Massachusetts is home to many fly species that are either biting pests or indoor pests. The most common fly species that bite humans in Massachusetts include stable flies, horse flies, greenhead flies and black flies. Biting flies remain outdoors and they are not associated with indoor pest problems. The fly species that are well known for infesting Massachusetts homes include house flies, fruit flies, blow flies, and cluster flies. Although indoor fly pests do not bite, their bodies are covered in numerous disease-causing microorganisms. These microorganisms contaminate every indoor surface and food source that flies make contact with, and species that are attracted to bodily secretions, like the face fly, may spread bacteria directly onto mucous membranes in the eye socket, nose or mouth. House flies are the most common indoor fly pests throughout the US, and just one adult house fly can carry more than one million bacteria on its body. The house fly is considered the most medically significant of all indoor fly pest species in the US, as house flies commonly carry bacteria that cause typhoid fever, cholera and dysentery.

Disease-causing bacteria are most concentrated on fly hairs, and house flies contaminate food by expelling bacteria-rich vomit onto every food source in which they make contact. House flies are constantly acquiring bacteria from their filthy breeding sites, which include a wide range of rotting organic matter sources. House flies prefer to breed within garbage, excrement, spilled animal feed and soil mixed with decaying organic matter. House flies that breed on animal excrement, compost piles and bundles of leaf-litter within residential yards can pose a nuisance, especially when they enter homes. Rotting food in garbage receptacles is the most common indoor house fly breeding site, and it is not uncommon for numerous larvae (maggots) to emerge from garbage within homes. Keeping garbage receptacles sealed, and promptly removing full garbage bags from homes will deny houseflies access to their favored indoor breeding site. Also, dirty dishes should be washed regularly and garbage disposals should remain free of food waste. For active infestations, removing all potential and current breeding sites often suffices to eliminate house flies from homes.

Have you ever struggled to control house flies within your home?