An international observational study to characterize adults who are hospitalized with complications of influenza A – pandemic H1N1 (H1N1v)

Project no.: HIV-NAT 123/FLU 003

Brief summary: The purpose of this observational study is to describe the characteristics and outcomes over a 60-day follow-up period of participants with influenza A — pandemic H1N1 (H1N1v) who are hospitalized with severe and/or complicated influenza A in geographically diverse locations. Specific objectives are to estimate the percentage of patients who die, to obtain information on risk factors for mortality, and to establish a central repository of specimens for use in virus characterization, including subtyping, antigenic and genetic analyses, identification of signature mutations associated with antiviral drug resistance, mutational evolution, and additional reassortment. This information will be used to guide policymakers and to design future studies.


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