I'd imagine that food-born illnesses are mostly attributed to unclean surfaces at various points in food logistics. From the farm that grows and distributes, say, lettuce to the cutting board and dinnerware used by chefs.

I'd imagine that most restaurants/food distributors employing pastry chefs have other people to do the cleaning. So the likelihood that one could point a proverbial finger at a pastry chef as the source of a food-born illness is probably extremely low.