09/22/2025
On September 21, a new case of New World screwworm in Sabinas Hidalgo, located in the state of Nuevo León, was detected by Mexico’s National Service of Agro-Alimentary Health, Safety, and Quality (SENASICA).
This is now the northernmost detection of NWS during this outbreak. Sabinas Hidalgo is located near a major highway that runs from Monterrey, Nuevo Leon, to Laredo, Texas, which is one of the most heavily trafficked commercial thoroughfares in the world, according to the U.S. Department of Agriculture press release.
The previous northernmost detection was reported on July 9, in Veracruz, approximately 300 miles farther south. Preliminary reports from SENASICA indicate that the affected animal—an 8-month-old cow—had recently been moved to a certified feedlot in Nuevo León from a region in southern Mexico with known active NWS cases.
New World screwworm has been detected closer than ever to the U.S.-Mexico border. As health officials continue preventive efforts, they stress that veterinarians’ vigilance is also crucial to prevent the parasite from re-establishing itself in the U.S.
