A few flies that enter through an open door or tear in a screen are a nuisance. But if they remain long enough to lay eggs, the nuisance quickly develops into a disgusting infestation. Finding fly larvae, known as maggots, in your garbage can is an unpleasant experience that can be avoided if you get rid of a fly infestation, no matter what its size, as soon as it's discovered.
Clean kitchen, bathroom and other surfaces with all-purpose cleaner mixed with water in a bucket. Sponge the areas to remove food and beverage residue that attracts flies. Pour 2 cups of the all-purpose cleaner down the kitchen drain to wash away grease and food particles that draw flies into the drain.
Throw away overly ripe fruits and vegetables on the countertop. Discard empty soda cans or food containers from around the house. Place garbage in a lidded container so flies can't lay eggs in the garbage.
Make a non-toxic fly trap to catch flies without harming children or pets. Pour 1 or 2 inches of cider vinegar into the bottom of a glass jar. Wrap plastic wrap over the top of the jar and secure it with a rubber band. Poke a few holes in the plastic wrap so flies can get in to the jar. Once the flies are lured in by the smell of the vinegar, they can't get out. Flush the flies and vinegar down the drain.
Catch flies with sticky fly paper hung in areas where they are prevalent. Keep a fly swatter handy to kill flies as you see them.