By DTN Staff

OMAHA (DTN) -- USDA's National Veterinary Services Laboratories on Tuesday confirmed a sixth U.S. case of New World screwworm (NWS) in a calf in La Salle County, Texas, raising the total domestic case count as federal and state agencies escalate containment efforts across South Texas.

USDA's Animal and Plant Health Inspection Service (APHIS) is coordinating with the Texas Animal Health Commission (TAHC) on joint epidemiological investigations, case tracing, expanded surveillance, targeted trapping, and sterile insect releases in the La Salle County area, USDA stated in a news release on Tuesday.

NWS larvae feed on living tissue, causing severe wounds, animal suffering, and significant economic harm if not detected and treated quickly. The parasite also poses a threat to pets, wildlife, and, in rare cases, people, broadening the scope of the containment challenge beyond commercial livestock alone.

Joint federal-state field teams are already adjusting sterile insect release operations to maximize coverage as surveillance data develops in the area. APHIS and TAHC are also conducting direct outreach to ranchers, veterinarians, and local officials in affected areas, according to the news release.

APHIS urges all animal owners in the region to inspect animals immediately for draining or enlarging wounds, maggot or egg masses, signs of discomfort, and lesions around body openings including the nose, ears, genitalia, and umbilical area. Early detection and rapid reporting to a veterinarian, state animal health official, or USDA remain the most critical tools available to limit spread into new counties.

The U.S. food supply is not affected. NWS does not infest meat or food products, and any affected animal would be identified during USDA Food Safety and Inspection Service inspection before entering commerce.

For producers, immediate daily herd checks and prompt reporting of suspicious wounds are the most effective actions to protect herd health and contain spread.

-- Information supplied by USDA Animal and Plant Health Inspection Service.

Editor's Note: This article was produced with the assistance of artificial intelligence and reviewed by DTN editorial staff.

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For more DTN coverage of the New World screwworm threat and the response by the government and livestock industry, visit our Spotlight on New World Screwworm page at https://www.dtnpf.com/….

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