US Confirms 5 Screwworm Cases in Livestock and Dog as Canada Restricts Texas Imports
Updated
Updated · WCTV · Jun 21
US Confirms 5 Screwworm Cases in Livestock and Dog as Canada Restricts Texas Imports
3 articles · Updated · WCTV · Jun 21
Summary
Five New World screwworm cases were confirmed by June 8 in three calves, a goat and a dog — the first U.S. cattle detections since 1982.
The cases span Texas and New Mexico, with the first two calves found less than 6 miles apart in Zavala County but later detections appearing up to 170 miles away and the dog linked to a veterinarian more than 400 miles away.
Canada responded on June 5 by banning entry of livestock that had been in Texas within the previous 21 days, reflecting fears the flesh-eating parasite could spread during summer transport.
The outbreak hits a beef sector already strained by a 75-year low U.S. cattle herd and record ground beef prices of $6.90 a pound in April, raising the risk of further supply losses and higher costs.
USDA says it is boosting border surveillance and sterile-fly production; the U.S.-Panama program now releases about 100 million sterile flies a week, the main tool used to suppress the parasite.
Did recent funding cuts and legislative debates weaken U.S. biosecurity, allowing this devastating livestock plague to return?
With beef prices already at record highs, could this flesh-eating fly outbreak make meat an unaffordable luxury?
A flesh-eating parasite has returned after 50 years. Is America's sterile fly defense system prepared for this new invasion?
New World Screwworm Crisis 2026: U.S. Outbreak, Economic Strain, and the Battle for Eradication
Overview
As of June 22, 2026, the re-emergence of New World screwworm (NWS) is a major concern in the United States, following a confirmed human case in August 2025 linked to travel from El Salvador. This highlights the risk of international transmission, especially as screwworm has reappeared in Central America and Mexico. The outbreak threatens public health, animal health, agriculture, the environment, and the economy. Authorities stress the urgent need for planning and preparedness to address these wide-ranging impacts and to protect the U.S. food supply and broader economy from further harm.