TY - JOUR
T1 - Detection of excess influenza severity
T2 - Associating respiratory hospitalization and mortality data with reports of influenza-like illness by primary care physicians
AU - Van Den Wijngaard, Cees C.
AU - Van Asten, Liselotte
AU - Meijer, Adam
AU - Van Pelt, Wilfrid
AU - Nagelkerke, Nico J.D.
AU - Donker, Ge A.
AU - Van Der Sande, Marianne A.B.
AU - Koopmans, Marion P.G.
PY - 2010/11/1
Y1 - 2010/11/1
N2 - Objectives. We explored whether excesses in influenza severity can be detected by combining respiratory syndromic hospital and mortality data with data on influenza-like illness (ILI) cases obtained from general practitioners. Methods. To identify excesses in the severity of influenza infections in thepopulation of the Netherlands between 1999 and 2005, we looked for increases in influenza-associated hospitalizations and mortality that were disproportionate to the number of ILI cases reported by general practitioners. We used generalized estimating equation regression models to associate syndromic hospital and mortality data with ILI surveillance data obtained fromgeneral practitioners. Virus isolation and antigenic characterization data were used to interpret the results. Results. Disproportionate increases in hospitalizations and mortality (relative to ILI cases reported by general practitioners) were identified in 2003/04 during the A/Fujian/411/02(H3N2) drift variant epidemic. Conclusions. Combined surveillance of respiratory hospitalizations and mortality and ILI data obtained from general practitioners can capture increases in severe influenza-associated illness that are disproportionate to influenza incidence rates. Therefore, this novel approach should complement traditional seasonal and pandemic influenza surveillance in efforts to detect increases in influenza case fatality rates and percentages of patients hospitalized.
AB - Objectives. We explored whether excesses in influenza severity can be detected by combining respiratory syndromic hospital and mortality data with data on influenza-like illness (ILI) cases obtained from general practitioners. Methods. To identify excesses in the severity of influenza infections in thepopulation of the Netherlands between 1999 and 2005, we looked for increases in influenza-associated hospitalizations and mortality that were disproportionate to the number of ILI cases reported by general practitioners. We used generalized estimating equation regression models to associate syndromic hospital and mortality data with ILI surveillance data obtained fromgeneral practitioners. Virus isolation and antigenic characterization data were used to interpret the results. Results. Disproportionate increases in hospitalizations and mortality (relative to ILI cases reported by general practitioners) were identified in 2003/04 during the A/Fujian/411/02(H3N2) drift variant epidemic. Conclusions. Combined surveillance of respiratory hospitalizations and mortality and ILI data obtained from general practitioners can capture increases in severe influenza-associated illness that are disproportionate to influenza incidence rates. Therefore, this novel approach should complement traditional seasonal and pandemic influenza surveillance in efforts to detect increases in influenza case fatality rates and percentages of patients hospitalized.
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U2 - 10.2105/AJPH.2009.168245
DO - 10.2105/AJPH.2009.168245
M3 - Article
C2 - 20864730
AN - SCOPUS:77958163975
SN - 0090-0036
VL - 100
SP - 2248
EP - 2254
JO - American Journal of Public Health
JF - American Journal of Public Health
IS - 11
ER -