U.S. Department of Agriculture officials confirmed a New World screwworm fly case in south Texas on June 3, 2026 [4].
The discovery of this flesh-eating parasite poses a significant threat to livestock and food production. Because the parasite can devastate animal populations, federal and state authorities are moving quickly to prevent a wider outbreak.
To contain the spread, the Texas state veterinarian established a quarantine zone with a 12-mile radius [1]. This measure aims to isolate the affected area and prevent the parasite from migrating to other regions of the state, or across state lines.
The case was detected in south Texas near the U.S.-Mexico border. Reports on the exact proximity of the detection vary, with some indicating the site is about 25 miles from the border while others suggest it may be as close as one mile away [2, 3].
USDA officials and state veterinarians are monitoring the region to identify any further infestations. The New World screwworm is known for invading the living tissue of warm-blooded animals, making rapid containment essential for the agricultural economy.
While some reports characterized this as a first possible U.S. case [5], previous records indicate travel-associated human cases have occurred in the past. However, the current situation in south Texas represents a critical point of concern for livestock management and regional biosecurity.
“The discovery of this flesh-eating parasite poses a significant threat to livestock and food production.”
The emergence of the New World screwworm in a border region highlights the ongoing vulnerability of the U.S. agricultural supply chain to invasive species. If the quarantine fails to contain the parasite, the resulting livestock losses could lead to increased meat prices and stricter trade restrictions on animal products moving across the border.
