Dies ist eine HTML Version eines Anhanges der Informationsfreiheitsanfrage 'Infectious Diseases'.



 
 
 
 
 
TESSy - The European 
 
Surveillance System 
 
 
 
 
 
 
 
Influenza Reporting Protocol 2018 
 
Seasonal influenza 
 
 
 
December 2018 


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Introduction 
Contents 
Introduction ............................................................................................................... 4 
How to use this document ..................................................................................................... 4 
Finding further information .................................................................................................... 4 

Reporting to TESSy .................................................................................................... 5 
Checking the data collection schedule .................................................................................... 5 
Preparing data ...................................................................................................................... 5 
Checking metadata ............................................................................................................... 5 
Checking your data source profile .......................................................................................... 6 
Submitting your data ............................................................................................................ 6 
Finalising your submission ..................................................................................................... 6 
TESSy HelpDesk ................................................................................................................... 7 
Annex: Influenza metadata ......................................................................................... 8 
Influenza record types .......................................................................................................... 8 
Current record type versions ............................................................................................. 8 
Influenza antiviral susceptibility strain-based (INFLANTIVIR) .............................................. 8 
Influenza clinical data (ILI/ARI) weekly aggregate (INFLCLINAGGR) ................................... 9 
Severe acute respiratory infections (SARI) case-based (INFLSARI) .................................... 12 
Severe acute respiratory infections (SARI) weekly denominator (INFLSARIDENOM) ........... 14 
Severe acute respiratory infections (SARI) aggregate (INFLSARIAGGR) ............................. 15 
Virological weekly data (INFLVIRWAGGR) ........................................................................ 16 
 
 
 
 
© ECDC December 2018 All rights reserved. 
 
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Influenza Reporting Protocol 2018 
 
Introduction 
Introduction  
Since 2014, influenza surveillance in Europe has been jointly coordinated by the WHO Regional Office 
for Europe and ECDC. 
Surveillance data from the 53 countries of the WHO European Region, which include the 28 countries 
of the European Union (EU) and the additional three countries of the European Economic Area (EEA), 
are submitted to a joint ECDC/WHO database hosted in the European Surveillance System (TESSy). 
The purpose of this protocol is to provide instructions for the weekly reporting of influenza 
surveillance data during the influenza season (week 40 to week 20 of the following year) and the 
interseason. The protocol covers the contents of reporting these data to TESSy, including the case 
definitions, the population under surveillance and the timing of reporting. 
ECDC’s Reporting Protocols are part of the ECDC Surveillance Protocol, which is currently under 
preparation.  
The Reporting Protocols are supplemented by the TESSy Technical Annex, which contains updated 
generic information for each data collection. 
How to use this document 
This Reporting Protocol provides the following information:  
•  Reporting to TESSy – contains guidelines on how to prepare data for submission to TESSy, 
deadlines for data submission, subject-specific information, and links to further information.  
•  Annex – contains information on the influenza record types.  
Finding further information  
 Paragraphs denoted by the information icon tell where you can find further information.  
Updated links to all the schedules, documentation and training materials mentioned in this Reporting 
Protocol are included in the Technical Annex, including:  
• 
Metadata sets and history.  
• 
Tutorials for data transformation using respectively Excel and Access.  
• 
TESSy user documentation.  
• 
CSV and XML transport protocols.  
 
