A flesh‑eating parasite just crossed our southern border into Texas cattle, and how we respond now will decide if ranchers face a controllable flare‑up or a full‑blown crisis.
Story Snapshot
- New World screwworm, a flesh‑eating fly, has been confirmed in a Texas calf near the border.
- Federal and state officials are relying mainly on sterile fly releases plus quarantines and surveillance.
- Texas leaders are pushing Washington to use every tool available to protect ranchers and wildlife.
- Experts say food in stores is safe, but livestock losses could be severe if the pest spreads.
What This Flesh‑Eating Screwworm Is And Why It Matters
New World screwworm is a parasitic fly that lays its eggs in the living tissue of warm‑blooded animals, usually inside fresh wounds.[2] The maggots hatch and eat living flesh, causing deep, painful holes that can spread fast and kill an animal if no one treats it.[2] Texas A&M experts note this pest was wiped out in the United States in the 1960s, so most producers have never seen it, even though it has stayed active in parts of Central America and Mexico.[2][5]
On June 3, 2026, the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service confirmed New World screwworm in a three‑week‑old calf in Zavala County, Texas, near the United States–Mexico border.[1][5] Inspectors found larvae in the calf’s navel area, a common target because the tissue is soft and exposed.[1] Federal officials say the U.S. food supply remains safe, since screwworms attack live tissue and do not infest meat in the grocery store.[1]
How Washington And Texas Are Responding On The Ground
Federal officials say they activated their New World screwworm playbook right away, building a unified command team with the Texas Animal Health Commission and sending staff into the area.[1][5] They set up a twenty‑kilometer infested zone around the ranch, with quarantines, movement controls, and intense surveillance of livestock and wildlife inside that circle.[1] They also increased trapping for flies along the border and just outside the usual sterile‑fly dispersal zone to catch any early spread.[1][6]
The heart of the federal strategy is the “sterile insect technique,” where planes and ground devices release huge numbers of sterile male flies.[2][5][6] When these males mate with wild females, no viable offspring are produced, and the population drops over time.[2] According to the U.S. Department of Agriculture, about four million sterile flies are already dropped from the air over the region each week, and new ground release chambers were rushed into the Texas hot zone.[1][6]
Debate Over Whether The Current Strategy Goes Far Enough
Texas officials and many ranchers welcome the sterile fly program but argue it should be just one part of a much tougher tool kit, not the main answer.[3] Texas Agriculture Commissioner Sid Miller warned that the first suspected case “demands use of all available tools,” and he called on President Trump’s administration to back a full‑court press that includes more aggressive field treatments and support for producers on the front line.[3] His message reflects deep concern that a slow start could allow the pest to dig in.
Animal‑health experts agree that on‑ranch action is critical, not optional. Texas A&M AgriLife and the Texas Animal Health Commission urge producers to inspect cattle daily, paying special attention to navels on calves, ears, branding and dehorning wounds, and any cuts or tick bites.[2][4] They advise ranchers to quickly clean and treat every wound, use approved topical larvicides like permethrin or coumaphos when screwworm is found, isolate suspect animals, and call their veterinarian and state officials before moving any stock off the place.[2][4]
Border Failure Fears, Human Risk, And What Comes Next
The screwworm’s return lands in the middle of long‑running anger about border security and disease control. The Centers for Disease Control and Prevention reports that since 2023, an outbreak in Central America and Mexico has caused more than 171,700 animal cases and nearly 2,000 human cases.[5] Federal agencies have been dropping about one hundred million sterile insects per week in Mexico and along the border to keep the pest from moving north, but new Texas cases show the barrier is under real stress.[5][6]
USDA confirms New World screwworm detected in 3-week-old calf in Zavala County, Texas, near US-Mexico border. A 20-km (12.4-mile) infested zone quarantine established & millions of sterile NWS flies will be released in Texas and Mexico in coming days. https://t.co/UWxqUc8CWV
— Reva Katz (@Reva4542) June 12, 2026
For families, experts stress that there is no sign of locally acquired human screwworm in the United States today, and the fly has not been found widely across the country.[5] The risk sits mainly with ranchers, wildlife, and pets in south Texas and nearby border areas, where any open wound can become a target.[2][4][5] Health and agriculture agencies urge people to keep cuts clean and covered, check animals often, and report any foul‑smelling, maggot‑filled wound right away so this threat can be crushed before it spreads deeper into America’s heartland.[2][4][5]
Sources:
[1] YouTube – Flesh-Eating Screwworm Found in Texas
[2] Web – New World Screwworm Resources
[3] Web – What to Do if You Suspect New World Screwworm in Your Herd
[4] Web – USDA Confirms New World Screwworm in Texas
[5] YouTube – New World Screwworm Found in Texas
[6] Web – Rethinking Livestock Management to Consider Screwworm
