Screwworm Fly Threat Prompts Federal Agriculture Response in Texas
A potential New World screwworm incursion along the southern border tests USDA's livestock disease containment infrastructure at a moment when cattle ranchers are already contending with...
The U.S. Department of Agriculture's Animal and Plant Health Inspection Service (APHIS) has issued active surveillance advisories for New World screwworm (Cochliomyia hominivorax) following confirmed detections in cattle near the U.S.-Mexico border corridor, according to APHIS public health notices dated May 2026. The screwworm, eradicated from the continental United States through a sterile insect technique program jointly administered by USDA and Mexican authorities since the 1960s, poses a direct threat to livestock by depositing larvae in open wounds of warm-blooded animals. USDA APHIS records the ongoing Sterile Insect Technique (SIT) program under cooperative agreement with Mexico's SENASICA agency as the primary containment mechanism.
Texas cattle producers operating near the Rio Grande Valley have reported heightened concern to the Texas and Southwestern Cattle Raisers Association (TSCRA), which has communicated directly with USDA APHIS field offices in the region, according to TSCRA public statements released in May 2026. The National Cattlemen's Beef Association (NCBA) submitted formal comments to USDA in April 2026 requesting increased SIT aircraft deployment and expanded border inspection protocols, filings available through USDA's public docket system.
The potential outbreak compounds existing economic pressure on Texas ranchers. USDA's National Agricultural Statistics Service (NASS) Cattle report published January 31, 2026 showed the U.S. beef cow herd at 28.2 million head, the lowest inventory recorded since 1961. Persistent drought conditions across Texas, Oklahoma, and the southern plains, documented in NOAA's U.S. Drought Monitor weekly releases through May 2026, have reduced available pasture and prompted producers to move cattle to market ahead of typical schedules, depressing per-head values.
Federal appropriations for USDA APHIS plant and animal safeguarding programs in fiscal year 2026 total approximately $1.03 billion, as reflected in the FY2026 Consolidated Appropriations Act signed into law. Of that figure, APHIS budget justification documents submitted to the House and Senate Agriculture Appropriations subcommittees identify the screwworm SIT program at approximately $35 million annually, a figure that has remained largely flat in inflation-adjusted terms since FY2022. No emergency supplemental appropriation specifically for screwworm response has been introduced in the 119th Congress as of June 6, 2026, per the congressional record.
What remains unknown is the precise number of confirmed screwworm cases in U.S. livestock as of this publication date. USDA APHIS maintains a foreign animal disease reporting portal, but case-level data for screwworm detections in domestic cattle is not publicly disaggregated in real time. Full case counts, geographic distribution, and the scope of any quarantine orders would be disclosed through APHIS Federal Order filings and the USDA Emergency Programs division, which are the public records that would clarify the current containment status.