Lulu, isn't fruit and raw vege okay as long as its washed?! Surely the caterer washed the stuff first . . .
Once it's been cut, it's high risk. In this case they hadn't washed the outside of the fruit before cutting (it doesn't mean it didn't look clean), the fruit salad was packed in takeaway containers and was there for 3 days before serving. All wrong - and yes the caterer is under strict regulation.