No worms! The worms are in a later greek text. KJV has them, most modern translations use the Westcott hort text, which is a compilation of the earlier text. Textus receptus is the manuscript used in the KJV, hence the worms.

The fire is not necessarily literal, but that doesn't mean it isn't bad. It tends to be fairly difficult to explain to people what eternity will be like, so metaphor can come in handy. And quicker.