title: Real-time estimation of the hospitalization fatality risk of influenza A(H1N1)pdm09 in Hong Kong.
abstract: During the early stage of an epidemic, timely and reliable estimation of the severity of infections are important for predicting the impact that the influenza viruses will have in the population. We obtained age-specific deaths and hospitalizations for patients with laboratory-confirmed H1N1pdm09 infections from June 2009 to December 2009 in Hong Kong. We retrospectively obtained the real-time estimates of the hospitalization fatality risk (HFR), using crude estimation or allowing for right-censoring for final status in some patients. Models accounting for right-censoring performed better than models without adjustments. The risk of deaths in hospitalized patients with confirmed H1N1pdm09 increased with age. Reliable estimates of the HFR could be obtained before the peak of the first wave of H1N1pdm09 in young and middle-aged adults but after the peak in the elderly. In the next influenza pandemic, timely estimation of the HFR will contribute to risk assessment and disease control.
authors.affiliation: School of Public Health,Li Ka Shing Faculty of Medicine,The University of Hong Kong,Hong Kong Special Administrative Region,China.
authors.forename: J Y
authors.initials: JY
authors.lastname: Wong
authors.affiliation: School of Public Health,Li Ka Shing Faculty of Medicine,The University of Hong Kong,Hong Kong Special Administrative Region,China.
authors.forename: P
authors.initials: P
authors.lastname: Wu
authors.affiliation: School of Public Health,Li Ka Shing Faculty of Medicine,The University of Hong Kong,Hong Kong Special Administrative Region,China.
authors.forename: E H Y
authors.initials: EH
authors.lastname: Lau
authors.affiliation: School of Public Health,Li Ka Shing Faculty of Medicine,The University of Hong Kong,Hong Kong Special Administrative Region,China.
authors.forename: T K
authors.initials: TK
authors.lastname: Tsang
authors.affiliation: School of Public Health,Li Ka Shing Faculty of Medicine,The University of Hong Kong,Hong Kong Special Administrative Region,China.
authors.forename: V J
authors.initials: VJ
authors.lastname: Fang
authors.affiliation: School of Public Health,Li Ka Shing Faculty of Medicine,The University of Hong Kong,Hong Kong Special Administrative Region,China.
authors.forename: L-M
authors.initials: LM
authors.lastname: Ho
authors.affiliation: School of Public Health,Li Ka Shing Faculty of Medicine,The University of Hong Kong,Hong Kong Special Administrative Region,China.
authors.forename: B J
authors.initials: BJ
authors.lastname: Cowling
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006723:Hong Kong / Q000453:epidemiology; D006760:Hospitalization; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000302:isolation & purification*; D007251:Influenza, Human / Q000453:epidemiology / Q000401:mortality* / Q000821:virology*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D018570:Risk Assessment; D016019:Survival Analysis; D055815:Young Adult
keywords: Epidemiology; influenza A