European Journal of Epidemiology

, Volume 27, Issue 7, pp 567–575

Attributable deaths due to influenza: a comparative study of seasonal and pandemic influenza

  • Monika Redlberger-Fritz
  • Judith Helene Aberle
  • Therese Popow-Kraupp
  • Michael Kundi
INFECTIOUS DISEASES

Abstract

Influenza epidemics lead to an increase in hospitalizations and deaths. Up to now the overall impact of attributable deaths due to seasonal and pandemic influenza viruses in Austria has not been investigated in detail. Therefore we compared the number and age distribution of influenza associated deaths during ten influenza epidemic seasons to those observed during the pandemic influenza A(H1N1)2009 season. A Poisson model, relating age and daily deaths to week of influenza season using national mortality and viral surveillance data adjusted for the confounding effect of co-circulating Respiratory Syncytial Virus was used. We estimated an average of 316 influenza associated deaths per seasonal influenza epidemic (1999/2000–2008/2009) and 264 for the pandemic influenza season 2009/2010 in the area of Vienna, Austria. Comparing the mortality data for seasonal and pandemic influenza viruses in different age groups revealed a statistically significant increase in mortality for pandemic A(H1N1)2009 influenza virus in the age groups below 34 years of age and a significant decrease in mortality in those above 55 years. Our data adjusted for co-circulating RSV confirm the different mortality pattern of seasonal and pandemic influenza A(H1N1)2009 virus in different age groups.

Keywords

Influenza mortality Pandemic influenza A(H1N1)2009 Influenza attributable deaths Influenza in Austria 

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Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  • Monika Redlberger-Fritz
    • 1
  • Judith Helene Aberle
    • 1
  • Therese Popow-Kraupp
    • 1
  • Michael Kundi
    • 2
  1. 1.Department of VirologyMedical University ViennaViennaAustria
  2. 2.Institute of Environmental HealthMedical University ViennaViennaAustria

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