Maggot therapy. Medical staff applying a dressing containing live surgical maggots to a patient suffering from a leg ulcer. Larvae (maggots) of the greenbottle fly (Lucilia sericata) are able to clean wounds by eating dead, or dying flesh, and leaving healthy areas. The maggots prevent the growth of harmful bacteria in the wound by altering the acidity and releasing an antibiotic compound. This is a more efficient method for wound healing and prevention of gangrene or septicaemia than drugs or other treatments. Maggots are held in a cage-like dressing, or pouch, but allowed to move freely over the wound. A new dressing is applied every 2 days until the wound heals. Only this species of maggot, which is bred in sterile conditions, is used for surgery.