Inside the Screwworm Fight: USDA Strategy Centers on Sterile Flies and Producer Vigilance

Dr. Stephanie Mercier, Senior Policy Adviser for the Farm Journal Foundation, discusses USDA’s New World Screwworm eradication, sterile fly production, trade restrictions, biosecurity, and the path ahead for U.S. cattle producers.

ALEXANDRIA, VA (RFD NEWS) — Efforts to contain and ultimately eradicate New World screwworm continue to intensify as expanded detections in Texas prompt a broader federal response and renewed coordination across the livestock industry.

Dr. Stephanie Mercier, Senior Policy Adviser at the Farm Journal Foundation, joined us on Thursday’s Market Day Report to discuss USDA efforts to eradicate the pest in the United States.

In her interview with RFD News, Dr. Mercier explained that sterile fly dispersal remains the primary and most effective tool currently being used to stop the spread of the livestock parasite. She also emphasized the importance of producer vigilance, noting that New World screwworm can affect a range of warm-blooded animals beyond cattle, including dogs, goats, and horses.

“I think the dispersal is the major tool in the toolbox right now,” she said. “The other one is that it’s important that cattle ranchers and other livestock owners are vigilant about checking their animals on a regular basis to make sure that there’s not an infestation of these New World screwworm larvae affecting their animals."We need to keep in mind it’s not just cattle that these flies are attacking. It’s really any warm-blooded animal. Two of the seven cases that have been detected were not cattle.”

Dr. Mercier also discussed other parts of USDA’s ongoing response strategy, including its “Grand Challenge” initiative, which gathered more than 200 private-sector proposals aimed at stopping the spread of the pest.

“I’ll be interested to see what comes out of this Grand Challenge,” Dr. Mercier told RFD News. “But my suspicion is a lot of what’s going to be funded through that is going to be a long-term effort, not a short-term response.”

She also reflected on recent trade and livestock movement restrictions imposed by several states and Canada in response to detections in Texas. Mercier described those actions as precautionary measures that are unlikely to significantly affect the spread of disease but could have economic impacts on affected producers.

“I think it’s an expected move,” Mercier explained. “It’s not necessarily going to have much effect because I don’t think a lot of Texas animals move across the border on a regular basis. I think it’s a precautionary move that probably won’t have a major impact on the spread of this pest, but it could have an impact on the profitability of Texas cattle operations.

Mercier also addressed concerns from livestock producers about reporting suspected cases, noting that some may worry about potential quarantines or movement restrictions.

“I can understand their concern that if they find what they think might be a case and report it, that could end up with their operations being quarantined and movement of their cattle restricted, which for some producers may be a disincentive for reporting it,” Dr. Mercier said. “I still think those two things I mentioned at the top—the dispersal of sterile flies and the monitoring by farmers—are the two most important things we’ll have to rely on for the next several months.”

She stressed that strong biosecurity depends on coordinated action across neighboring operations and that early reporting is essential to preventing further spread.

“We all need to work together on this,” she continued. “But it’s very important to keep in mind that good biosecurity measures depend not just on what you’re doing on your farm, but what your neighbors are doing as well. And if one farmer, or a handful of farmers, decides not to abide by their request, then that could allow this to go on even longer than it otherwise would.”

She explained that current sterile fly production capacity is significantly lower than the levels used during past eradication efforts, such as the 1960s outbreak response, thereby limiting the speed of containment. She warned that strict adherence to biosecurity at the operation level is absolutely critical at this stage. She also reiterated that if producers believe they come across the pest in their herds or other animals to report to local agriculture officials immediately.

“They need to report it — whether it’s to their veterinarian or to the local extension office or relevant state agencies in Texas or whatever state — let those authorities determine whether or not it’s an actual case,” she cautioned. “Farmers should not rely on their own judgment. They should pass on the suspicion that a case may exist and let someone else confirm it.”

Looking ahead, Mercier said much of the innovation emerging from USDA’s Grand Challenge is likely to focus on longer-term solutions, while near-term control will continue to rely heavily on sterile fly dispersal and producer monitoring.

LEARN MORE: www.screwworm.gov

Related Stories
As fall weaning begins, Jake Charleston explains how Livestock Risk Protection can establish a price floor for calves while allowing producers to benefit if markets rise.
Secretary Rollins urged state partners to review their wolf management policies, strengthen engagement with livestock producers, and work with the U.S. Department of Agriculture (USDA) to address wolf predation.
Lower-cost grains are replacing corn in livestock feed as China’s hog sector weakens.
Willingness to pay for beef climbed in September despite continued pressure on household budgets.

Marion is a digital content manager for RFD News and FarmHER + RanchHER. She started working for Rural Media Group in May 2022, bringing a decade of digital experience in broadcast media and some cooking experience to the team.

LATEST STORIES BY THIS AUTHOR:

U.S. farm debt has topped $605 billion, but vendor financing and other nontraditional lending may mean USDA estimates do not capture the full amount owed.
Matt Frostic is bringing a farm-level perspective to E15, trade, the Farm Bill, and new corn markets as the new leader of the National Corn Growers Association.
RealAg Radio host Shaun Haney discusses the latest AEM equipment sales figures and the financial pressures affecting machinery purchases in the United States and Canada.
Lewis Williamson with HTS Commodities discusses fall harvest conditions, USDA’s October WASDE report, grain demand, and post-harvest storage.
Mitt Walker with the Alabama Farmers Federation joined RFD-TV to discuss the storm’s impact on Alabama agriculture, recovery efforts, and the additional financial pressure facing producers.
Brooks York with AgriSompo discussed hurricane-related crop insurance coverage and how the HIP-WI endorsement determines whether a claim is triggered.
Kyle and Natalie Blum, founders of Solar Shepherds, discussed how solar grazing works, its potential benefits for livestock producers, and the importance of keeping agriculture part of the changing rural landscape.
Saydee Longhurst’s story shows how farmers and advocates can connect consumers with agriculture, share farm life, and introduce young people to industry careers.
OOIDA’s Lewie Pugh says varying state rules and highway fuel-tax obligations could limit the benefits of Trump’s temporary red-dyed diesel order for truckers.
President Donald Trump says Russia will supply millions of tons of diesel fuel to global markets in a deal he expects to lower prices for farmers, ranchers, and truckers.
President Trump wants to strengthen enforcement of the Packers and Stockyards Act, but R.J. Layher says the Farm Bureau wants USDA to keep three rules in place.
USDA Under Secretary Dudley Hoskins discusses cattle port safeguards, screwworm surveillance, and plans to expand sterile fly production in Texas.
Agriculture Shows
Agriculture is the most important industry in the world, and Ag PhD Daily brings you the information you need to best manage your business only on RFD-TV and RFD+
Hosted by Scott “The Cow Guy” Shellady and RFD News Markets Specialist Tony St. James, Commodity Talk delivers expert insight into the day’s ag commodity markets just before the CME opens. Only on RFD-TV and Rural Radio SiriusXM Channel 147.
A look at the news, weather and commodities headlines that drove agriculture markets in the past week.