The purpose of this study was to examine the impact of influenza
on
hospitalization in the
Netherlands. Two methods were applied to estimate this effect: (a) regression
analysis and (b)
comparison of hospitalization in epidemic years with non-epidemic years.
Hospital discharge
rates in 1984–93 have been considered. The study shows that, during
the period studied, on
average, almost 2700 people were hospitalized for influenza per annum,
and that influenza was
diagnosed as the main cause for hospitalization in only a fraction of these
hospitalizations
(326: 12%). From an economic perspective, these results imply that the
cost-effectiveness of
vaccination against influenza may be severely underestimated when looking
only at changes
achieved in the number of hospitalizations attributed to influenza.