I've found it to be true

Living in Alaska, you have the opportunity to eat lots of fish. Halibut is a so-called bottom feeding fish and probably the most widely eaten fish here after cod and salmon. It does indeed sometimes have worms, and a friend who fishes tells me that certain areas in local waters are more apt to yield fish with parasites than others. I buy fish from a friendly guy who will readily tell me if the fish has worms, even when they're so small I can't see them-so maybe the answer is learn to identify them. I'm still eating fish!