Full Breakdown
New World Screwworm Outbreak Triggers Multi-Agency Response in Texas and New Mexico
6/17/2026, 12:34:46 AM
Outbreak Overview
The U.S. Department of Agriculture confirmed twelve New World screwworm (NWS) cases by mid-June 2026—eleven in Texas and one in New Mexico. The parasite, declared eradicated in the United States in 1966, re-appeared after moving north from Central America through Mexico in 2022. The first Texas case, a three-week-old calf in Zavala County, was identified on June 3, followed by infections in cattle, goats, sheep and a dog across Edwards, Gillespie, La Salle, Sutton, Tom Green and Zavala counties. TAHC responded by imposing movement restrictions in ten counties, later expanding quarantine zones to fifteen.
Response Measures & Official Statements
TAHC requires veterinary inspection and treatment certificates for livestock leaving infested zones. USDA’s APHIS deployed sterile-fly releases and the Screwworm Adult Suppression System (Swass) bait, while the FDA authorized emergency use of nitenpyram tablets for pets. Texas A&M’s Veterinary Emergency Team (VET) provides field inspections, treatments, and sample collection. The state launched a free online course to certify additional NWS inspectors. Officials describe a “multi-tool” approach that combines sterile-fly releases, quarantine enforcement, and expanded inspection capacity.
Criticism & Opposition
Republican leaders blamed border policies of the Biden administration for the pest’s entry, whereas Democratic officials cited funding cuts during the Trump administration as a contributing factor. Experts note that existing sterile-fly technology and surveillance mitigate immediate risk, suggesting political blame may distract from operational challenges.
Conflicting Reports & Gaps
Sources differ on the number of active cases—some list eleven, others twelve—and on the count of quarantine counties, reported as ten initially and later fifteen. The precise pathway by which NWS breached the sterile-fly barrier in the Darien Gap remains unknown.
Verbatim Quotes
- “The Texas A&M VET is proud to help in this time of challenge for our state,” — Dr. Deb Zoran, VET Director
- “The State of Texas will use every tool to protect our cattle industry and wildlife while we eradicate this pest,” — Gov. Greg Abbott, Governor of Texas
- “This should set off alarm bells across the country. Every day we delay gives this pest another opportunity to spread.” — Sid Miller, Texas Agriculture Commissioner
- “An infested animal is not a death sentence,” — Becky Trout Fryxell, Professor of Medical and Veterinary Entomology, University of Tennessee
What’s Next
TAHC will continue expanding certified inspector numbers, maintain sterile-fly releases through 2027, and monitor wildlife reservoirs. Ongoing outreach through AgriLife Extension and the online inspector course aims to sustain early detection. Federal agencies plan additional sterile-fly production facilities, with a new Texas plant slated for late 2027.
