How Pynchon once mistook a virus for a metaphor

[Kai Frederik Lorentzen]

The concrete sentence from "Entropy" goes like this:  "Not even the 
clean constant winds of Switzerland could cure the GRIPPE ESPAGNOLE: 
Stravinsky had had it, they all had had it". Oh well ...

https://en.wikipedia.org/wiki/Spanish_flu

" ... Though it may not be wrong absolutely to make up, as I still do, 
what I don't know or am too lazy to find out, phony data are more often 
than not deployed in places sensitive enough to make a difference, 
thereby losing what marginal charm they may have possessed outside of 
the story's context. Witness an example from 'Entropy.' In the character 
of Callisto I was trying for a sort of world-weary Middle-European 
effect, and put in the phrase GRIPPE ESPAGNOLE, which I had seen on some 
liner notes to a recording of Stravinsky's L'HISTOIRE DU SOLDAT. I must 
have thought this was some kind of of post-World War I spiritual malaise 
or something. Come to find out it means what it says, Spanish influenza, 
and the reference I lifted was really to the worldwide flu epidemic that 
followed the war.
    The lesson here, obvious but now and then overlooked, is just to 
corroborate one's data, in particular those acquired casually, such as 
through hearsay or off the backs of record albums ..."

Slow Learner (Introduction)