VICTORIA — Federal and state agriculture officials urged South Texas livestock producers on Wednesday, Aug. 19 to remain vigilant and quickly report suspicious wounds as the government expands sterile-fly production and surveillance to combat New World screwworm.
U.S. Rep. Michael Cloud hosted the panel discussion at Victoria College’s Emerging Technology Complex, bringing together officials from the U.S. Department of Agriculture, Texas Animal Health Commission and other agencies involved in the response.
The panel included Dudley Hoskins, under secretary, United States Department of Agriculture; Dan Hunter, state executive director, USDA; Stephen Diebel, president of Texas & Southwestern Cattle Raisers Association; Dr. Lewis “Bud” Dinges, state veterinarian of the Texas Animal Health Commission; Admiral Michael Schmoyer, associate administrator, USDA Animal and Plant Health Inspection Service; and Kory Gann, big game director of Texas Parks & Wildlife Department.
Hoskins said cooperation with ranchers and other livestock owners remains critical because New World screwworm can infest virtually any warm-blooded animal.
“The sharpest tool in our toolbox is partnership and vigilance and education and awareness,” Hoskins said. “When you all see something of concern, report it. We want to be a resource.”
New World screwworm larvae infest open wounds and feed on living tissue. Cattle are a primary concern, but horses, sheep, goats, hogs, pets and wildlife also are susceptible.
Sterile-fly production expanding
Hoskins said the United States has successfully eradicated screwworm before and now has more tools than it did during the campaigns of the 1950s and 1960s.
A key weapon remains the sterile insect technique, in which large numbers of sterilized male flies are released into affected areas. Females mate only once, meaning mating with a sterile male prevents production of offspring.
Hoskins said a Panama facility is producing about 100 million sterile flies per week. Another facility in Mexico is expected to begin producing roughly 100 million per week by late 2026 or early 2027.
USDA also is developing a production facility at Moore Air Base in Edinburg. Hoskins said the first phase is expected to reach production of about 100 million sterile flies per week by April 2027, with a second phase eventually adding another 200 million per week.
Combined, he said, production could reach roughly 500 million sterile flies per week — comparable to levels used during the earlier eradication effort.
Faster response to Texas cases
Schmoyer said improved modeling, faster diagnostics and surveillance have changed how officials respond.
Since June 3, 478 larval samples from Texas had been evaluated, with 45 confirmed as New World screwworm, according to Schmoyer. He said sterile flies have been deployed within 24 hours of every confirmed Texas case.
“We’re putting in the flies faster. We’re identifying the flies faster,” Schmoyer said.
He stressed that the parasite’s spread is often linked more to movement of infested animals than to the distance adult flies travel on their own.
“I can model what the environment is like. I can model the biology of the fly,” Schmoyer said. “Where I have difficulties is modeling human behavior.”
As of Wednesday, he said Mexico had 1,971 active cases and more than 38,000 total cases reported since November 2024. One recent case was detected about 18 miles from the Texas border in Chihuahua.
Schmoyer contrasted those numbers with Texas’ historic outbreak in 1972, when nearly 91,000 cases were reported statewide.
Wildlife surveillance increases
Officials also have increased wildlife surveillance. Schmoyer said more than 77,000 wildlife observations had been conducted in Texas since early June, including more than 25,000 using drones.
Twenty-nine animals had raised concerns, but no wild animal had tested positive for New World screwworm, according to Schmoyer.
More than 82,000 flies have been collected in Texas traps, he said, but none were confirmed as wild New World screwworm flies. Sterile screwworm flies released by the government have been found in the traps.
Texas establishes infested zones
Dinges said Texas had recorded 45 cases across 36 premises in 16 counties as of Aug. 19.
Approximately one-third of the cases involved the umbilical areas of newborn animals, while another third were associated with routine livestock practices that create wounds, such as castration, dehorning, branding or tail docking.
Dinges said the state has established 19 infested zones. A 12-mile-radius area is initially drawn around a confirmed case and then adjusted using roads, property boundaries and other landmarks.
Animals may still move out of an infested zone, Dinges said, but generally must be inspected, treated when required, identified and accompanied by proper documentation.
“We’re not here to impede commerce,” he said. “We’re committed to keeping commerce moving as best we can.”
The Texas Animal Health Commission has inspected nearly 47,000 animals in affected areas, Dinges said, including about 33,000 inspected for movement out of infested zones.
Producers urged to inspect animals
Dinges encouraged producers to regularly examine livestock, reduce unnecessary wounds, maintain working facilities and address cuts or injuries quickly.
He said ranchers should pay particularly close attention to newborn animals and animals undergoing management practices that cause wounds.
“Probably the best thing that you can put on your livestock are your eyes,” Dinges said.
He also encouraged livestock owners to establish relationships with veterinarians because some drugs available for prevention, treatment or control of screwworm require prescriptions or veterinary oversight.
Officials warn against misinformation
Cloud opened the discussion by saying government officials need continued input from those working directly in agriculture.
“I think the best policy is formed from the people doing the work as opposed to people 2,000 miles away who think they know everything,” Cloud said.
Officials repeatedly emphasized that reporting suspicious wounds remains one of the most important steps producers can take.
“This is not a problem that you can sweep under the rug,” Hoskins said. “If we’re not looking for it, fighting it and knocking it down, it’s going to get worse, not better.”
