Influenza season in EU/EEA countries 2014/15 presented at the annual European Influenza Surveillance Network meeting, Stockholm, June 2015

1. Influenza season 2014-2015
in EU/EEA countries
R. Snacken, C. Adlhoch and E. Broberg
Stockholm, 10 June 2015

2. Intensity by country and by week
EU/EEA - 2014/152014
W40
2014
W41
2014
W42
2014
W43
2014
W44
2014
W45
2014
W46
2014
W47
2014
W48
2014
W49
2014
W50
2014
W51
2014
W52
2015
W01
2015
W02
2015
W03
2015
W04
2015
W05
2015
W06
2015
W07
2015
W08
2015
W09
2015
W10
2015
W11
2015
W12
2015
W13
2015
W14
2015
W15
2015
W16
2015
W17
2015
W18
2015
W19
2015
W20
Austria
Belgium
Bulgaria
Croatia
Cyprus
Czech
Republic
Denmark
England
Estonia
Finland
France
Germany
Greece
Hungary
Iceland
Ireland
Italy
Latvia
Lithuania
Luxembourg
Malta
Netherlands
Northern
Ireland
Norway
Poland
Portugal
Romania
Scotland
Slovakia
Slovenia
Spain
Sweden
Wales Low
Medium
High
Very High
Unknown
First countries reporting medium intensity

3. Peak intensity of influenza activity
EU/EEA - 2014/15
Low intensity was reported by:
Cyprus
Denmark
Poland

4. Influenza viruses (sub)-types by week
EU/EEA - 2014/15
Positivity rate > 10% during 22 weeks
Number of
specimens tested
for influenza
Positivity
rate (%)

5. Influenza viruses (sub)-types by week
EU/EEA - 2014/15
Week 52 Week 08
Week 05
Week 04
Week 07
>10% positivity indicating influenza activity: 20-21 weeks
Week 44
Peak week
Duration of positivity rate > 10%

6. Influenza-positive sentinel specimens by
season and (sub-)type, EU/EEA 2008-2015
A(H3) B/Yam -
A(H1)pdm09
A(H1)pdm09
- A(H3)
A(H1)pdm09 –
B/Vic
Variability in dominant and co-circulating virus types and subtypes
A(H3) –
B/Yam
2010/11 2011/12 2012/13 2013/14 2014/152009/102008/09
A(H1)pdm09A(H3) –
B

7. Dominant virus types season 2014/15,
EU/EEA
Sentinel system
Dominant: >60%

8. RSV detections by season in 21 EU/EEA
countries, 2013/14 and 2014/15
week
Number of
detections
0
500
1000
1500
2000
2500
3000
40 41 42 43 44 45 46 47 48 49 50 51 52 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
RSV in EU 2013/14
2014/15

9. Genetic characterisation
Phylogenetic group
Number of
viruses
A(H1N1)pdm09 A/South Africa/3626/2013 (subgroup 6B)1 266
A(H1N1)pdm09 A/St Petersburg/27/2011 (group 6)1 6
A(H3N2) A/Texas/50/2012 (subgroup 3C.1)1 10
A(H3N2) A/Stockholm/1/2013 (subgroup 3C.2)1 2
A(H3N2) A/Hong Kong/5738/2014 (subgroup3C.2a)2 606
A(H3N2) A/Samara/73/2013 (subgroup 3C.3)1 300
A(H3N2) A/Switzerland/9715293/2013 (subgroup 3C.3a)2 65
B/Phuket/3073/2013 (Yamagata lineage clade 3) 364
B/Wisconsin/1/2010 (Yamagata lineage) 3
B/Brisbane/60/2008 (Victoria lineage) 9
1 Genetic group containing viruses with antigenic properties similar to the 2014–2015 vaccine virus
2 Genetic group containing viruses with antigenic properties dissimilar to the 2014–2015 vaccine virus

10. Antiviral resistance, EU/EEA 2014/15
Virus
type and
subtype
Resistance to neuraminidase inhibitors
Resistance to M2
blockers
Oseltamivir Zanamivir
Isolates
tested
Resistant %
Isolates
tested
Resistant %
Isolates
tested
Resista
nt
%
A(H3N2) 1 535 4 0.3 1 524 1 <0.1 244 244 100
A(H1N1)
pdm09
566 2 0.4 560 0 0 84 84 100
B 515 0 0 510 0 0 NA1 NA NA
1 NA: Not applicable

11. ICU cases by (sub)type and age-group
in eight EU countries
Higher proportions of ICU admission in > 40 years and older
Number of
ICU cases
Number of
ICU cases

12. Number of influenza-related fatalities by (sub)type
and age-group in hospitals (all wards)

13. Excess mortality
among the elderly
in 13 EU countries
Mølback K. et al. EuroSurv 2015; 20(11):pii=21065
excess mortality from all causes concomitant with influenza activity

14. Conclusions 2014-2015
• Start of the season, intensity and duration in primary care settings similar
to previous seasons
• Large dominance of A(H3N2) viruses in almost all countries
• Increasing dominance of B viruses when circulating A(H3N2) viruses
declined
• Antigenic and genetic drift of A(H3N2) resulting in very low vaccine
effectiveness
• Very low percentage of A viruses showing a reduced susceptibility to Nis
• Most affected age-groups in hospitalised cases were infected by A(H3N2)
virus
• Substantial excess mortality from all causes concomitant with influenza
activity in 13 reporting EU countries

15. Thanks to all members of EISN
Thanks to WHO Regional Office Europe
for the fruitful collaboration