Week 19/2016 (9-15 May 2016)
- Influenza activity continued to decrease in the WHO European Region. Most countries (95%) reported low intensity. The percentage of positive specimens and the absolute number of influenza virus detections decreased from the previous week.
- Type B viruses accounted for 95% of influenza detections in specimens from sentinel sources and 72% from non-sentinel sources.
- Few cases of severe disease were reported from intensive care units (ICUs). Most severe cases were associated with A(H1N1)pdm09 infection and were in people aged 15–64 years.
- This season, influenza A(H1N1)pdm09 viruses have predominated in most countries in the Region. As is often seen late in the northern hemisphere’s influenza season, a shift towards circulation of type B influenza virus has occurred, with type B dominating since week 09/2016 in specimens from sentinel sources.
- Influenza activity, based on laboratory-confirmed mild and severe cases in sentinel and non-sentinel sources, peaked in weeks 05–07/2016. The countries first affected were in general located in the eastern part of the Region.
- Data from the 18 countries or regions reporting to the European monitoring of excess mortality for public health action (EuroMOMO) project suggested a pattern of excess all-cause mortality among those aged 15–64 years between the end of 2015 and week 14/2016. This may have been associated with influenza, as well as other factors. The level of excess all-cause mortality was similar to that of the 2012–2013 winter season and slightly lower than that of the 2014–2015 winter season.
- Most of the viruses genetically characterized so far have been similar to those recommended for inclusion in the trivalent or quadrivalent vaccines for the 2015–2016 influenza season in the northern hemisphere.
- The vast majority of the viruses genetically and/or phenotypically characterized so far shows no indications of reduced susceptibility to the neuraminidase inhibitors oseltamivir and zanamivir.
- Recommendations on the composition of the seasonal influenza vaccines for the 2016–2017 season in the northern hemisphere call for replacement of the A(H3N2) component with a more recent virus and inclusion of a B/Victoria-lineage virus in trivalent vaccines.
- Risk assessments for the season are available from the European Centre for Disease Prevention and Control (ECDC) and the WHO Regional Office for Europe websites.
Additional information on influenza in the world is available from WHO’s global updates.
Due to a technical problem, please note that the data reported for sentinel, non-sentinel detections, genetic characterisation and hospital data in the bulletins weeks 16 to 18 were incorrect.
Influenza intensity, spread and dominant virus type/subtype
Influenza virus detections in the region