This is an interesting tidbit also
http://www.iayork.com/MysteryRays/2013/03/25/2892/
An increased mortality from all or most of the causes that have been mentioned characterises all influenza epidemics, and not that of 1892 alone. It is impossible to believe that the invariable coincidence between the rise of these various causes of death and influenza is accidental, and the conclusion seems inevitable that influenza itself is the determining cause, though it does not so appear in the returns furnished to the Registrar-General. This being the case, in estimating the mortality of any particular epidemic it is necessary to allow for the deaths returned under other heads than that of influenza.
Citing –On the Influenza Epidemic of 1892 in London :: BMJ 2:353-356 (1892)