You can help minimize flies near your home by understanding their behavior and using sanitation and other measures, says an Extension entomologist. Houseflies aren't just annoying, they are a potential hazard, says Faith Oi, an entomologist with the Alabama Cooperative Extension System. Houseflies are suspected of transmitting human diseases, including typhoid fever, dysentery, cholera and tuberculosis. They feed on fecal matter, discharges from wounds and sores, and decaying matter such as spoiled eggs, fish and meat.
Houseflies spread disease organisms by regurgitating and excreting wherever they land.
The tiny specks on many surfaces visited by house flies are the excreted wastes. While house flies live only about two and a half weeks during the summer, they can survive up to three months at lower temperatures. Flies normally stay within a half to two miles of their point of origin, but may travel up to 20 miles to find food and egg-laying sites. A female fly deposits 100 to 150 eggs in decaying matter such as grass clippings, garbage or human and animal waste, Oi says. Depending on how warm it is, the eggs hatch into maggots between eight hours and two days.