Full Breakdown
New World Screwworm Outbreak Threatens U.S. Livestock
6/18/2026, 2:00:50 AM
Outbreak Overview
The USDA’s Animal and Plant Health Inspection Service confirmed 12 cases of New World screwworm (NWS) in the United States as of June 17 2026—11 active and one inactive. Infections involve cattle, goats, sheep and a dog across Texas counties (Edwards, Tom Green, Gillespie, La Salle, Sutton, Zavala, Zavala) and Lea County, New Mexico. The parasite’s larvae burrow into open wounds, feeding on living tissue. USDA officials state the food supply remains safe because the fly does not infest meat or produce.
Historical Context
NWS was eradicated from the United States in the 1960s after a multi-decade sterile-fly program. The parasite persisted in Central America until a northward migration in 2023 placed it near the U.S.–Mexico border. Funding cuts to a USAID-sponsored monitoring program in 2025 have been cited as a factor in the current resurgence.
Timeline of Confirmed Cases
- June 3: First U.S. case detected in a calf near La Pryor, Texas.
- June 7–12: Additional cases reported in Edwards, Gillespie, La Salle, Zavala, Tom Green, Sutton counties (Texas) and a dog in Lea County, New Mexico (June 8).
- June 15: USDA releases 4 million sterile flies on the ground and 4 million in the air.
- June 16–17: Pennsylvania issues a quarantine order; Michigan, Florida, and several other states adopt movement restrictions.
Key Figures & Agencies
- Sid Miller, Texas Agriculture Commissioner – advocates the Screwworm Adult Suppression System (Swass).
- Greg Abbott, Texas Governor – secured federal funding for additional inspectors and declared a local disaster in Tom Green County.
- Brooke Rollins, U.S. Secretary of Agriculture – oversees sterile-fly releases and a $750 million facility slated for 2027.
- Russell Redding, Pennsylvania Agriculture Secretary – issued a state quarantine.
- Wilton Simpson, Florida Agriculture Commissioner – barred rescue animals from Texas and New Mexico.
Data & Statistics
- 12 confirmed animal cases (11 active).
- > 142 million sterile flies released since February 2026; 4 million ground and 4 million aerial releases reported on June 16.
- $750 million allocated for a Texas sterile-fly production plant; total federal investment exceeds $1 billion.
- USDA projects a 0.9 % decline in 2027 beef production and record-high beef prices, already up ~75 % since 2020.
Impact on Agriculture
The outbreak threatens Texas’s multibillion-dollar cattle sector, already operating at the lowest herd size in 75 years. Potential economic loss from a 1976-scale event is estimated at $1.8 billion. State-level movement restrictions risk disrupting interstate trade and export markets, as illustrated by Canada’s temporary ban on Texas cattle.
Official Statements & Responses
Federal agencies emphasize containment: USDA reports rapid sterile-fly deployment and border-surveillance partnerships with DHS and CBP. State officials have enacted quarantine zones, expanded inspector staffing, and launched free online training for certified screwworm inspectors.
Criticism & Opposition
Republican officials have blamed prior border policies for the northward spread, while Democratic voices cite 2025 cuts to the Department of Government Efficiency that eliminated a key monitoring program. Texas Agriculture Commissioner Miller has criticized USDA for allegedly ignoring his early warnings.
On-the-Ground Reports
Local authorities in San Angelo (Tom Green County) declared a disaster, set up a 12-mile quarantine, and began free inspector certification. New Mexico’s Livestock Board established a 12-mile quarantine around Eunice after a dog tested positive. Pennsylvania veterinarians have urged daily wound inspections for livestock and pets.
Conflicting Reports & Gaps
Some outlets cite “more than 10” cases, while others list exactly 12; a few reports mention only seven confirmed cases. The precise number of wildlife infections remains unknown, with USDA reporting a “handful” of suspect wildlife samples that tested negative.
Verbatim Quotes
- “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
- “We’re gonna battle this and beat this back, and our ranchers are gonna be the frontliners,” — Brooke Rollins, U.S. Secretary of Agriculture
- “Taking proactive steps now to strengthen biosecurity and limit unnecessary animal movements from affected areas will help protect our farms and communities.” — Russell Redding, Pennsylvania Agriculture Secretary
- “It added that despite the outbreak, the US food supply remains safe, as the screwworm does not infest meat, fruits, vegetables or other fruit products.” — USDA statement (June 16)
- “We will respond based on facts, not fear. But we will also continue to be the most aggressive state in the nation when it comes to protecting our livestock, pets, wildlife, people, and agricultural economy from this threat,” — Wilton Simpson, Florida Agriculture Commissioner
What’s Next
USDA plans to operationalize the Texas sterile-fly facility by late 2027 and to award 40 Grand-Challenge grants for novel detection tools. States continue to refine quarantine maps, and the Senate’s bipartisan letter urges accelerated federal action. Ongoing surveillance along the southern border and in wildlife populations will determine whether the outbreak can be contained before it expands further north.
