USDA’s Agricultural Research Service (ARS) is advancing the next evolution of the long-trusted sterile insect technique (SIT) to protect U.S. livestock from New World screwworm (NWS) by introducing a 100% male-only sterile fly strain. This breakthrough will effectively double the production capacity of sterile fly facilities without expanding physical infrastructure. By eliminating the production of “useless” female flies, the USDA-ARS innovation aims to push the NWS fly further south, providing a more robust and cost-effective defense for American livestock producers.
A USDA spokesperson explains, “USDA is using gold standard, proven scientific methods to manufacture NWS flies to produce only male flies and increase the efficiency of SIT. USDA is simply making a proven tool even more efficient and effective to better protect America’s farmers and ranchers.”
USDA currently produces sterile flies for dispersal at the COPEG facility in Panama. USDA 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.
Moore Air Base: On Time and On Budget for 2026 Production
Dudley Hoskins, USDA under secretary for marketing and regulatory programs, was a guest Tuesday on AgriTalk. He discussed sterile fly dispersal efforts.
“We’re doing two things,” he says. “One, the Secretary has us modernizing our infrastructure and our production capacity. She has us working on Moore Air Base, which will be a sterile fly production facility, that when it’s finally complete and at max-capacity production, will be producing about 300 million sterile flies per week. ”
Deputy Secretary Stephen Vaden recently reported USDA is on track and on time with regard to the Moore Air Base facility near Edinburg, Texas.
The Science of Stopping the Spread: Why Male-Only Matters
SIT, when paired with surveillance, movement restrictions and education and outreach, is an effective tool for controlling and eradicating NWS. Female NWS flies only mate once in their lives, so 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.
Hoskins says concurrent to the process at Moore Air Base, USDA is working with its partners at the ARS and Environmental Protection Agency (EPA) to evaluate the genetically-engineered fly — the NovoFly — which would help get more male flies in the sterile fly production facility.
Vaden calls the possibility exciting.
“Basically we’ve been losing half of the production at every facility because what we need are sterile male flies, but of course with nature, half of what you get are female flies, and those to this particular enterprise are useless,” he explains. “Thanks to our agricultural research service, we now have the ability to pump out 100% sterile male flies only, no wastage. That has the effect of doubling production without any change in the available facilities.“
He adds, “We expect to be able, once EPA approves that innovation is safe later this year, to have all those facilities, including the one under construction at Moore Air Base, pumping out 100% sterile male flies, which will make our ability to push this pest back further south where it belongs to take root and begin to have great effect. Not just to hold it, but to push it further south.”
Hoskins summarizes, “All of those things are in motion, all things happening concurrently, and all those will be critical in modernizing our toolbox to take the fight to the screwworm.”
Listen to the conversation on AgriTalk:
Regulatory Road Map: The EPA Public Comment Period
USDA is following established regulatory pathways and submitted to EPA an Emergency Use Exemption and Application for Registration. EPA published the notice of receipt and request for comments in the Federal Register on March 27 and is accepting public comments until April 27 before making a determination.
According to the notice, the application from USDA states: “To register a new pesticide product containing an unregistered pesticide, NovoFly male-only genetically engineered (GE) New World screwworm (NWS) in USDA’s Sterile Insect Technique (SIT) programs. Additionally, the Agency received a Section 18 quarantine emergency exemption application requesting use of the same pesticide to maintain broad suppression of and help prevent the pest from moving further northward from Mexico toward the United States.”
EPA is providing the notice in accordance with the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA).
The notice says, “Due to the urgent nature of the emergency, the limited time available to authorize the Section 18 quarantine emergency exemption request and the related FIFRA Section 3 product registration application under review for the same use, EPA is waiving the comment period associated with the emergency exemption request but is soliciting public comment in conjunction with the application for Section 3 product registration of NovoFly.”
To make comments or learn more, visit the EPA website.
Read more about sterile flies and current distribution:
