Not Spanish Flu, but from the Cholera outbreak in the mid 1800s in Germany. The German is already a bit bumpy compared to todays and I am not a translator, but I hope it gets the point across:

"The lower classes couldn't endure this situation and saw, believing the most absurd rumors, in the measures only their demise.

...because the agitated crowd were delusional, misguided by a few agitators, believing that the safety measure against the cholera were only used to "eradicate the common plebs"'
Chronicles of the City of Stettin, 1849, Page 919