I started getting fruit flies in the kitchen when my sink sprayer malfunctioned and sprayed water all under my kitchen sink. They just seemed to multiply from there! Couldn't even leave a cup that someone used to have a drink of water out without them crawling all over it! But try this...Mix 2 cups water, 2 tablespoons sugar, 2 tablespoons white vinegar, and a couple drops of liquid dishsoap. Leave this mixture sitting out wherever the infestation is for as long as you need to.