Page 4 of 16 



Influenza Reporting Protocol 2018 
 
Reporting to TESSy 
Reporting to TESSy  
This section provides both an overview of the TESSy reporting process and tips on where you can 
find useful information.  
The overall process is:  
1.  Familiarise yourself with the data collection deadlines.  
2.  Prepare (export and transform) your data.  
3.  Check that your data comply with the metadata.  
4.  Check that your data source profile is up-to-date.  
5.  Submit your file(s) to TESSy.  
6.  Finalise and approve your submission.  
Checking the data col ection schedule 
 An updated link to the current data collections schedule is provided in the Technical Annex.  
Preparing data 
After data are exported from a national database, the data submitter needs to ensure that the data 
are in a format that TESSy can accept. This applies both to the type of file submitted to TESSy (only 
CSV and XML files can be submitted) and to the format of the data in certain fields.  
 Tutorials covering how you can transform your data to the correct TESSy format using Excel or 
Access are available on the TESSy documents website. Information on the file formats is available in 
the CSV Transport Protocol and XML Transport Protocol.  
Checking metadata 
The TESSy metadata define the fields and data formats that are valid as input to TESSy for a given 
subject.  
As the requirements to the data that are shared among TESSy users change, the data changes 
needed to support the new requirements are identified and agreed upon between the National 
Surveillance Contact Points, the Network Coordination Groups and ECDC’s and WHO’s Disease 
Experts, and then implemented as changes to the TESSy metadata.  
In order to ensure that your data can be saved correctly in TESSy, you therefore need to check that 
your data are correctly formatted according to the most recent metadata set.  
Changes to the metadata for the subject of this Reporting Protocol are described in:  
• 
Changes to current metadata – changes since the last Reporting Protocol.  
• 
Annex 1 Metadata change history – all preceding changes.  
It is especially important to focus on:  
• 
Field formats  
Many fields require that data are formatted in a specific way. For example, dates must be in the 
YYYY-MM-DD format; dates in the DD/MM/YYYY format will be rejected.  
• 
Coded values   
Some fields only permit the use of specific values (coded values). For example, MFUNK, or 
Other are the coded values for Gender and any other value in a Gender field will be rejected.  
 
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Influenza Reporting Protocol 2018 
 
Reporting to TESSy 
The metadata file contains all the definitions and rules you need to comply with to format your data 
correctly for every subject (usually a disease). The file can be downloaded as an Excel file from the 
TESSy documents website.  
By filtering the fields in the file by subject, you can see the fields required for your subject and the 
rules applying to these fields.  
 The Technical Annex provides an overview of how you work with the metadata file, and the 
TESSy user documentation provides in-depth details on metadata.  
Checking your data source profile 
Before submitting your file(s), please review the profile for your data source(s) in TESSy (go to Data 
Sources
), and update the information, if necessary.   
  
Complete and up-to-date data source information for each subject is important for improving 
interpretation of data - each surveillance system has different features that need to be taken into 
account when comparing data at an international level.  
If your data source information is out-of-date and you do not have access rights to update it, please 
request your National Focal Point for Surveillance or National Coordinator to do so.  
 In-depth information on the data source variables is available in the TESSy user documentation.  
Submitting your data 
Data are submitted through the TESSy web interface (go to Upload).  
  
 The Technical Annex provides an overview of how you submit files to TESSy, and the TESSy user 
documentation provides in-depth descriptions of all the upload methods.  
Finalising your submission 
The compliance of your data with the validation rules in the metadata is checked automatically during 
the data upload process.  
The result of your upload – i.e. rejected or validated – is displayed immediately after the conclusion 
of the check in the Validation details webpage. Please review the result carefully:  
• 
If your file has been rejected, there will be a message explaining each instance of 
noncompliance with the metadata that you need to correct.  
• 
If your file has been validated, there might be warnings and remarks relating to possible 
data quality issues or to potential overwriting of existing records that you should consider. 
When your file has been validated and you are satisfied that all corrections have been made, 
please ensure prompt approval – unapproved uploads can block for the approval of 
other uploads.   
 The TESSy user documentation provides information on reviewing validation results and 
adjusting reporting periods to avoid overwriting existing records.  
 
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Influenza Reporting Protocol 2018 
 
Reporting to TESSy 
TESSy HelpDesk 
Email:  xxxxx@xxxx.xxxxxx.xx 
Telephone number:  +46-(0)8-5860 1601 
 
Availability: 9:00 – 16:00 Stockholm time, Monday to Friday (except ECDC Holidays) 
 
 
 
