333. Worms in Fish and Cheese
46:43 Small worms are sometimes found in fish, in the brain, the liver, the intestines, the mouth and the gills. This is common in such fish as pike and herring. When this is common, one must check for them. Small insects can also be found on the outside of a fish, on or near the fins, in the mouth and behind the gills. One must also check these places and remove any such bugs.
46:44 Worms that are found in cheese are not halachically problematic so long as they have not come out completely and the diner is not repulsed by them.