An accidental discovery of mine, this groan-worthy riddle is answerable with a single character when posted in a Slack channel:
What governs the level of disease?
As this is my first riddle here I'm wary of making it too obscure, so here are a few hints:
The wordplay here might make you seasick.
Actually, only the person who posts the riddle can supply the one-character answer!
If this is too all too backwards, let me know and I'll edit it.
Hint 4 (the clincher?) :
Since Deusovi is so close I'll add that the character you're looking for shows up on no keyboard. In fact it's invisible. The final result requires no creative reading, although is, as PuzzledPig notes, best read aloud.