I'm more concerned with what happens outside the grill.........
A lot of it is common sense stuff.....wash hands often, don't use same utensils for both raw & cooked, clear prep areas with some type of disinfectant, etc.
Weak chlorine bleach solution (like 6~7%) is a good idea for cutting boards, as even soap may miss something sometime.........
I'll wash my hands quite a bit or if it's in a difficult situation to do so, at very least use clean water & a dry, clean towel........
Only time I remember anybody getting "growly stomach" or anything was in the early 90's & it turned out my buddy wasn't rinsing the dishes well enough.....soap will work well as a digestive aid.....a little too well, in fact.........
If you have a healthy concern about on cooker grates & accessories, maybe do what the big boys do.....
The people who run large offsets & the like will use a weed burner quite often, then scrape down good, maybe another quick torching & oil up................