Texas Gov. Greg Abbott announced Monday that the state has escalated its emergency response to a Level II after federal officials confirmed multiple cases of the New World screwworm, a parasitic fly larva that burrows into the flesh of living animals, in South Texas and southeastern New Mexico.
The Texas State Emergency Operations Center is now running under what Abbott called a Level II Escalated Response, a designation that unlocks additional state resources to fight the parasite before it can spread through the state's massive livestock industry.
The first confirmed case surfaced on June 3 in a three-week-old calf in Zavala County, deep in South Texas ranch country. Three more cases followed quickly, additional calves in Zavala and La Salle counties, and a dog across the state line in New Mexico's Lea County. By June 5, officials with Texas A&M AgriLife Extension were working inside the State Operations Center in Austin. By June 6, the Texas Animal Health Commission had set up livestock checkpoints along U.S. Route 83 near La Pryor, stopping travelers leaving Zavala County and warning them about the outbreak.
That speed matters. The New World screwworm was eradicated from the United States in 1966 after a decades-long federal campaign. It came back once, a small outbreak in the Florida Keys in 2017, which officials stamped out. Now it has returned again, this time along the southern border, in a region where cattle, goats, and deer are economic lifeblood.
The USDA has said the New World screwworm poses a major threat to livestock. The fly lays eggs in open wounds on living animals. Larvae hatch and burrow into flesh, feeding on tissue and often causing what federal officials describe as "serious and deadly damage." The parasite primarily targets livestock but can also infect birds and humans.
The fly is endemic to parts of the Caribbean and South America. Its reappearance on U.S. soil, particularly in border counties, raises immediate questions about how it arrived and how far it may have already spread.
The USDA is responding by releasing sterile flies near confirmed detection sites. The technique, which dates back to the original eradication campaign, floods the area with male flies incapable of reproduction, preventing females from mating successfully. It worked in 1966. It worked in the Florida Keys in 2017. Federal and state officials are betting it will work again.
Abbott, in a statement reported by FOX Weather, framed the threat in direct economic terms:
"The protection of our ranchers, livestock producers, deer breeders and the Texas economy from this pest is a top priority."
He followed with a message aimed at Texans on the ground:
"We have eradicated this pest before, and we will do it again in close cooperation with our federal partners. Texans should stay alert, check animals daily for wounds and report any suspected cases immediately."
The federal government has moved in parallel. President Donald Trump appointed John Bellinger, described as a Texas cattleman and food safety leader, as senior advisor for New World Screwworm Preparedness. The appointment was announced through the USDA's New World Screwworm Rapid Response effort.
Bellinger's appointment puts a working rancher, someone who understands the ground-level consequences of a screwworm outbreak, at the center of the federal response. That is a practical choice. The people most at risk from this parasite are not Washington bureaucrats. They are the men and women running cattle in Zavala County, hauling livestock through La Salle County, and checking their animals for wounds every morning before dawn.
The Texas Animal Health Commission is providing diagnostic services and community outreach, and officials are urging anyone who suspects a screwworm case in livestock to report it to the commission immediately. The USDA maintains a running list of confirmed screwworm cases reported in the past 30 days.
The New World screwworm is endemic to parts of the Caribbean and South America. It was wiped out in the continental United States nearly sixty years ago. It reappeared briefly in the Florida Keys, an entry point from the Caribbean, in 2017. Now it has turned up in South Texas border counties and just across the line in New Mexico.
The obvious question is how the parasite got here. The USDA has not publicly detailed a pathway. But the geography speaks plainly. Zavala County sits roughly 100 miles from the Mexican border. La Salle County is even closer. Lea County, New Mexico, borders Texas and sits in a corridor of cross-border livestock and wildlife movement.
For years, border security debates have focused, rightly, on illegal immigration, drug trafficking, and cartel violence. But porous borders carry biological risks, too. Livestock diseases, invasive species, and parasites do not respect immigration law. They cross wherever the barrier is weakest.
The screwworm's return is a reminder that border security is not just a law enforcement issue. It is an agricultural security issue. It is an economic security issue. Texas ranchers already operate on thin margins. A full-blown screwworm infestation, the kind that plagued American livestock before the 1966 eradication, could devastate herds and drive costs through the industry.
Texas has a pattern of acting before the federal government finishes deliberating. Abbott's decision to activate the State Emergency Operations Center and deploy additional resources follows that pattern. The Level II Escalated Response was declared the same day the USDA confirmed additional cases. Livestock checkpoints were operational on U.S. Route 83 by June 6.
That kind of speed is not accidental. It reflects a state government that has learned, through border crises, hurricanes, and grid failures, that waiting for Washington to move first is a losing strategy.
The coordination between Austin and the federal government appears to be working, at least for now. The USDA is deploying sterile flies. The Texas Animal Health Commission is running diagnostics and outreach. Trump has put a cattleman in charge of federal preparedness. Abbott has activated emergency operations.
But the real test is containment. Four confirmed cases across three counties in two states suggest the screwworm has already established a foothold. The sterile-fly technique is proven, but it requires speed and saturation. Every day the parasite breeds unchecked, the problem grows harder to solve.
Officials are asking livestock owners across the region to inspect their animals daily for open wounds and signs of larval infestation. Any suspected cases should be reported immediately to the Texas Animal Health Commission. Early detection is the difference between a contained outbreak and a catastrophe.
The screwworm does not kill quickly. It feeds on living tissue, expanding the wound, attracting more flies, and weakening the animal over days. Left untreated, it is often fatal. In a herd of hundreds, a single missed case can seed an outbreak that spreads through an entire operation.
This is not a theoretical risk. It is happening now, in real counties, to real animals, on real ranches.
If the screwworm establishes itself in the southern United States, the consequences extend far beyond Texas. The American cattle industry, worth tens of billions annually, depends on the disease-free status that the 1966 eradication secured. A persistent screwworm population would trigger trade restrictions, increase veterinary costs, and reduce the value of American livestock on the global market.
The 1966 eradication campaign was one of the great success stories of American agricultural science. The sterile insect technique, developed by USDA researchers, eliminated a parasite that had tormented ranchers for generations. Maintaining that victory requires vigilance, and it requires a border secure enough to keep eradicated threats from walking back in.
Abbott and the Trump administration are responding with the urgency the situation demands. Whether it is enough depends on what the next thirty days reveal.
A flesh-eating parasite that America defeated sixty years ago has no business being back on U.S. soil. The fact that it is tells you something about what happens when borders go unguarded, not just against people, but against every threat that travels with them.
