Acetic acid (vinegar) has had a long history of being used to treat fish diseases, but the references in Nelson Herwig's book all date from 1912 to 1974, so pretty old school. the doses are all over the board, but many of them list something like 500ppm for an hour.
Personally, I would use household bleach (no perfumes, etc. just sodium hypochlorite at 5.25%) at a 1:10 ratio, soak for ten minutes and then rinse REALLY well, and then even give a final soak of the item in water with extra dechlor added.
Jay