All the produce you buy has little buggy eggs on them.
They're invisible. Even if you rinse your apples under the faucet, you're eating bug eggs by the mazillion. Maybe I should give you a nice little line break in which to pause and cope with this information.
Ok. Here's the proof - at the greenhouse where I work, Bill the owner insists on raising worms. They make compost. They live in a long box a lot like a coffin, they're probably playing pinochle in there. Bill feeds them table scraps, mostly fruit and vegetable left-over cut-off bits. I know his wife. I know how scrupulous she is about scrubbing all vegetables under fast water, even if they came from her own garden. Doesn't matter, eggs still there. The How To Grow Worms In a Box book says you should microwave all foodscraps, to sterilize, before feeding them to worms. But who wants to run plate after plate of watermelon rinds thru the microwave? a. time b. smell. So Bill just throws em in. The box seethes with fruit flies. Further reading of Worm Book reveals that said microwaving is specifically to kill said eggs. After being covered in a horrible tickly swarm more than once, I have convinced Bill that microwaving is worth the effort.
That said, there's no way for you to get rid of the ones you have. Impossible to squash and who wants to try to spray them all down. Stop having foody bits anywhere in the open, and starve em out. This includes sink/disposal, must be kept clean, or you'll be sorry.