USDA Opens Sterile Fly Dispersal Facility in Texas

EDINBURG, Texas — The U.S. Department of Agriculture (USDA) celebrated the completion of a U.S.-based sterile fly dispersal facility in Edinburg, Texas, at Moore Air Base on Feb. 9. The facility, created to aid the agency’s fight against New World screwworm (NWS), expands USDA’s ability to disperse sterile flies along the border and into the United States, if necessary.

NWS, a parasitic fly whose larvae feed on the living flesh of warm-blooded animals, could pose a threat to U.S. livestock, wildlife and domestic animals, especially those involved in U.S. food systems like beef and dairy cattle, as the pest’s spread in Mexico inches closer to the U.S. border.

Sterile insect technique, when paired with surveillance, animal movement restrictions and education and outreach, is a proven and effective tool for controlling and eradicating NWS, said USDA.

Female NWS flies only mate once in their lives. If they mate with a sterile male, they lay unfertilized eggs that don’t hatch. Releasing sterile flies just outside of affected areas helps ensure flies traveling to new areas will only encounter sterile mates and will not be able to reproduce, said the agency.

Sterile insects are dispersed through aerial dispersal or ground release. Aerial operations are preferred because they allow for dispersal at a steady rate through large areas, including those that are unreachable from the ground. Ground release is used to quickly deploy sterile insects outside of the dispersal facility range. Mass production and targeted dispersal of sterile flies remain critical components of an effective response, said USDA.

Last month, USDA announced a shift in its 100 million per week sterile fly dispersal efforts to reinforce coverage along the U.S.-Mexico border. While sterile flies for this effort will initially be dispersed from the Tampico, Mexico facility, USDA said it is prepared to quickly and strategically shift operations to the new Texas facility should there be a change in the location or new concentration of NWS cases in northern Mexico.

NWS has not been detected inside the U.S. The northernmost active case of NWS is about 200 miles from the border, according to USDA.

"The Trump administration continues to bring the full force of the federal government to fight New World screwworm,” said U.S. Secretary of Agriculture Brooke Rollins. “This sterile fly dispersal facility was a high-priority project, and our team delivered it in record time. This new facility is a monumental achievement for our domestic preparedness efforts, but we are also diligently working to stop the spread of screwworm in Mexico, conduct extensive trapping and surveillance along the border, increase U.S. response capacity and encourage innovative solutions. We will never stop fighting to protect American agriculture. USDA, through a whole-of-government approach, will continue to hold Mexico accountable to mitigating the spread of this dangerous pest."

“America is going to take care of ourselves, including dealing with the approach of screwworm as it gets closer to our border,” said Texas Governor Greg Abbott. “We put together the resources necessary for Texas to provide a Texas-size response to this. We thank Secretary Rollins and President Trump for stepping forward to provide the stop gap effort essential to protecting our ranchers and our wildlife.”

Building a Sterile Fly Network.

USDA currently produces sterile flies for dispersal at the COPEG facility in Panama.

The agency is also investing $21 million to support Mexico’s renovation of an existing fruit fly facility in Metapa, which will double NWS production capacity once complete. With ongoing support from technical experts in USDA’s Animal and Plant Health Inspection Service (APHIS), Mexico anticipates this sterile fly production to begin as soon as summer 2026.

To expand USDA’s domestic response capacity, the agency said it is also building a sterile fly production facility at Moore Air Base in Edinburg, Texas, with a targeted maximum capacity of 300 million sterile flies per week. The agency said it expects to break ground on that facility later this spring.

With existing and planned production facilities fully operational, USDA said it will have up to 500 million sterile flies per week in its arsenal to fight NWS. The international network of facilities will produce 100 million sterile flies per week at COPEG in Panama, 100 million at Metapa in Mexico and 300 million at Moore Air Base.

USDA Asks Americans to Stay Vigilant.

USDA is asking Americans to remain vigilant by checking livestock and pets for signs of NWS.

Look for draining or enlarging wounds and signs of discomfort. Also look for NWS larvae (maggots) and eggs in or around body openings, such as the nose, ears and genitalia or the navel of newborn animals.

If you suspect your animal is infested with NWS, immediately report it to your state animal health official or USDA area veterinarian in charge.

NWS maggots can infest livestock and other warm-blooded animals, including people. They most often enter an animal through an open wound and feed on the animal’s living flesh.

Learn more about NWS and USDA’s efforts at Screwworm.gov.