Week 04/2020 (20-26 January 2020)

  • Influenza activity continued to increase, with 1 Member State reporting very high, 3 high and 12 medium intensity. Widespread influenza activity was reported by the majority of Member States and areas across the Region.
  • Of the individuals sampled who presented with ILI or ARI to sentinel primary healthcare sites, 47% tested positive for influenza viruses.
  • Both influenza virus types A and B were co-circulating with a higher proportion (69%) of type A viruses detected.
  • The distribution of viruses detected varied between Member States and areas and within sub-regions. Although the majority of reported influenza virus detections across the Region were type A, 2 Member States reported influenza type B dominance and 4 Member States and areas reported co-dominance of types A and B viruses.
  • In the majority of specimens from severe cases admitted to ICU and non-ICU hospital wards, influenza type A viruses were detected.
  • Pooled estimates of all-cause number of deaths from 21 countries or regions reporting to the EuroMOMO project indicated an increasing trend in mortality over recent weeks.
  • Data from the Influenzanet indicated that influenza activity in the community was high in 1 reporting country, medium in 3 reporting countries and low in 4 reporting countries.

Other news

There is an ongoing outbreak of respiratory illness, with a significant increase in geographic spread, linked to a novel coronavirus first identified in China. For more information see:

2019/20 season overview 

  • For the Region as a whole, influenza activity commenced earlier than in recent previous years.
  • Influenza activity in the Region, based on sentinel sampling, first exceeded a positivity rate of 10% in week 47/2019 and has remained over 10% for 10 weeks. There has been an overall increasing trend in the weekly positivity rate for influenza virus detections among sentinel ILI surveillance patients, following a dip in week 52.
  • In sentinel sources, both influenza A virus subtypes, A(H1N1)pdm09 and A(H3N2), are co-circulating, 58% and 42%, respectively. Increased influenza virus subtype A(H1N1)pdm09 detections have been reported since week 50/2019. Of the influenza B viruses, the vast majority (98%) have been B/Victoria lineage.
  • Among hospitalized influenza virus-infected patients admitted to ICU wards since the beginning of the season, influenza type A viruses have been detected in the majority of cases (94%); of these 58% were A(H3N2) viruses. The same was reported for patients admitted to other wards, with 94% of cases being infected with type A viruses; of these 65% were A(H3N2) viruses.
  • Among SARI cases, influenza type B viruses were detected most frequently (57%).
  • Circulating viruses remain susceptible to the neuraminidase inhibitors supporting early initiation of treatment or prophylactic use according to national guidelines.
  • The effectiveness of vaccines in the population will be evaluated by vaccine effectiveness studies when there is are sufficient number of enrolled patients. Member States should continue encouraging influenza vaccination.
  • ECDC and WHO Regional Office published a joint Regional Situation Assessment for the 2019–2020 influenza season up to week 49/2019, which focused on disease severity and impact on healthcare systems to assist forward planning in Member States.

Influenza intensity, spread and dominant virus type/subtype