screwworm Infestation Confirmed in Florida Livestock, Triggering Emergency Response
TALLAHASSEE, FL – Officials from the United States Department of Agriculture and the Florida Department of Agriculture have confirmed the presence of the New World screwworm in a small livestock herd in southern Florida. The parasite, a species of fly larvae known for infesting open wounds and causing severe tissue damage in warm-blooded animals, was identified after a rancher reported non-healing wounds on several cattle.
The discovery, made on Monday, prompted an immediate quarantine of the affected property and the activation of a state-federal emergency response plan. Agricultural authorities have begun deploying sterile screwworm flies from a USDA facility as a containment measure. This biological control method aims to disrupt the pest’s reproduction cycle by releasing sterilized male flies to outcompete wild males.
According to the USDA’s Animal and Plant Health Inspection Service, the screwworm has not been established in the United States since a costly eradication program successfully eliminated it in 1966. A re-emergence could pose a significant threat to the national livestock industry, causing potential billions of dollars in losses.
Why this matters: The infestation risk stems from the screwworm’s ability to reproduce rapidly. A single female fly can lay up to 300 eggs in an open wound, and larvae can burrow into flesh within hours. The current outbreak is believed to have originated from a stray animal crossing the border from South America, where the pest remains endemic. Officials are urging all livestock owners to inspect animals daily for signs of infestation and to report any suspicious wounds to state veterinary authorities.