Primary care data
All countries reported activity of respiratory infections below threshold levels, where thresholds existed, based on syndromic surveillance data for influenza-like illness (ILI) and/or acute respiratory infection (ARI).
All 18 Member States and areas reporting on intensity reported low intensity for weeks 21–25/2018
Of the 26 Member States and areas reporting on geographic spread for weeks 21–25/2018, most reported no activity, a few (3–5 countries) sporadic and one (the United Kingdom (Scotland)) reported local activity.
Viruses detected in sentinel-source specimens (ILI and ARI)
For weeks 21–25/2018, 6 (1%) of 576 sentinel specimens tested positive for influenza viruses; five type A and one type B.
For the season overall, more influenza type B (63%) than type A (37%) viruses were detected, although between weeks 40/2017 and 44/2017 and since week 12/2018 the proportion of type A viruses detected has been higher than that of type B viruses. Of subtyped A viruses, 65% were A(H1N1)pdm09. While the majority of type B viruses was not ascribed to a lineage, 97% of those that were belonged to the B/Yamagata lineage.
Details of the distribution of viruses detected in non-sentinel-source specimens can be found in the Virus characteristics section.