A cow grazes in farmer Randy Edwards’ field on June 02, 2026 in Quemado, Texas. <\/p>\n
Brandon Bell | Getty Images<\/p>\n
Samples of an unconfirmed infestation of the flesh-eating screwworm \u200bparasite on a cattle ranch in La \u200bPryor, Texas, have been \u200bsent to a federal government lab in Iowa to be tested, Texas Representative Don McLaughlin said Wednesday. <\/p>\n
The samples were taken from two calves on the same ranch on Tuesday, McLaughlin said, adding that he had seen photos and videos of the \u2060animals. <\/p>\n
Widespread \u200cmarket chatter about the suspected case hung over cattle futures, which \u2060traders said have long been sensitive to threats of New World screwworm. The parasite has been moving north through Mexico for more than a year. <\/p>\n
Market players believe a screwworm infestation in the U.S. could reduce demand for beef from consumers nervous about the flesh-eating \u200cpest but would be bullish in the long term by reducing the U.S. cattle supply. <\/p>\n
The photo, seen by Reuters, shows multiple larvae resembling the screwworm inside a bloody circular wound on an \u200banimal. <\/p>\n
McLaughlin said one of the suspected infestations was detected in an umbilical cord wound of a calf, though it was unclear if that was the case seen in the photo. Reuters could not immediately verify the photo.<\/p>\n
“At this point, it’s unconfirmed that it’s the New World Screwworm,” McLaughlin said. “It looks \u2060like it, but it’s unconfirmed.” The Texas Animal Health Commission told Reuters on Wednesday that there has been no confirmed case of New \u200cWorld screwworm in Texas. <\/p>\n
The U.S. Department of Agriculture, which is leading \u200cthe screwworm prevention effort in the United States, did not immediately respond to a request for comment.<\/p>\n
“NWS is not currently present in the United States,” the agency’s website said Wednesday. Screwworms are parasitic flies whose females lay eggs in wounds on any warm-blooded animal. \u2060Once the eggs hatch, hundreds of screwworm larvae use their sharp mouths to burrow through living flesh, \u2060eventually killing their host if left untreated. <\/p>\n
An outbreak of screwworm in the U.S. could \u2060cause $1.8 billion in damage to Texas’ economy alone and would likely raise U.S. beef prices by shrinking the U.S. cattle supply, experts have said.<\/p>\n
Earlier in the week the USDA \u200bsaid that McLaughlin, who had said that a case was \u200cconfirmed one mile south of the Texas border, had inaccurate information. The USDA confirmed a case 25 miles south of the Texas border in Coahuila state on Tuesday.<\/p>\n
Washington has kept its border closed to cattle imports for more than a year in an effort to prevent the destructive parasite from reaching U.S. border states. The United States has spent millions of dollars \u200bto slow its advance through Mexico, investing in \u200csterile fly production facilities, expanding trapping efforts and increasing livestock surveillance.<\/p>\n