I used to eat a lot of sushi, until about 10 years ago I made a pit stop in the bathroom at Outdoor Emporium, and after wiping pulled about 4 feet of tapeworm out of my bunghole. It was a horrifying experience, to say the least. Got a one-dose med, a big chewable table like Vit C wafer the next day that was supposed to dissove the critter, apparently it did, but that was the end of sushi for this cowboy. Have seen worms in Puget Sound chinook at time while cleaning the fish, but I don't think those are tapeworms.