Estimated number of influenza/flu-like illnesses/100,000 population per calendar week, Austria, KW 40-15, 2021/2022
|week||Season 2021/2022||Season 2020/2021||Season 2019/2020|
Estimated number of influenza/illness-like illnesses (ILI)/100,000 population by age group and by week, Austria, week 40-15, 2021/2022
|week||Incidence 0-4 years||Incidence 5-14 years||Incidence 15-64 years||Incidence 65+ years|
Estimated number of influenza/illness-like illness (ILI)/100,000 population, reported ARI-related sick leave/100,000 eligible insured/employed persons as of CW, CW 40-15, 2021/2022
|week||ARI sick leave OÖGKK||ILI all age groups||ILI 15-64 years|
Number of laboratory-confirmed cases of influenza A, influenza B, and estimated number of influenza/flu-like illnesses/100,000 population per week, Austria, weeks 40-15, 2021/2022
|Week||laboratory confirmed cases Influenza A||laboratory confirmed cases Influenza B||ILI|
Number of laboratory-confirmed cases by influenza virus type/subtype and percent of influenza samples testing positive among sentinel samples tested per KW, Austria, KW 40-15, 2021/2022.
|Week||Influenza B Case||Influenza A(H1N1)pdm09 Case||Influenza A/H3N2 Case||Influenza A case, other Subtype||Influenza A case, not subtyped||Positivity-Rate (positive samples/examinated samples)|
Data source for Figs. 1 and 2: Estimated ILI/100,000 inhabitants is an estimate based on data from the influenza reporting system of MA 24- Landessanitätsdirektion der Stadt Wien, Dept. 7, Stadt Graz, as well as ILI data from the greater Innsbruck area
Data source for Fig. 3: Insurance data: from KGKK (ICD diagnoses for ARI) and OÖGKK. eligible insured from ÖOGKK: employed, PD, KBG eligible insured from KGKK: employed, unemployed, KRG, KBG and voluntary insured
Data source for Fig. 4: Virological sentinel surveillance system (DINÖ): National Reference Laboratory for Influenza, Department of Virology; Medical University of Vienna; Virological non-sentinel surveillance system: Section of Virology, Department of Hygiene, Microbiology, Social Medicine; Med. University IBK, Tyrol; Department of Virology & Infectious Serology, Institute of Hygiene, Microbiology, and Environmental Medicine Med. University Graz, Stmk; Microbiological Laboratory & Joint Practice for Travel Medicine, IBK, Tyrol; Analyse BioLab GmbH, Elisabethinen Linz, Upper Austria; SALK Labor GmbH, Salzburg; Institute for Medical, Microbiology and Hygiene at the Klinikum Wels-Grieskirchen, Upper Austria
The Austrian Reference Centre for Influenza Epidemiology at the Institute of Medical Microbiology and Hygiene Vienna is responsible for recording the epidemiological situation of influenza in Austria on the basis of a clinical and a virological sentinel surveillance system as well as laboratory reports of influenza virus detections from a further six virological laboratories.
At weekly intervals, the estimated weekly incidence of ILI (influenza like illness) is calculated and published on the AGES homepage Influenza since the beginning of the 2009/2010 season. The data originate from the sentinel ILI surveillance system established since 1992/1993, which consists of the influenza information system of Magistrate 15 of the City of Vienna, the influenza information system of Dept. 7 of the City of Graz and the influenza surveillance system Greater Innsbruck. Since the beginning of 2012, ILI case data from all three influenza information systems Vienna, Graz and Innsbruck are processed once a week by the Reference Centre for Influenza Epidemiology and sent to the Federal Ministry of Social Affairs, Health, Care and Consumer Protection (BMSGPK) for transmission to TESSy (The European Surveillance System) and from TESSy to WHO/EuroFlu.
In 1992/93, the ILI (influenza-like illness) sentinel system was established: 52 registered volunteer reporting physicians (general practitioners and paediatricians) from the influenza information systems of Magistrate 15 of the City of Vienna and Dept. 7 of the City of Graz as well as the influenza surveillance system of the Innsbruck area report weekly the cases of ILI identified within one working week according to the definition of influenza-like illness (ILI) to the Reference Centre for Influenza Epidemiology. Here, the estimated incidence per calendar week is calculated at weekly intervals (number of reported cases per number of inhabitants of the patient catchment area of the reporting physician).
Virological surveillance is performed by the virological sentinel system DINÖ (Diagnostic Influenza Network Austria), coordinated by the National Reference Laboratory for Influenza Viruses at the Centre for Virology of the Medical University of Vienna. 98 sentinel physicians (= reporting physicians) send nasopharyngeal swabs of ILI cases to the National Reference Laboratory for Influenza every week for testing. The weekly number of specimens tested for influenza and the number of specimens with influenza virus detection are sent by the National Reference Laboratory to the Reference Centre for Influenza Epidemiology.
Another five influenza diagnosing laboratories (Section of Virology, Dep. of Hygiene, Microbiology, Social Medicine; Med. University IBK, Tyrol, Department of Virology; Infectious Serology, Institute of Hygiene, Microbiology, and Environmental Medicine; Medical University Graz, Microbiological Laboratory; Joint Practice for Travel Medicine, IBK, Tyrol, Analyse BioLab GmbH; Companies of Elisabethinen Linz and AGES, Upper Austria, SALK Labor GmbH, Salzburg) also report once a week the weekly number of samples with influenza virus detection according to virus type or subtype as well as the number of samples tested for influenza. Subtyping of circulating influenza viruses performed by the National Reference Laboratory is used to detect the emergence of new influenza virus variants and to compare them with the strains contained in the current vaccine. The aim of the Austrian Influenza Surveillance System is to monitor influenza activity in order to detect seasonal as well as inter-seasonal influenza epidemics at an early stage.
As influenza is often not recognized or registered as a cause of death, it is international standard that influenza-related deaths are estimated by modelling. Such a model was established in Austria in cooperation of the National Reference Centre for Influenza Epidemiology of the AGES (PD Dr. Daniela Schmid; DI Lukas Richter) with the National Reference Laboratory for Influenza at the Department of Virology of the Medical University of Vienna (Univ.-Prof. Dr. Theresia Popow-Kraupp; Dr. Monika Redlberger-Fritz).
Final analysis for the 2019/2020 season (as of 10.06.2020, evaluation until week 20/2020):
Table 1: Estimated number of deaths associated with seasonal influenza (IA) and temperature extremes (ET) including 95% confidence interval (CI) for the seasons 2015/2016-2019/2020 (each week 40-KW 20 of the following year), Austria.
|Season||CW||Number of estimated deaths (95% CI) associated with influenza (IA)||Number of estimated deaths (95% CI) associated with extreme temperature (ET)|
|2016/2017||40-20||4.436 (4.242; 4.634)||134 (90; 183)|
|2017/2018||40-20||2.851 (2.688; 3.016)||199 (144; 260)|
|2018/2019||40-20||1.373 (1.246; 1.504)||10 (-2; 37)|
|2019/2020||40-20||834 (723; 950)||-|