The U.S. Department of Agriculture (USDA) confirmed the presence of the New World screwworm in a calf located in south Texas, marking the first detection of this flesh-eating parasite in U.S. livestock since 1966. The screwworm, a parasitic fly, lays eggs in open wounds on warm-blooded animals, leading to the hatching of larvae that burrow through living flesh, potentially resulting in death if untreated. Although human cases are rare, the parasite poses a significant threat to livestock. The USDA has taken immediate action by establishing a 12.4-mile quarantine zone around the infected calf and is increasing monitoring efforts. They plan to release millions of sterile screwworm flies to control the population. Agriculture Secretary Brooke Rollins warned that if more cases are identified, it could severely impact the already diminished U.S. cattle herd, which is at its lowest level since the 1950s. The U.S. has been proactively preparing for the screwworm's arrival since its detection in Mexico in 2024.