APHIS confirms New World screwworm in Texas calf; food supply safe

The Agriculture Department’s Animal and Plant Health Inspection Service confirmed the detection of a New World screwworm (NWS) late Wednesday in a 3-week-old calf in Zavala County, Texas.

NWS is a serious pest that affects livestock, pets, wildlife and, less commonly, people and birds. But “the U.S. food supply is safe. Screwworms do not infest meat, fruits, vegetables, or other food sources,” APHIS noted in a news release.

Julie Anna Potts, president and CEO of the Meat Institute, which represents meat processors, said in a news release, “American consumers need to know that New World screwworm is not a food safety concern. Meat and poultry products are safe to consume. Our first priority is to protect the health of the nation’s livestock. We are encouraging members of the Meat Institute to work with local, state and federal authorities to detect and eradicate the pest. We will look to USDA to brief industry stakeholders and call on them to consider allowing low-risk terminal movements for slaughter to ensure animals continue to be processed.”

New World screwworm had been moving steadily northward but was not found within the United States until this week.

The affected animal is a 3-week-old calf, and larvae were identified in its umbilical area. To date, there have been no further detections.

APHIS explained, “NWS larvae (maggots) burrow into the flesh of living animals, causing serious damage to livestock and economic losses,” APHIS said in a news release. “NWS maggots can infest livestock and other warm-blooded animals, including, in rare cases, people. They most often enter an animal through an open wound and feed on the animal’s living flesh. USDA urges residents in the area to check their pets and livestock for signs of NWS. Look for draining or enlarging wounds and signs of discomfort. Also look for screwworm larvae (maggots) and eggs in or around body openings, such as the nose, ears, and genitalia or the navel of newborn animals. If you suspect your animal is infected with screwworm, contact your state animal health official or USDA area veterinarian in charge immediately. While not common in people, if you notice a suspicious lesion on your body or suspect you may have contracted screwworm, seek immediate medical attention.”

Agriculture Undersecretary for Marketing and Regulatory Programs Dudley Hoskins and Senate Agriculture Committee Chairman John Boozman, R-Ark., and House Agriculture Committee Chairman Glenn “GT” Thompson, R-Pa., and farm and meat leaders said the Trump administration had been working for the past year to keep New World screwworm out of the United States as long as possible and prepare for the eventuality that screwworm would enter the country.

“All models showed New World screwworm entering the country in 2025; however, thanks to the hard work across the entire Trump administration and our industry, state, and local partners, we were able to buy time for this moment. Protecting our livestock industry is a national security issue of the utmost importance, and USDA is wasting no time in taking action,” Hoskins said in the release. “USDA invested heavily in the tools needed to eliminate NWS ever since cases started increasing in Central America and Mexico. The United States has defeated this pest before, and we will do it again.”

In a news release, Boozman and Thompson said, “For well over a year, Secretary Brooke Rollins and her team at USDA have been working around the clock alongside federal agencies, state partners and animal health experts to prevent New World screwworm from entering the United States — longer than many thought possible — and to ensure we are prepared to respond to a potential domestic case. Their proactive efforts have strengthened our defenses against this serious threat to animal health and the livestock industry, and we appreciate their continued commitment to protecting American agriculture.

“The detection of New World screwworm within our borders should not be cause for panic, but rather time for the full deployment of the next phase of the whole-of-government response USDA has been planning for months. We have the tools, resources and an action plan to aggressively respond, enhance surveillance and prevent further spread. By working closely with producers, animal health officials, and our federal and state partners, we will take the necessary steps to protect and safeguard America’s livestock industry. We have successfully eradicated this threat to livestock, wildlife and animal health before, and we’re confident we will do so again.”

American Farm Bureau Federation President Zippy Duvall said, “The re-emergence of New World screwworm in the United States after 60 years will have an immediate impact on farmers and ranchers in the affected areas. We are confident that the longstanding coordination between the states and USDA will enable a quick response and hopefully limit the negative impacts and resulting market volatility.

“We encourage farmers, ranchers and pet owners to familiarize themselves with the signs of NWS and notify a veterinarian if infection is suspected. It is important to be clear about the fact that this re-emergence does not threaten the safety of our food supply. We are fortunate to have one of the safest food supplies in the world, which includes multiple layers of protection.

“We knew the screwworm could one day migrate north, and we appreciate USDA and Secretary Rollins for the coordination and mitigation efforts that have already occurred. Farm Bureau is committed to working with USDA and the affected areas in any way to eliminate this pest once again from the U.S.”

National Cattlemen’s Beef Association CEO Colin Woodall said, “We defeated this harmful pest before in the 1960s by investing heavily in sterile fly dispersal, and NCBA will continue using every tool in the toolbox to ensure [NWS] is eradicated in the U.S. once again.”

The U.S. Cattlemen’s Association said it “commends USDA’s Animal and Plant Health Inspection Service and the Texas Animal Health Commission for their swift response to this potential detection and for their extensive work on the ground to hold off the reemergence of New World screwworm through 2025 and into the first half of 2026. Their early activation of personnel in the region, close coordination with state and local partners, and continued focus on prevention, early detection, and rapid response have bought producers and animal health officials critical time to prepare for a situation just like this.”

National Milk Producers Federation President and CEO Gregg Doud said, “Now that USDA has confirmed that screwworm is here, dairy farmers and all livestock producers pledge close collaboration with USDA, state and local officials, and producer organizations to mitigate any harmful effects and educate farmers on how to protect their herds. We have been creating resources to guide farmers in their responses, and we will keep our members well informed of any important screwworm developments.

“We also urge officials to follow scientific guidance in any decisions affecting animal movements and regulatory responses to avoid causing economic harm that could be greater than the screwworm itself. We also ask that adequate resources be provided to combat this problem, which causes suffering in animals and creates risk for producers.”