 
Page 7 of 16 

link to page 8 Influenza Reporting Protocol 2018 
 
Annex: Influenza metadata 
Annex: Influenza metadata 
This section describes the influenza metadata set.  
Influenza record types  
The influenza record types are:  
•  INFLANTIVIR - Influenza antiviral susceptibility strain-based, weekly  
•  INFLCLINAGGR - Influenza clinical data (ILI/ARI) aggregate, weekly  
•  INFLSARI - Severe acute respiratory infections (SARI) case-based, weekly  
•  INFLSARIDENOM - Severe acute respiratory infections (SARI) denominator, weekly   
•  INFLSARIAGGR - Severe acute respiratory infections (SARI) aggregate, weekly  
•  INFLVIRWAGGR - Virological data aggregate, weekly  
Current record type versions 
Table 1 shows the record type versions to be used when reporting influenza surveillance data to 
TESSy during the 2018-2019 season. 
Table 1. Influenza record version types for 2018-2019 season data 
Record 
Record type version 
INFLANTIVIR 
INFLANTIVIR.6 
INFLCLINAGGR 
INFLCLINAGGR.4 
INFLSARI 
INFLSARI.4 
INFLSARIDENOM 
INFLSARIDENOM.2 
INFLSARIAGGR 
INFLSARIAGGR.1 
INFLVIRWAGGR 
INFLVIRWAGGR.9 
Influenza antiviral susceptibility strain-based (INFLANTIVIR)  
The objectives of antiviral susceptibility surveillance of seasonal influenza viruses are:  
• 
To provide timely data on the antiviral susceptibility of influenza viruses and related amino 
acid substitutions, also enabling comparisons with previous seasons;  
• 
To monitor the distribution of influenza viruses associated with antiviral drug resistance;  
• 
To identify treatment courses associated with antiviral drug resistance;  
• 
To inform treatment guidelines.  
Case definition  
The influenza case definition is specified in the EU Commission Decision 2012/506/EU of 8 August 
2012.  
Specimens for antiviral susceptibility analysis are selected from the positive specimens detected from 
sentinel and non-sentinel sources. The specimens should be selected representing different subtypes 
 
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Influenza Reporting Protocol 2018 
 
Annex: Influenza metadata 
and according to age groups, geographic location and severity. Specimens both from untreated 
patients and from patients that receive antiviral treatment should be included. 
Virus strain-based data should be reported weekly during the influenza season (week 40 to week 20 
of the following year) and interseason (weeks 21-39). The metadata includes information on virus, 
demographics, source of specimen, hospitalisation, underlying conditions, vaccination status and 
treatment (see the TESSy metadata). The reporting of antiviral susceptibility data to TESSy includes 
also the strain-based reporting of the genetic clade and antigenic group to which the virus belongs.  
The antiviral susceptibility data can originate from two different sources; from testing in the own 
laboratory/country or from testing of viruses that have been submitted to the WHO Collaborating 
Centre (WHOCC), London, UK. Countries are asked to upload both data as soon as results are 
available. For both datasets a different DataSource variable should be used when uploading the data. 
For country data the DataSource has been defined by the country itself. The DataSource for WHOCC 
data is pre-set by ECDC and has the structure NN-CNRL_Influenza, where NN is the 2-letter ISO code 
for the country.   
Influenza clinical data (ILI/ARI) weekly aggregate (INFLCLINAGGR)  
The objectives of weekly epidemiologic surveillance of seasonal influenza infections (influenza-like 
illnesses (ILI) and acute respiratory infections (ARI)) in primary care facilities during weeks 40 and 20 
are:  
• 
To estimate the intensity of ILI/ARI rates in the community;  
• 
To compare this intensity to previous seasons and to other countries with similar 
denominators and case definitions;  
• 
To identify most affected age groups.  
Case definition  
Any person with at least one of the following clinical forms:  
Influenza-like illness (ILI)  
Sudden onset of symptoms  
AND  
at least one of the following four systemic symptoms: fever or feverishness, malaise, headache, 
myalgia  
AND  
at least one of the following three respiratory symptoms: cough, sore throat, shortness of breath.  
Acute respiratory infection (ARI)  
Sudden onset of symptoms  
AND  
at least one of the following four respiratory symptoms: cough, sore throat, shortness of breath, 
coryza  
AND a clinician's judgement that the illness is due to an infection.  
ILI is clinically more specific for influenza-infection than ARI, which encompasses all infections of the 
upper respiratory tract. Some come countries report both clinical data.  
The covered population is variable, making comparisons between countries difficult or impossible: in 
some countries, sentinel general practitioners have a determined list of patients or an averaged 
number of weekly patients, and in these countries the denominators can be calculated for 100.000 
inhabitants. Some countries calculate the number of cases by physician or by the number of 
consultation for ILI or ARI. In countries with discrepant definitions, only trends over time may be 
used.  
 
