Primary care data

Influenza activity

For week 45/2017, low intensity of influenza activity was reported by all of the 42 countries reporting on this indicator.

No geographic spread was reported by 21 of the 43 countries reporting on this indicator, while sporadic cases or local geographic spread was reported by 22 countries.

Based on syndromic surveillance data for influenza-like illness (ILI) or acute respiratory infection (ARI), all countries are below their respective epidemic thresholds for influenza activity.

Viruses detected in sentinel-source specimens (ILI and ARI)

For week 45/2017, 33 (4.5%) of 739 sentinel specimens tested positive for influenza viruses: 6 A(H1N1)pdm09, 4 A(H3N2), 3 unsubtyped A viruses, 3 B/Yamagata lineage and 17 B viruses not ascribed to a lineage.

Of 15 countries across the region that each tested at least 10 sentinel specimens, 2 countries in western Europe reported proportions of influenza virus detections above 10% (France with 15% and Scotland with 18%).

Since week 40/2017, 50% of detected viruses (n=100) were type A and 50% type B. Of subtyped A viruses (n=33), 60% were A(H3N2). Of 14 influenza B viruses ascribed to a lineage, 13 were B/Yamagata.

Details of the distribution of viruses detected in non-sentinel-source specimens can be found here.