Screwworm Outbreak Spreads to 47 U.S. Cases as USDA Traps Catch 0 Wild Flies
Updated
Updated · The New York Times · Aug 27
Screwworm Outbreak Spreads to 47 U.S. Cases as USDA Traps Catch 0 Wild Flies
3 articles · Updated · The New York Times · Aug 27
Summary
Forty-seven U.S. screwworm cases have been confirmed since early June, but the Agriculture Department has not caught a single wild fly despite months of surveillance.
USDA has deployed more than 128 screwworm-specific traps and 8,000 exotic fruit fly traps, yet dashboard data show none has captured the insect needed to pinpoint the outbreak’s source.
The pest has now been found in cattle, sheep, goats and a handful of dogs across 18 counties in Texas and another state, raising the risk of wider livestock losses if infestations go untreated.
More than $1 billion is being spent on the response, including releases of sterile flies and aerial monitoring, after the parasite resurfaced in Texas for the first time in decades.
The stakes are high because screwworm once caused an estimated $200 million a year in losses for Texas ranchers before it was eradicated, and new detections in Mexico in 2024 had already put border defenses on alert.
With a billion dollars spent and zero wild flies caught, is the current eradication strategy failing against this flesh-eating pest?
As the US faces a massive sterile fly shortage, can next-gen tech stop this parasite before it devastates the cattle industry?
Why did a flesh-eating parasite eradicated decades ago suddenly bypass modern agricultural defenses to threaten America's livestock supply?
2026 Screwworm Crisis: 47 U.S. Cases, Economic Fallout, and the Race to Scale Up Sterile Fly Eradication
Overview
The August 2026 New World screwworm outbreak in Texas and New Mexico has challenged containment efforts, as confirmed animal cases continue despite surveillance traps often failing to detect wild flies. This paradox is explained by the flies’ preference for living hosts over traps, making animal inspections crucial. The USDA’s response—expanding surveillance, public vigilance, and releasing sterile flies—has slowed the northern spread, but a severe sterile fly shortage means eradication is not yet possible. Meanwhile, strict quarantines disrupt livestock movement and threaten local economies, while labor shortages make daily animal inspections difficult for ranchers.