I have read somewhere that stomach flu does have symptoms which are to be considered as an illness itself.
Well I can approve this since nausea and diarrhea could be caused by other health issues. in my opinion you are happy if you have only one of those symptoms and you are damn cursed if you experience both at the same time.
Tip: Wash your hands before every meal, before every contact with food, and after every contact with possible infected person...otherwise you'll regret!
By for now, see you soon.