First U.S. Case of Flesh-Eating Screwworm in Texas Cattle Since 1966
The USDA confirmed New World screwworm in a Texas calf near La Pryor, the first U.S. livestock case since 1966. The parasitic fly lays eggs in open wounds, with larvae burrowing into living flesh, potentially killing hosts. A 12-mile quarantine zone was established, and the USDA is deploying sterile flies to contain the pest. The fly spread north through Mexico in 2024, prompting a livestock border closure. The $113 billion U.S. cattle industry is threatened, with the herd already at its smallest since the 1950s.
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Screwworm Cases Rise to 12 in US After DOGE Cut Monitoring Funding
The number of New World screwworm cases, a flesh-eating parasite, has risen to 12 across Texas and New Mexico, affecting cattle, goats, sheep, and dogs. The outbreak follows funding cuts by Elon Musk's Department of Government Efficiency (DOGE) to a USAID monitoring program in Central America. Agriculture officials and ranchers had warned the parasite was moving north through Mexico but were ignored. The US cattle herd is at its lowest in 75 years, and experts warn a wider outbreak could drive up beef prices, which have already risen 75% since 2020. The USDA urges animal owners to watch for signs of infection, and containment measures may include movement restrictions and quarantines.
Forbes - BusinessU.S. Sterile Fly Facility Delayed Until 2027, Risking Wider Screwworm Outbreak
The United States' primary tool against a New World screwworm outbreak in Texas cattle—a sterile fly breeding facility at Moore Air Base—will not begin operations until November 2027, leaving a critical gap in containment efforts. The parasite, which infests wounds of warm-blooded animals, has been detected in six cattle in Texas, the first U.S. livestock cases in 50 years. Currently, only a Panama facility produces 100 million sterile flies weekly, far below the estimated 500 million needed. A Mexican plant may double output by summer 2025, but full capacity remains years away. Agriculture Secretary Brooke Rollins acknowledged eradication is impossible without more flies but expressed hope for containment. The outbreak threatens a cattle industry already at a 75-year herd low due to drought and high costs, potentially driving beef prices higher. Texas officials have criticized the USDA's response and called for alternative bait systems.
Fortune | FORTUNETexas Agriculture Commissioner Sid Miller Blasts USDA Over Flesh-Eating Screwworm Threat to Beef Supply
The New World screwworm fly, a flesh-eating parasite, has reemerged in Texas for the first time since 1966, threatening the U.S. cattle industry with millions in potential losses. Texas Agricultural Commissioner Sid Miller, a Trump loyalist, publicly criticized the USDA's response, accusing the department of moving too slowly and relying on an outdated 'sterile insect release' method. Miller argues the technique is ineffective because sterile males and females are released together, mating with each other instead of wild flies. He also claims USDA quarantine policies discourage farmers from reporting cases. The USDA has set up quarantine zones and is ramping up sterile fly production. The outbreak has also spread to New Mexico. Miller linked the crisis to higher beef prices, blaming the USDA rather than the Iran war or Trump's tariffs.
Fortune | FORTUNENew World screwworm spreads from Texas to New Mexico, threatening US cattle industry
The New World screwworm, a flesh-eating fly larva that infests open wounds in warm-blooded animals, has spread from Texas to New Mexico, with five confirmed cases as of June 2026: three calves and a goat in Texas, and a dog in Lea County, New Mexico. The USDA has established 12-mile quarantine zones around each case and is ramping up a sterile male fly release program to combat the pest, which could devastate the US cattle industry and wild deer populations. Canada has temporarily halted livestock imports from Texas. Scientists expect more cases but note increased vigilance may explain the rise. The long-term solution—breeding enough sterile flies—is months away, with a goal to halt the pest by 2027.
Fortune | FORTUNEUSDA Secretary Says Food Supply Not at Risk After New Texas Screwworm Cases
USDA Secretary Brooke Rollins stated that the U.S. food supply is not at risk following the confirmation of multiple New World screwworm cases in Texas, the first since the 1960s. The parasitic fly larvae burrow into living warm-blooded animals, posing a threat to livestock and pets but not to food products. Rollins announced a response plan involving the release of approximately 10 million sterile flies per week, echoing successful eradication efforts from the late 1950s. The USDA confirmed four total cases, including a dog recently in Mexico. Rollins defended the response speed against criticism from Texas Agriculture Commissioner Sid Miller, emphasizing a $1 billion investment to push the pest back into Mexico and achieve eradication.
