Flies are a nuisance to people around the world wherever livestock is kept or garbage accumulates. The common house fly, Musca domestica, is by far the most common fly in and around houses, in villages and in urban areas with insufficient sanitation. It, together with other filth flies, is of public health importance, because it transmits disease-causing organisms.

Flies breed in any decaying, rotting organic matter like garbage, filth, excreta, manure etc. Garbage dumps attracts flies for food and to lay eggs. Flies regurgitate when feeding; this habit, together with particles of refuse stuck to their bodies, leads to contamination of human food and transmission of disease.