Presentation by Eeva Broberg and Cornelia Adlhoch of ECDC at the Joint WHO/Europe & ECDC Annual Influenza Surveillance Meeting, Vienna, Austria, 11–13 June 2014.

1. Update of influenza metadata
Joint WHO/Europe & ECDC Annual Influenza Surveillance Meeting
Vienna, 11-13 June 2014
Eeva Broberg and Cornelia Adlhoch, ECDC
Special thanks to: Neli Korsun (BU), Martina Havlíčková (CZ), Ramona Trebbien
(DK), Niina Ikonen (FI), Vincent Enouf (FR), Istvan Jankovics (HU), Natalija
Zamjatina (LV), Adam Meijer (NL), Karoline Bragstad (NO), Karolina Bednarska
(PL), Raquel Guiomar (PT), Emilia Lupulescu (RO), Helena Dahl (SE), Katarina
Prosenc (SI) and Edita Staronova (SK)

2. Principles
1. Do not collect data if it is not used
2. Collect data for action
3. Use data to set priorities for the
use of resources
Analysis
InterpretationAction
Data collection

3. Serology
• Objective has been to provide detections by serology, e.g. for
cases with prolonged symptoms
• High numbers from non-sentinel, very few data from sentinel
surveillance
• 7 - 9 countries reporting, in 2013-2014 AT, BG, FR, LV, NO, SK and
UK

4. Serology vs. detections
• Seasonality detected also through serology
• All aggregated data, e.g. no age groups available
• How should the data be used?
– Should we focus rather on serosurveys?
– What should be the timeline of reporting?
– How should we analyse and interpret the data?

5. Country comments on serology
• Serology used when more time has elapsed since
onset of disease
• Used only upon request of a clinician
• For detections IgM, IgA and IgG ELISA tests in use
(e.g. Euroimmun)
• In some countries, not possible to differentiate
between sentinel and nonsentinel
• Weekly data across countries from various
laboratories
• Some countries perform serosurveys but TESSy does
not capture age-groups

6. Serology variable completeness
• A proposal:
– RSV serology variables to be inactivated

7. Isolation
• No denominator variable available
• Data collection started as a project for vaccine candidate selection
• In general, few isolations reported, 5-8 countries per season, in 2013-2014
only CZ, FI, PT, SE and SK
• How should these variables be used?

8. Egg isolation variables
• No denominator
• 21 specimens by 3 countries over 2 seasons
• A proposal: all egg isolation variables to be
inactivated

9. Country comments on isolations
• Selection of samples based on Ct value of RT-PCR / severity /
subtypes / time of season / travel history / variant strains /
resistant strains / vaccine failures
• “Expertise test”, obligation of NIC
• Production of good quality viral RNA for sequencing
• Needed for vaccine composition and phenotypic
characterisation
• Egg isolation rarely used, some use only for animal strains
• Important to retain the geographic distribution of data
throughout the European Region
• A(H1N1)pdm09 has not been added to isolation variables
separately

10. Strain-based reporting
• Collection of antiviral susceptibility, antigenic
and genetic characterisation data
• No denominator data available as not all
countries report “negative” results
• Can we agree on a characterisation algorithm?

11. Courtesy of Natalia Zamjatina, Latvian Centre of Infectious Diseases , National Microbiology Reference Laboratory, NIC of Latvia.

12. Questions
1. Should we keep or inactivate RSV serology variables?
2. How should the serology variables be best used?
3. Should we keep influenza virus isolation variables for weekly reporting,
or should we consider an end/of/season reporting? Should we keep or
inactivate the influenza egg isolation variables?
4. What would be the denominator data for isolations and should such
aggregate variable be added?
5. Should we add denominator variable for the influenza antiviral
susceptibility testing and characterisations in aggregate reporting?
6. Do we need to add variables to strain-based data?
a. Isolated? Yes/No
b. Sent to WHO CC? Yes/No
c. Streamline with GISAID variables?
7. Volunteers to be in a metadata reference group?