US Top News and AnalysisScrewworm Cases Rise to 4 in Texas, Threatening to Drive Up Beef Prices After Funding Cuts
The USDA confirmed four cases of New World screwworm in Texas, including three cattle and a dog, marking the return of a flesh-eating parasite largely eradicated from U.S. livestock in the 1960s. The outbreak follows funding cuts by the Musk-led Department of Government Efficiency (DOGE) to a USAID monitoring program in Central America. Texas Agriculture Commissioner Sid Miller said ranchers' warnings about the parasite moving north through Mexico were ignored. The U.S. cattle herd is already at its lowest level in 75 years, and beef prices have risen roughly 75% since December 2020. A wider outbreak could cause calf deaths, weight loss in adult cattle, and movement restrictions, further straining supply and driving prices higher. The parasite lays eggs in open wounds, and larvae feed on living flesh. The U.S. previously eradicated screwworm through a $42 million sterile fly program.
Forbes - BusinessFlesh-Eating Screwworm Fly Reaches Texas, Threatening $113 Billion Cattle Industry
The New World screwworm fly, a flesh-eating parasite, has been confirmed in a calf in La Pryor, Texas, marking the first infestation in the state since 1966 and the first U.S. case in over half a century. The fly, which lays eggs in open wounds of warm-blooded animals, threatens the $113 billion U.S. cattle industry, with Texas alone valued at $17 billion. The USDA is responding by dropping 4 million sterile male flies weekly from planes to disrupt reproduction, a strategy that successfully eradicated the pest in the U.S. in the 1960s. The fly was detected in Mexico in late 2024 after being contained in Panama. As of June 2, 2026, the parasite has sickened over 171,700 animals and 2,000 people across Central America and Mexico, with 10 human deaths. U.S. Agriculture Secretary Brooke Rollins closed livestock border entries in May 2025, delaying the fly's arrival by a year. Officials cite climate change as a factor in the tropical species' northward spread.
Fortune | FORTUNEFlesh-eating screwworm found in Texas calf, first US livestock case since 1960s
The U.S. Department of Agriculture confirmed the first case of New World screwworm in U.S. livestock since 1966, found in a calf in south Texas. The flesh-eating parasite, which lays eggs in open wounds and can kill hosts if untreated, poses no food safety risk but threatens the cattle industry. The U.S. had already sealed its southern border to livestock in 2024 as the parasite spread through Mexico. In response, the USDA established a 12.4-mile quarantine zone, increased monitoring, and plans to release millions of sterile screwworm flies to contain and eradicate the infestation. The nation's cattle herd is already at its smallest since the 1950s, raising concerns about potential economic impact.
TheWeek feedFlesh-eating screwworm found in Texas calf, first US livestock case since 1960s
The U.S. Department of Agriculture confirmed the first case of New World screwworm in U.S. livestock since 1966, found in a calf in south Texas. The flesh-eating parasite, whose larvae burrow into living flesh, poses no food safety risk but could devastate the American cattle industry if it spreads. The U.S. had been preparing for its arrival by sealing the southern border to livestock after the parasite spread through Mexico in 2024. Agriculture Secretary Brooke Rollins announced immediate containment measures, including a 12.4-mile quarantine zone, increased monitoring, and release of sterile screwworm flies to shrink the population. The nation's cattle herd is already at its smallest since the 1950s.
TheWeek feedFlesh-eating screwworm found in Texas calf, first US livestock case since 1960s
The U.S. Department of Agriculture confirmed the first case of New World screwworm in U.S. livestock since 1966, found in a calf in south Texas. The parasitic fly lays eggs in open wounds of warm-blooded animals, and the larvae burrow through living flesh, potentially killing the host if untreated. Human cases are rare and the fly poses no food safety issues. The U.S. had been preparing for the parasite's arrival after it spread north through Mexico in 2024, leading to a livestock border closure. The USDA established a 12.4-mile infested zone quarantine, increased monitoring, and plans to release millions of sterile screwworm flies to contain and eradicate the case. The discovery could further devastate the American cattle industry, which is already at its smallest herd size since the 1950s.
TheWeek feedFlesh-eating screwworm fly detected in Texas cattle for first time in decades
The U.S. Department of Agriculture confirmed the first case of New World screwworm fly in Texas cattle since 1966, found in a 3-week-old calf near LaPryor, Texas, about 50 miles from the Mexico border. Texas State Veterinarian Bud Dinges established a 12-mile quarantine zone prohibiting movement of warm-blooded animals without inspection. Agriculture Secretary Brooke Rollins stated there have been no other U.S. detections and that properly treated calves can recover. The fly, which lays eggs in open wounds and whose larvae eat flesh, was eradicated from the U.S. in the 1970s but has been moving north through Mexico. The USDA has deployed 8,000 fly traps, tested thousands of samples, and is building a $750 million sterile fly factory in Texas. Officials believe the incursion will not lead to establishment of the pest.
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