Texas committee hears plans for sterile‑fly production, bait and medicated feed as screw worm spreads in Mexico

A Texas legislative committee heard detailed briefings Tuesday on preparations for the New World screwworm after federal and state officials announced new response tools and funding.

“It's a threat to our $30,000,000,000 livestock industry here in our state,” Commissioner Sid Miller, Texas Department of Agriculture, told the Committee on Agriculture & Livestock as he described biosecurity steps, bait trials and requests for additional state support. Miller urged the legislature to allow a roughly $1 million biosecurity balance to roll forward so his team can buy traps, test kits and bait.

The hearing outlined three parallel approaches being advanced: (1) large‑scale sterile‑fly production, (2) chemical baits and traps to quickly reduce fly populations, and (3) expanded use of animal drugs — including feed‑through ivermectin/doramectin formulations in targeted zones — while surveillance and containment proceed.

Why it matters: Screwworm larvae feed on living tissue and can kill livestock and wildlife if infestations are not found and treated quickly. Witnesses said the pest is spreading in Mexico, has caused human infections there and has already disrupted markets; speakers warned that delays in building capacity or deploying treatments would raise the risk of an expensive and fast‑moving outbreak inside Texas.

Most important facts first

Dr. Louis Bud Dingus, executive director of the Texas Animal Health Commission (TAHC), said Mexican authorities and USDA announced major measures in recent weeks: USDA is supporting conversion of a facility in Matapa, Mexico with $21 million and Secretary Brooke Rollins announced a separate $750 million investment to build a sterile‑fly production and dispersal facility near Edinburg, Texas. Dingus summarized Mexican case counts and surveillance: “As of August 9 ... there are 4,684 accumulated cases of new world screwworms” and “as of August 5, there are 35 human cases reported in Mexico.” He also said USDA and state partners currently have about 101 screwworm‑specific traps placed between Del Rio and Brownsville.

Dingus told lawmakers the USDA and APHIS are developing a national response playbook and that a Texas response team will meet Sept. 4 to coordinate state preparedness.

Federal tools and gaps

Witnesses described two federal developments they said change the calculus. First, Secretary Rollins and USDA announced the planned domestic sterile‑fly facility and additional research funding; federal and invited witnesses described expected production capacity in widely differing estimates depending on stage and public statements: Dingus said a conversion project in Mexico was estimated to produce “60 to a 100,000,000 sterile flies a week,” while officials at the USDA press event described larger potential weekly capacity as programs scale. Second, according to testimony, the Department of Health and Human Services issued a declaration that allows the Food and Drug Administration to authorize emergency use of animal drugs to treat screwworms. Miller said that declaration means “the FDA was gonna release any any veterinary medicine, that could be used to treat would now be an emergency use.”

Even with those federal steps, witnesses urged faster action and additional state authority. Commissioner Miller requested a committee letter to the Legislative Budget Board to allow an existing roughly $1 million biosecurity balance in his agency to roll forward beyond the fiscal cutoff so his staff can buy test kits and traps now. Miller also asked the committee to consider requesting peace‑officer status for biosecurity inspectors who operate roadside inspection stations, saying the state spends “upwards of a half a million dollars, reimbursing DPS for their time.”

Bait and insecticide debate

Miller described work on a time‑released attractant his agency calls “TDA Swarm Lures” and urged approval and deployment of an attractant bait he said could “kill 90% of the screw worm flies.” He acknowledged regulatory questions about the insecticide used in baits; in testimony he referred to concerns about a product he called “dichloro” and noted alternatives such as coumaphos are long‑established in livestock pest programs. He emphasized that some uses would be in Mexico where EPA jurisdiction does not apply and that coordination with Mexican authorities is required before cross‑border baiting.

Research, containment and genetics

Philip Kaufman, professor and department head at AgriLife Research, described research opportunities if a secure research facility is made available near production operations. He and other researchers said modern tools — remote sensing, genetic sequencing of the screwworm genome and gene‑drive concepts — could, in theory, reduce the pest's ability to find wounds or scale sterile‑insect production, but that working with live screwworms in the U.S. requires APHIS permissions and high‑containment facilities. Kaufman said the current constraint is access to live insects for research and containment standards, and he recommended research space be colocated but physically separated from production to avoid cross‑contamination.

Medicated feed and emergency use: readiness vs. regulation

Multiple industry and feed‑manufacturing witnesses urged preparation to use oral, feed‑through macrocyclic lactones (ivermectin/doramectin) in narrowly targeted emergency zones, pointing to the 2016–17 Florida Key deer response where doramectin and sterile flies were credited with helping suppress an outbreak. Charles Echo of Lisonbee Echo Feeds and Robert Braden of the Texas Grain and Feed Association said manufacturers can produce a stable premix and run controlled, limited production when federal authorizations and product specifications exist. "We're not asking for mass use tomorrow or today," Braden said; he asked only that regulatory pathways and dosage testing be readied so the state can deploy feed options quickly if needed.

TAHC general counsel Janine Coggeshall told the committee that the commission currently “feels very stable where we are in our preparation for response” but echoed Miller by recommending lawmakers consider whether the emergency‑funding statute should be clarified so financial relief for producers could be available if animal disease is declared an emergency.

Surveillance, wildlife and front‑line reporting

Texas Parks and Wildlife and wildlife groups emphasized the importance of early detection by landowners, hunters, veterinary clinics and extension offices. Alan Kane, wildlife division director for Texas Parks and Wildlife, said the agency will use existing staff and local county biologists and build public messaging and signs in any designated infested zone. He described temporary authorizations that allow landowners or agents to take (dispatch) visibly infested wildlife for sampling and treatment under agency direction.

Dr. Dingus described an initial containment concept for a detected infestation: an immediate “infested zone” of about 12.2 miles where movement controls, increased inspection and surveillance traps would be imposed, followed by an adjacent surveillance ring. He said samples sent to National Veterinary Services Laboratories can often be identified “by noon” the day after collection, but stressed that rapid reporting by producers and citizens is crucial.

Industry concerns: movement protocols and markets

Livestock market and producer representatives urged clarity on permitted movement and quarantine protocols. Tim Nideken of the Livestock Marketing Association of Texas warned that overly broad control zones and unclear permitted‑movement rules could