The Dalai Lama said that “If you think you are too small to make a difference, try sleeping with a mosquito.” Insects in food facilities may be tiny, but they can make a big difference to your products. The housefly in particular may be relatively small, but it is certainly not harmless!
Between the feet, mouthparts, and hairs on the body, houseflies can pick up small particles of debris, food, and even dust. With that debris: pathogens. If you look closely at a housefly, you can see lots of hairs all over the body that particles can get stuck to. Looking at their feet and their mouthparts under magnification, you observe a large surface area. Ever heard that flies “taste” with their feet? Their feet have taste-sensing neurons to help them determine if something is food and if it is something they want to eat. While houseflies have a preference for sweets, they will feed on almost any number of liquid or semi-liquid food sources. The surfaces on their mouthparts and feet also pick up particles from the surfaces they land and feed on.