Flesh-Eating Fly Hits Texas

Veterinarian in protective gear examining a chicken in a poultry farm

A flesh-eating livestock parasite once wiped out in America is back in Texas, and what happens next will hit ranchers, grocery bills, and border policy all at once.

Story Snapshot

A confirmed New World screwworm case in a Texas calf marks the parasite’s return to U.S. soil in decades.
Federal and Texas teams are rolling out checkpoints, livestock movement controls, and mass sterile-fly releases to stop a wider outbreak.
Officials say the food supply and human risk remain low, but the economic stakes for cattle and wildlife are huge.
The crisis exposes years of border failures as the pest marched north through Central America and Mexico before crossing into Texas.

What the New World screwworm is and why ranchers are alarmed

The New World screwworm is a parasitic fly whose larvae burrow into the flesh of living warm‑blooded animals and eat them from the inside out, often killing untreated livestock.^[20] The U.S. Department of Agriculture (USDA) says it is a “serious pest” that harms cattle, pets, wildlife, and in rare cases, people.^[1] On June 3, 2026, USDA confirmed the parasite in a three‑week‑old calf in Zavala County, Texas, with larvae found in its navel, a classic target on newborn animals.^[1] That single confirmation matters because screwworm once caused massive losses before it was eradicated in the 1960s.^[21]

In recent years, the parasite has surged north through Central America and into Mexico, following the same corridor as illegal migration and livestock movement.^[3] Since 2023, more than 185,000 animal cases and over 2,100 human cases have been reported in the region.^[3] Texas and other southern states sit in the danger zone because they have warm climates and large cattle and wildlife populations that give screwworm plenty of hosts.^[6] Experts warn that if the pest establishes itself again in the U.S., the economic and ecological damage would be severe and long‑lasting.^[2]

How the government is responding on the ground

USDA’s Animal and Plant Health Inspection Service says it is following its screwworm “Response Playbook,” which includes aggressive surveillance, movement controls, and rapid treatment of suspect animals.^[1] Governor Abbott and USDA Secretary Rollins say teams are in the field in Texas, setting up checkpoints, trapping flies, and working directly with landowners for inspection and control work.^[2] They report ground and aerial release of up to four million sterile screwworm flies in the affected zone to crash the wild population by blocking reproduction.^[2]

Federal health guidance stresses that this is not a food‑safety crisis and that meat from inspected animals remains safe to eat.^[1]^[17] The Centers for Disease Control and Prevention (CDC) notes that there are no locally acquired human cases tied to this outbreak so far and that the risk to people remains low and focused on areas where the flies are active.^[3] That means the immediate danger is to animals and the rural economy, not to shoppers picking up beef at the store. But ranchers are being told to check every animal often for foul‑smelling wounds, maggots, or signs of distress and to report anything suspicious right away.^[4]^[8]

Economic stakes and the cost of letting the border problem fester

Texas A&M experts estimate that if screwworm gains a foothold in the state, it could cost about 2.1 billion dollars to the cattle industry and 9 billion dollars to hunting and wildlife interests in Texas alone.^[12] Historically, screwworm outbreaks have caused major livestock deaths and forced expensive emergency campaigns using pesticides and sterile insects.^[18]^[26] A recent review of U.S. screwworm risk notes that while human danger stays low, agricultural losses can be huge if detection or response is slow.^[14] That is why many ranchers view this as an economic emergency, even as officials urge the public not to panic.

🚨New World Screwworm Update🚨
15 cases have been confirmed in total across the U.S, with 12 cases active in Texas. We have been preparing for this, and I am working with USDA @SecRollins to combat this pest, protect our livestock industry, and mitigate economic impacts. Read the…

— Rep. Monica De La Cruz (@RepMonicaDLC) June 22, 2026

Conservatives will see another pattern here: a foreign threat walking right up the southern border after years of warnings. CDC documents show the outbreak marched north through Central America and into Mexican states that share a border with Texas before the U.S. ever saw a case.^[13] USDA had already suspended imports of cattle, horses, and bison from Mexico last year because of detections there.^[12] For rural Texans who have watched waves of illegal crossings and disease risks, this parasite looks like one more cost of a border that Washington allowed to stay porous for too long.

What comes next for ranchers, families, and Trump’s Washington

Going forward, USDA’s unified screwworm site says eradication depends on three main tools: tight animal‑movement controls, intense field surveillance, and sustained sterile‑fly releases over many months.^[7] Experience from past outbreaks shows these campaigns can work but take time, money, and discipline across agencies and state lines.^[21]^[24] Under President Trump’s second term, the pressure will be on federal leaders to back tough border enforcement and strong agricultural defenses at the same time, instead of choosing one or the other.

For now, health and agriculture officials give two clear messages. First, the U.S. food supply remains safe, and the average American’s personal health risk is low.^[7]^[10] Second, ranchers, pet owners, and hunters in affected regions must stay alert, inspect animals, treat wounds fast, and report problems without delay.^[4]^[8] That kind of local vigilance, backed by a serious federal push, is how America beat screwworm once before. The question this time is whether our leaders have learned enough from years of border and biosecurity failure to finish the job again.