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Influenza Reporting Protocol 2018 
 
Annex: Influenza metadata 
The sentinel physicians report the weekly aggregated number of ILI and /or ARI numbers by four age 
groups (0-4, 5-14, 15-64, ≥ 65 years old, unknown and total) with a denominator for each age 
group.  
In addition to clinical indictors, qualitative indicators are also reported:   
•  Intensity  
•  Geographic spread  
•  Trend  
•  Dominant type 
•  Impact  
Intensity 
The intensity indicator is a measure of influenza activity within individual Member States.  
  Baseline or below epidemic threshold: ILI or ARI rates that are very low and at levels usually 
seen throughout the inter-epidemic period.  
  Low: ILI or ARI rates that are relatively low compared to rates from historical data but higher 
than the baseline. Influenza virus detections have been reported. 
  Medium: ILI or ARI rates that are similar to rates usually observed, based on historical data. 
Influenza virus detections have been reported.  
  High intensity: ILI or ARI rates that are higher than rates usually observed, based on 
historical data. Influenza virus detections have been reported.  
  Very high: ILI/ARI rates that are much higher than rates usually observed, based on historical 
data. Influenza virus detections have been reported.  
Intensity level can be defined using two approaches: 
a) Qualitative indicator based on a national expert evaluation of intensity. For Member States that 
report intensity as a qualitative indicator using an expert evaluation of intensity, they can do so by 
reviewing the weekly ILI or ARI rates and comparing them to rates in previous seasons. It is 
recommended to take influenza virus detections into account as well. 
b) Semi-quantitative indicator using historical data (e.g. MEM, WHO or other methods). For Member 
States that report intensity as a semi-quantitative indicator, they can do so by a predefined method. 
It is recommended to take influenza virus detections into account as well as syndromic data. 
Geographic spread 
Geographic spread is a measure for the geographic distribution of reported detections of influenza 
viruses in specimens from sentinel or non-sentinel sources.  
  No activity: No influenza viruses detected (other than detections from cases with recent 
known history of travel).  
  Sporadic: Influenza viruses sporadically detected.  
  Local(ised): Circulation of influenza viruses limited to one administrative unit in the MS (or 
reporting site). 
  Regional: Circulation of influenza viruses appearing in multiple but less than 50% of the 
administrative units of the MS (or reporting sites)*.  
  Widespread: Circulation of influenza viruses appearing in 50% or more of the administrative 
units of the Member State (or reporting sites).  
*Regional activity is generally not used for Member States with a small population (<5 M) and 
covering a small geographic area. 
Trend 
 
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Influenza Reporting Protocol 2018 
 
Annex: Influenza metadata 
Trend indicator is a measure of changes in ILI and/or ARI rates and lab-confirmed influenza cases in 
comparison to the previous week or weeks.  
  Increasing: ILI and/or ARI consultation rates are substantially higher compared to the 
previous week(s) and influenza viruses must have been detected in specimens from sentinel 
and/or non-sentinel sources a,b. 
  Stable: ILI and/or ARI consultation rates are similar compared to the previous week(s). 
Influenza viruses must have been detected in specimens from sentinel and/or non-sentinel 
sources b.  
  Decreasing: ILI and/or ARI consultation rates are substantially lower compared to the 
previous week(s). Influenza viruses must have been detected in specimens from sentinel 
and/or non-sentinel sources a,b.  
a Multiple prior weeks should be used to assign increasing or decreasing trend when intensity is “No 
activity or below epidemic threshold” and in the absence of such evidence default to stable;  
b Sentinel data are preferred but if these are not available non-sentinel data may be used. 
Dominant type 
Dominant virus reports on the dominant influenza virus type and/or subtype/lineage in the MS. 
• 
The dominant influenza virus type, subtype or lineage is reported when 10 or more influenza-
positive results per week (or weeks) are available, with the type (A or B) defined as a minimum 
return. The threshold for dominance is set at 60% and the threshold for co-dominance is set between 
40% and 60%. The report of subtypes or lineage also requires a minimum of 10 positive viruses sub-
typed or ascribed to a lineage. 
• 
We advise Member States to base their dominant type on sentinel data, where possible. 
These are generally from sentinel primary care facilities and best represent the circulation of influenza 
in the community. Where a Member State does not have data from sentinel sources, data from non-
sentinel sources can be used to determine the dominant influenza type. 
Impact 
Impact is a measure of resultant hospitalization of the epidemic within individual Member States.  
  Baseline: influenza related hospitalizations (SARI or laboratory confirmed hospitalizations, as 
counts, percentage positivity or rates) at levels usually seen throughout the inter-epidemic 
period.  
  Low:  influenza related hospitalizations (SARI or laboratory confirmed hospitalizations, as 
counts, percentage positivity or rates) that are relatively low compared to rates from 
historical data but higher than the baseline.  
  Medium:  influenza related hospitalizations (SARI or laboratory confirmed hospitalizations, as 
counts, percentage positivity or rates) that are similar to rates usually observed, based on 
historical data.  
  High:  influenza related hospitalizations (SARI or laboratory confirmed hospitalizations, as 
counts, percentage positivity or rates) that are higher than rates usually observed, based on 
historical data.  
  Very high: influenza related hospitalizations (SARI or laboratory-confirmed hospitalizations, as 
counts, percentage positivity or rates) that are much higher than rates usually observed, 
based on historical data. 
 
