There are many different types of fruit worms (larvae) that fall into the broad fruit worm category, including apple maggots, cherry fruit worms, etc.
The signs of fruit worms are often, malformed, shrunken, or shriveled fruit. Often, the fruit is rotten and pulpy and holes appear in the fruit.
It is impossible to control the worms during the current season's fruit, but they can be prevented or reduced over the year. In the spring, place Apple Maggot Traps out to capture the mature flies. The apple maggot trap and lure will attract and control many types of flies. The traps should be placed out early in the spring, about mid-April, as the flies lay their eggs in the new fruit, during the late spring and early summer period.
Also as soon as the flies appear, spray the area with Bug Buster Pyrethrin Insect Spray or Garden Insect Spray with Spinosad. Repeat the process every seven days, or so. You can also reduce the spread of apple maggot larva by collecting and removing any fruit that falls to the ground.