急問：魚片中發現寄生蟲Urgent: found parasite in cod fish!

We went grocery shopping this morning and bought a piece of cod fillet as usual from Wegmans, a chained grocery store. When we started to cook it at noon, we found that there were parasite (like tiny earthworms) in the fillet! We bought cod fillet from them time to time and this really scares me. What should we do? Call the local office of New York State Department of Agriculture and Markets? I do not want to just return it to the store because we do not want this to happen again and we do not want it to happen to anyone else.