They are among the filthiest of insect pests. Habits and Damage Houseflies breed in decaying organic matter and feed indis-criminately on pet manure, garbage and the food on our tables. They contaminate everything they touch, and spread many human diseases. How to Control Houseflies You may keep your home free of houseflies by practicing sanitation, using screens, and applying insecticides. If only a few flies are present, it is more effective to get rid of them by using a fly swat rather than an insecticide.
Houseflies breed in places where garbage or manure accumulates.
Clean up these places. Promptly dispose of the droppings of pets. Do not allow food to stand where it will attract flies. Keep houseflies out by placing screens tightly in your windows and doors. See that screened doors swing outward.