Second flesh-eating screwworm infection reported in cattle in Texas

A Texas official works during the state’s response to the screwworm infestation, in Austin, Texas, on 5 June 2026. Photograph: Jay Janner/Austin American-Statesman/AP View image in fullscreen A Texas official works during the state’s response to the screwworm infestation, in Austin, Texas, on 5 June 2026. Photograph: Jay Janner/Austin American-Statesman/AP Second flesh-eating screwworm infection reported in cattle in Texas Governor issued disaster declaration as agencies move to stop spread of parasite, including release of sterile flies A second case of the flesh-eating screwworm fly has been confirmed in Texas by the US Department of Agriculture (USDA), days after an initial case in a one-year-old calf set off an aggressive response to stop the spread of the parasite in the dominant cattle-producing state. Texas’s governor, Greg Abbott , said on Friday that state officials were working with the federal government to slow the spread of the fly and the infestations caused by larvae that feed on the living flesh of warm-blooded animals and humans. Officials are dispersing millions of sterile screwworm flies in the vicinity of where the twin infections were found about five miles apart in Zavala county, south-west of San Antonio. Those sterile male flies would prevent wild female flies from reproducing. Alarm as once-eradicated flesh-eating parasite found in calf in Texas Read more The infections of the new world screwworm (NWS) are the first detected in the US since the 1960s. The USDA confirmed the second case. The first case was confirmed by the Texas animal health commission (TAHC) on Wednesday after NWS was detected in a three-week-old calf with an umbilical lesion. “This is the first detection of NWS in Texas since northward progression from Central America was observed in 2023,” the commission said in a news release , adding that an infested zone has been established in the area. The commission also said that animal movement restrictions were in effect to prevent further spread of the pest. According to the USDA, the US food supply is safe, and it noted that NWS do not infest meat, fruits, vegetables or other food sources. NWS are parasitic larvae or maggots of the NWS fly ( Cochliomyia hominivorax ). They cause a painful condition called NWS myiasis. When the fly’s eggs hatch, larvae burrow through living flesh, killing their host if left untreated. “TAHC has been actively preparing for a resurgence of NWS for over two years,” the commission’s director, Dr Bud Dinges, said. “We are putting these preparations into action, and we encourage all animal owners and caretakers to continue to remain vigilant for the presence of larvae in animal wounds and immediately report any suspicions.” The TAHC said that the introduction of sterile flies, when combined with enhanced surveillance, movement restrictions, prompt treatment of wounds, and education and outreach efforts, “is a proven and effective tool for controlling and eradicating this pest”. Abb