I got influenza and started throwing up. Is it the sickness doing that?
The tooltip seems to indicate the correct symptoms (with “fatigue, pain, thirst” as constant factors), so maybe just remove the nauseous effect if it’s there, or maybe it was something else that was causing the vomiting.
Oh, and on that note, how are you even getting influenza (or even the common cold for that matter) in the first place, with no living person to spread it to you? 