Influenza Burden Assessment in the United States, July1997 - up to April 2009

"The study will use multiple primary data sources: the Nationwide Inpatient Sample (for hospitalisations) and the US National Vital Statistics System (for mortality), and weekly virology data from the Centers for Disease Control and Prevention (CDC) influenza surveillance program supplemented with literature data.~Weekly time series of the rates of various severe influenza-related health outcomes will be constructed. Statistical models, guided by weekly numbers of cases of laboratory-confirmed influenza and respiratory syncytial virus (RSV) contained in the CDC virology data, will be constructed to estimate the portions of the various outcomes that can be attributed to influenza. Next, the seasonal impact of influenza by age, risk status, and influenza subtype will be assessed. Finally, the potential burden that a quadrivalent vaccine could have prevented over the 12 year study period will be predicted."