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Influenza Reporting Protocol 2018 
 
Annex: Influenza metadata 
Severe acute respiratory infections (SARI) case-based (INFLSARI) 
The objectives of hospital surveillance of seasonal influenza are:  
• 
To provide timely data on the severity and burden of more severe influenza, also enabling 
comparisons with previous seasons;  
• 
To monitor the distribution of influenza viruses associated with severe clinical presentations;  
• 
To identify underlying conditions associated with severe influenza;  
• 
To detect what factors and interventions seem to protect against severe disease.  
Case-based data should be reported weekly during the influenza season (week 40 to week 20 of the 
following year). The metadata includes information on demographics, type of hospitalisation, 
underlying conditions, vaccination status and treatment (see TESSy metadata).  
Case definition  
Both laboratory-confirmed influenza requiring hospitalisation and severe acute respiratory infection 
(SARI) can be reported.  
 
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Influenza Reporting Protocol 2018 
 
Annex: Influenza metadata 
Laboratory-confirmed hospitalised influenza case  
A severe influenza case is defined as a person with laboratory-confirmed influenza infection requiring 
overnight hospitalisation. According to the EU case definition, a laboratory-confirmed influenza 
infection is a person meeting the clinical definition of ILI or ARI and at least one of the following 
laboratory criteria for case confirmation:  
• 
Isolation of influenza virus from a clinical specimen;  
• 
Detection of influenza virus nucleic acid in a clinical specimen;  
• 
Identification of influenza virus antigen by direct fluorescence antibody test in a clinical 
specimen;  
• 
Influenza-specific antibody response.  
An emergency room consultation without hospitalisation is not considered an admission.  
 
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Influenza Reporting Protocol 2018 
 
Annex: Influenza metadata 
Severe acute respiratory infection (SARI)  
An acute respiratory illness with onset during the previous 7 days requiring overnight hospitalization 
that includes:  
• 
History of fever or measured fever of ≥ 38°C, AND  
• 
Cough, AND  
• 
Shortness of breath or difficulty breathing.  
This also includes any health care-acquired influenza infections.  
Population under surveillance  
Countries select sentinel acute care hospitals that are willing to participate and have the capacity to 
do so. In certain Member States, all hospitals may participate, if feasible. In these sentinel sites, all 
laboratory-confirmed hospitalised influenza or SARI cases are reported. The data are then transferred 
to the national public health authority in charge of influenza surveillance from where the nominated 
influenza contact point reports them to ECDC.  
Sentinel sites have to be carefully selected, taking into account the balance between urban/rural 
areas, broad geographical coverage in a country, priorities in the national plan for hospital 
preparedness, etc. The denominator (hospital catchment population) should be defined (see 
Virological weekly data (INFLVIRWAGGR)).  
Severe acute respiratory infections (SARI) weekly denominator 
(INFLSARIDENOM)  
Several options may be used to determine the proportion of the population covered by the selected 
sentinel hospitals:  
1.  If the information on the hospitals’ catchment population is available, it should be provided 
directly.  
2.  If the information on hospitals’ catchment population is not available, it should be estimated. Two 
approaches to calculating denominators are provided below.  
a)  Estimate  based  on  the  number  of  patient  discharges  from  the  previous  year:  proportion  of 
patients  discharged  from  the  selected  hospitals  divided  by  the  total  number  of  patients 
discharged from all hospitals in the Member State.  
b)  Estimate based on the number of beds: in an urban area, the catchment population can be 
estimated by taking into account the population of the city, the number of hospitals in the city 
and the number of beds in a hospital. Coefficients should be attributed to each hospital in the 
city depending on their activity estimated by the number of beds. For example, in a city with 3 
hospitals, if hospital A has 50 beds, the coefficient to be applied will be 0.5, if hospital B has 
125 beds, the coefficient will be 1.25 and if hospital C has 75 beds, the coefficient will be 0.75, 
so:  
Catchment population = City population*coefficient (based on the number of beds)/Number 
of hospitals in the city.   
In this approach, the estimation of population coverage of hospitals should first be done for 
each hospital and estimates from hospitals should be summed up, so that the estimates 
apply to the full surveillance system.  
 
