Texas Agriculture Commissioner Sid Miller on Dec. 31, 2025, responded to confirmation from Mexico’s National Service of Agro-Alimentary Public Health, Safety, and Quality of a New World screwworm (NWS) case detected Dec. 27 in a six-day-old calf in Tamaulipas, Mexico, about 197 miles from the U.S.-Mexico border.
The finding marks the first reported case in Tamaulipas and the northernmost active detection to date. Miller called the discovery a “grim reminder” of the serious threat the pest poses to Texas livestock, while crediting coordination between Mexico and the USDA for halting its northward spread so far. Still, Miller stressed that eradication depends on deploying sterile flies to eliminate the parasite at its source.
More information is available at screwworm.gov.
