How do you not get food poisoning by eating sushi if it is raw fish?

No sewage!: When you get food poisoning from raw seafood, it's usually from shellfish, such as oysters, that filter water that may be contaminated with sewage. That's not the case with fish used in sush, which swim around in the sea. However, you can sometimes get parasites, such as tapeworms, from sushi. As far as i'm concerned, it's worth the risk.