Despite its name, New World Screwworm (Cochliomyia hominivorax) is not a worm, it is a fly, and one of the most serious biosecurity threats facing livestock producers across the Americas today.
The female fly seeks out living animals, depositing her eggs in open wounds, sores, or natural body openings. Within hours, those eggs hatch into larvae that burrow into living tissue, feeding as they go. Unlike many other parasitic flies, New World Screwworm maggots do not feed on dead or decaying matter, they require living flesh to survive, making small entry points into open wounds and turning them into large, infected lesions within days. This makes the damage destructive, aggressive, and without prompt treatment, fatal.
Experienced producers know their animals and if something is amiss, when they see it. But the honest reality of managing a herd across multiple paddocks is that consistent, close-range observation of every individual animal, every day, at the same time, is not always possible. If it were, it would involve the extreme labour costs and time, that makes this almost impossible for producers.