Texas ag commissioner warns of screwworm threat 90 miles from border 

Texas Agriculture Commissioner Sid Miller is urging livestock producers to remain vigilant following confirmation of the northernmost detection of New World screwworm in Nuevo León, Mexico, about 90 miles from the U.S.-Mexico border. 

Miller described the pest as an immediate threat to Texas livestock and the broader food supply, warning that the situation requires urgent attention from producers and government agencies. 

“The New World screwworm is not some distant problem. It is a direct and imminent threat to Texas, and we are treating it that way,” Miller said in a statement. 

He said that while the U.S. Department of Agriculture has taken steps to respond, the spread of the pest has not yet been contained, raising concerns about its potential impact on the livestock industry. 

Miller called on producers to closely monitor their animals and report any unusual signs as quickly as possible, emphasizing that early detection is critical to preventing wider outbreaks. 

“There is zero margin for delay when it comes to screwworm,” he said. 

State officials are working with federal, state and local partners to address the situation, though Miller said additional efforts are needed to stop the spread at its source. 

The New World screwworm, a parasitic fly whose larvae feed on living tissue, was eradicated from the United States decades ago through a sterile insect technique. That approach remains central to current control efforts. 

USDA’s Agricultural Research Service is developing a male-only sterile fly strain that could increase production efficiency and improve containment strategies. The U.S. currently produces sterile flies in Panama and is investing $21 million to expand production capacity in Mexico. 

Officials say the goal is to suppress the pest population before it reaches U.S. livestock. 

Lacey Vilhauer can be reached at 620-227-1871 or [email protected].