Screw-worm females lay 250-500 eggs in the exposed flesh of warm-blooded animals, including humans, such as in wounds and the navels of newly-born animals. The larvae hatch and burrow into the surrounding tissue as they feed. If the wound is disturbed during this time the larvae burrow or "screw" deeper into the flesh, which is the source of the insect's name. The maggots are capable of causing severe tissue damage or even death to the host. Approximately three to seven days after hatching the larvae fall to the ground to pupate. The pupae reach the adult stage about seven days later. Female screw-worm flies mate four to five days after hatching. The entire life cycle is approximately twenty days. A female can lay up to 3,000 eggs and fly up to 200 km (125 miles) during her life.

Screwed