[Estimation of age-related fatality of influenza in Vienna 1970--1976 (author's transl)].

Starting with the total number of deaths the figures of the annual basic mortality and the deaths in excess of the usual expectancy during winter are estimated; the latter are subdivided into a basic excess group and a top excess group. A similar grouping is done with influenza cases (figure 1). Table 1. shows the results of the winter seasons from 1970--71 to 1975--76. It is remarkable, that a season without excess cases of influenza as it was in 1973--74 is followed by a season with raised fatality rates (like a "catch-up-fatality"). Table 2 shows finally, that the top excess fatality in the age group 15--64 years is more than twice as high as the basic excess fatality. In elderly people the relation is inverse. It seems that the high basic excess fatality in the observed period in this age group is due to the high incidence of preexisting chronic diseases, fatally complicated by influenza.