US Plans To Breed Millions Of Flies, Release Them From Planes: Here’s Why

Last Updated:July 12, 2025, 22:14 IST

The US stopped livestock imports from northern Mexico due to the screwworm fly threat. USDA Secretary Rollins announced border tightening and a $30M sterile fly program.

US Plans To Breed Millions Of Flies, Release Them From Planes. (Representative/Pexels)

The United States has temporarily halted livestock imports from Mexico’s northern states due to the growing threat of the New World screwworm fly, a deadly flesh-eating parasite that has spread further north than anticipated.

The US Department of Agriculture (USDA) said that the parasite poses a danger to the country’s cattle industry. Female screwworm flies lay eggs in open wounds of warm-blooded animals. Unlike most fly larvae, their maggots feed on live flesh, which can lead to severe injuries or death in livestock.

The USDA is concerned that if the New World screwworm fly reaches Texas, it could inflict significant economic damage, echoing the devastating impact it had decades ago. The fly was largely wiped out in the 1970s through a special program where sterile male flies were bred and released. When these sterile flies mated with females, they prevented their eggs from hatching, ultimately reducing the population, the Economic Times reported.

The pest had been contained in Panama for years until it was found in southern Mexico late last year. Most recently, a new infestation was found about 370 miles (595 kilometres) from the Texas border, much further north than previously recorded.

What Is The US Doing?

USDA Secretary Brooke Rollins on Wednesday announced a border tightening measure to prevent the New World screwworm fly from entering the US. “Thanks to aggressive monitoring, we have been able to take quick and decisive action to respond to the spread of this deadly pest," Rollins stated, highlighting the proactive approach to containing the pest.

The US plans to invest nearly $30 million in building new facilities to breed and release sterile flies. This includes a new “fly factory" in southern Mexico, expected to launch by July 2026, and a holding site in southern Texas for rapid deployment of sterile flies from Panama if an outbreak occurs.

Mexican President Claudia Sheinbaum criticised the border closure, calling it “totally exaggerated." She emphasised that Mexico is implementing necessary protocols and working diligently to contain the New World screwworm fly outbreak.

Mexican authorities said there were 392 infected animals as of this week, a drop of nearly 19% since June 24. They believe the issue is under control.

US lawmakers are pushing for faster action. Representatives Tony Gonzalez (Texas) and Kat Cammack (Florida) urged the Trump administration to expedite approval for anti-parasite treatments, citing restrictive labelling rules as a bottleneck in the response to the New World screwworm fly threat.

If the New World screwworm fly infestation worsens, the US plans to deploy millions of sterile flies via aerial release along the southern border, aiming to curb the parasite’s spread as part of a long-term control strategy.

Location :

United States of America (USA)

First Published:

News world US Plans To Breed Millions Of Flies, Release Them From Planes: Here’s Why