You can get a variety of worms from raw fish, including tapeworms and other parasites. They are supposed to examine the fish on a lightbox as they prepare sushi. I sure wouldn’t eat raw fish, or raw anything. You just never know, and all it takes is one little hunk of bad meat to get sick enough to die, or have an ichy anus, or worse, a hungry 20 foot tape worm. (it will keep you thin though)
Same thing happens with all foods, not just sushi.
The only sure protection against all germs, all pathogens, all bacteria is to live like Howard Hughes.