidemiological Reports, Surveillance reports.Read more