A similar first order cyclical regression model is used by the Centers for Disease Control to monitor pneumonia and influenza related mortality data [ 24], also with success.
We used weekly pneumonia and influenza (P&I) mortality data from the National Vital Statistics System (NVSS) (1972-1988) and the Centers for Disease Control and Prevention CDCC) 121 Cities Mortality Reporting System (1996-2008) to construct weekly time series of P&I mortality for each year and Census Bureau Division.
For illustration, we make use of the Pneumonia and Influenza (P&I) mortality data and vaccination data of the very young (age 0-2) and the very old (age >64) during 2004-2005 Taiwinternter influenza season to fit our model and to compute the relevant reproduction numbers.
Further suitable data sets - such as sentinel data of other influenza seasons or mortality data - should be identified for challenging the proposed influenza model for gaining more certainty that the presented model captures influenza dynamics reasonably well.
Estimation of the transmissibility of the 1951 virus using a mathematical model for influenza transmission fitted to mortality data (26 ) might answer this question, not only in Liverpool but also in the rest of England and Canada.
Influenza related hospitalisations and mortality data are also very scanty, and estimating the burden of disease as the excess of all-cause hospitalisations and deaths may have led to an overestimation, whereas using Eurostat case-specific events may have led to an underestimation of the burden, because very few influenza deaths and hospitalisations are recorded as such.
3 This method involved estimating a seasonal baseline for weekly mortality (all-cause or pneumonia and influenza) by fitting a sinusoidal function to the mortality data for periods when influenza was not active and then extrapolating to periods of influenza activity and attributing the excess to influenza.
Traditionally, epidemiological studies of influenza incidence have relied on excess mortality data, such as the U.S. pneumonia and influenza death rates maintained by the Centers for Disease Control and Prevention CDCC) in Atlanta, because these data sets generally contained information on the best available spatial and temporal scales [1], [7], [12].
Confusingly, in the latest HPA weekly national influenza report, the paragraph on mortality data seems to imply that the 50 deaths represent those across the UK... and yet the Department of Health has just confirmed to me that this number is deaths for England only.
