The US is spending $8.5 mn to breed flies in Texas near Mexico border. Reason: 'man-eater' screwworms

The United States is building a fly-breeding facility in Texas at a cost of $8.5 million to combat the growing threat of New World screwworms—flesh-eating parasites that endanger livestock, pets, wildlife, and even humans. Agriculture Secretary Brooke Rollins announced the plan Wednesday, highlighting the urgency of preventing the pest's northward spread from southern Mexico.

The new sterile insect dispersal center at Moore Air Base is less than 20 miles from the U.S.-Mexico border. The facility will breed millions of sterile male screwworm flies (Cochliomyia hominivorax), which will be released into the wild to disrupt the pest’s reproductive cycle. When sterile males mate with wild females, no viable offspring are produced, gradually eradicating the population.

The U.S. Department of Agriculture (USDA) hopes to eventually release up to 300 million sterile flies weekly. A similar technique helped eradicate the screwworm in the U.S. by the 1960s, when a previous facility operated from the same Texas base.


Expanding Cross-Border Efforts
The USDA is also investing $21 million to convert a fruit fly facility near Mexico’s border with Guatemala into a screwworm fly-breeding center. This second plant, expected to be operational in 18 months, would join an existing facility in Panama that currently produces around 100 million sterile flies per week.

Mexico has welcomed the initiative. Mexican Agriculture Secretary Julio Berdegué praised the plan as a positive step and expressed optimism that cattle exports to the U.S.—recently suspended—could resume soon based on USDA inspection results.

Whare are scareworms
Screwworm infestations have recently been detected as close as 700 miles from the U.S. border. The parasite’s larvae burrow into wounds, feeding on living flesh and causing severe damage or death. While rare in humans, the pest affects all mammals, including pets and wildlife, and poses a multimillion-dollar risk to cattle ranchers if not controlled.

According to a report of CBS News, officials have voiced concern over wildlife migration as a possible vector, with feral pigs, deer, and other animals potentially carrying the parasite across the border unnoticed.

"We’ve defeated the screwworm before, and we will do it again," Rollins said, emphasizing the importance of rapid response and cooperation between U.S. and Mexican authorities.