USDA Releases Billion Sterile Flies to Combat Resurgent New World Screwworm Threat in U.S.
The United States, in collaboration with Mexico and Panama, has released approximately one billion sterile flies as part of an effort to combat the re-emergence of the New World screwworm. This parasitic fly, once considered eradicated in the U.S., Mexico, and most Central American countries, breached containment barriers in the Darién Gap in 2023 and has been moving northward. The New World screwworm lays its eggs on warm-blooded animals, including humans, with larvae burrowing into living tissue, causing infections and potentially death. The U.S. Department of Agriculture (USDA) confirmed the first U.S. cases in years in June, with fewer than 50 incidents recorded so far this year. The strategy involves mass-breeding the insects, sterilizing them with radiation, and then releasing them. Wild female screwworm flies mate only once; if they mate with a sterile male, no offspring are produced, gradually reducing the population. A billion-fly shipment was sent to Texas from facilities in Chiapas, Mexico, and ... 
