Earlier quoted context omitted.
> "the congress flu" (never heard anyone call it 'plague', either) I think the "Seuche" in Congress-Seuche falls somewhere in between. I can attest that at least Congress-Seuche has been in use in the past, somewhat analogous to the annual "Wiesnseuche" flu wave in Munich during and after the Oktoberfest.
Last time congress happened, I didn't speak German at all. I just meant the translation; that I've only ever heard it called flu (from what I remember). Things being lost in translation isn't new though, so of course I trust that the German word can mean that :)
The annual post congress malaise goes by many names. Conflu, CCCbola, Congress Plague, Congress Colds, "I didn't drink that much tschunk why do I feel shit a week later", etc ;)