Flesh flies often prompt questions regarding their interactions with humans, particularly whether they bite. These insects, belonging to the Sarcophagidae family, are common across various environments globally. Understanding their natural behaviors and characteristics helps clarify their presence and potential impact on people.
Identifying Flesh Flies
Flesh flies are medium-sized insects, generally larger than common house flies (4-22 mm). They have a gray body with three black stripes on their thorax and a checkerboard pattern on their abdomen. Many species also have large, reddish eyes and a reddish-brown abdominal tip. These flies are common in urban and rural settings, often found near decaying organic matter like carrion, feces, or rotting vegetation, which serves as food and breeding sites.
Do Flesh Flies Bite?
Flesh flies do not bite humans; their mouthparts are designed for sponging liquids, not for piercing skin to draw blood like mosquitoes. Adult flesh flies primarily consume fluids from decaying animal matter, nectar, sweet substances, and animal waste. Human contact can occur, as flesh flies are attracted to strong odors, including those from open wounds or decaying food. Female flesh flies deposit live larvae, not eggs, directly onto suitable food sources like carrion or decaying organic material; in rare instances, larvae can be deposited on or near open wounds or mucous membranes, leading to a different type of interaction.
Potential Health Concerns
The primary health concern associated with flesh flies is myiasis, the infestation of living animal tissue by fly larvae. This occurs when female flesh flies deposit larvae on a host’s wounds, sores, or mucous membranes. While more common in livestock, myiasis can occur in humans, particularly in tropical regions or with neglected wounds; the larvae feed on the host’s tissue, which can lead to discomfort, irritation, and severe complications if untreated. Beyond myiasis, flesh flies can mechanically transmit harmful microorganisms by moving between unsanitary sites (carrion, feces, garbage) and human environments, potentially contaminating food and food preparation surfaces and leading to foodborne illnesses like diarrhea or dysentery.
Minimizing Contact
Reducing contact with flesh flies involves managing potential attractants and maintaining cleanliness. Promptly removing and disposing of dead animals (rodents, birds) is important, as these are significant breeding sites. Securing garbage in sealed containers with tight-fitting lids and regularly removing trash bags prevents flies from accessing organic waste. Maintaining good sanitation around the home, including cleaning up pet feces and other organic waste, helps eliminate breeding grounds. Installing and maintaining screens on windows and doors restricts entry into homes, and covering open wounds and sores also helps prevent accidental larval deposition.