 
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Influenza Reporting Protocol 2018 
 
Annex: Influenza metadata 
Severe acute respiratory infections (SARI) aggregate (INFLSARIAGGR)  
For countries unable to report case-based data for severe influenza, this record type allows the 
reporting of aggregate data (total and by age group) for:  
• 
Sentinel SARI hospitalisations (numerator);  
• 
Sentinel SARI hospitalisation deaths (numerator);  
• 
Sentinel hospitalisations admissions (denominator);  
• 
Sentinel hospitalisations population (denominator);  
• 
Sentinel SARI specimens tested (denominator);  
• 
Sentinel SARI specimens tested positive for influenza viruses (numerator)  
  
  
 
 
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Influenza Reporting Protocol 2018 
 
Annex: Influenza metadata 
Virological weekly data (INFLVIRWAGGR)  
The objectives for virological surveillance are:  
• 
To collect and provide timely information on the distribution of types, subtypes, lineages and 
clades among circulating influenza viruses over the influenza season.  
• 
Early warning upon emergence of new subtypes.   
• 
To assess the start of the influenza season.  
• 
To monitor the intensity and geographic progression of influenza throughout the season   
• 
Inform public health preparedness in Europe, especially in countries not yet affected by 
widespread influenza epidemics, and trigger operational plans (e.g. use of antivirals and 
personal protective measures).  
• 
To inform WHO vaccine composition meeting.  
Aggregated virological data should be reported weekly during the influenza season (week 40 to week 
20 of the following year). The metadata includes information on virus detection by (sub-)type from 
sentinel and non-sentinel sources, number virus (sub-)types isolated by sentinel and non-sentinel 
sources and characterisation of viruses by genetic and antigenic methods. In addition to influenza, 
respiratory syncytial virus (RSV) detections can also be reported from sentinel and non-sentinel 
sources (see TESSy metadata).   
The characterisation data of viruses should preferably be reported via the strain-based reporting in 
the INFLANTIVIR record type (see Influenza antiviral susceptibility strain-based (INFLANTIVIR)). 
The aggregate reporting for characterisation data should only be used if the country does not have 
resources for strain-based reporting.  
The virological data are entered in the week that the swab was taken (by week of sampling).  
One virus detection corresponds to the detection of influenza in one patient, regardless of the 
number of specimens taken from that patient, or which technique(s) were used to detect the virus.   
Case definition  
The influenza case definition is specified in the EU Commission Decision 2012/506/EU of 8 August 
2012.  
Population under surveillance  
Virological surveillance can be either sentinel or non-sentinel. Surveillance is considered sentinel when 
virological testing is performed in the same population in which clinical cases are recorded and 
reported taking a country-wide representative collection scheme into account. The virological 
surveillance of laboratory-confirmed influenza and RSV in Europe uses the same primary healthcare 
sentinel network model as the syndromic surveillance of ILI/ARI. The catchment population of the 
sentinel physicians forms the main population under surveillance. Patients with ILI/ARI (or a subset 
of these patients) seen by a sentinel physician are swabbed according to a defined sampling protocol. 
The virological surveillance system also captures non-sentinel detections of influenza virus, but the 
non-sentinel population under surveillance is not defined in all Member States. Virological data from 
non-sentinel sources can be from patients presenting at outpatient or inpatient health care facilities, 
outbreak investigations and as part of enhanced surveillance, for example as performed by countries 
during the early stages of the pandemic.   
 
 
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