Follow-Up: Texas Modifies New World Screwworm Infested Zone 12.A, Easing Livestock and Pet Movement Rules in Parts of the Zone

TEXAS — The Texas Animal Health Commission (TAHC) has issued a new executive order modifying a New World screwworm (NWS) infested zone, with concurrence from the U.S. Department of Agriculture's Animal and Plant Health Inspection Service (APHIS), USDA announced on October 23. State and federal subject-matter experts confirmed that portions of the area met the requirements for zone release outlined in APHIS's New World Screwworm Response Playbook.
The zone being modified is Infested Zone 12.A. Releasing or modifying an infested zone removes NWS-related movement requirements for livestock and pets within certain areas, USDA said. All interstate movement requirements and international export requirements still apply.
Several infested zones in Texas remain in place, and APHIS continues to work closely with TAHC to evaluate conditions for future zone releases. USDA urged all Texas animal owners to visit the TAHC website for the latest information on zone locations, movement requirements and zone-specific rules, and pointed to screwworm.gov for updates on the response. APHIS and TAHC said they remain committed to supporting continuity of business for producers and will continue applying science-based surveillance, early detection and rapid-response measures so areas are released as soon as criteria are met.
The New World screwworm is a parasitic fly whose larvae feed on the living tissue of warm-blooded animals, threatening livestock and wildlife. GSM previously reported that USDA on October 21 confirmed the first detection of New World screwworm in U.S. wildlife, in a hunter-harvested elk in Pecos County, Texas, and on October 20 announced the continued phased reopening of southern border ports for livestock imports from Mexico. The zone modification is the latest development in that story.
Source: GSM · United States
Source: GSM · USA (original Chinese edition)
Photo: 图:美国农业部自然资源保护局(NRCS)工作人员与农场主查看牧场分区图(资料图)。美国农业部(USDA)公共领域图片,经 Wikimedia Commons 发布。 / An NRCS staffer and a producer review a pasture field map (file photo). U.S. Department of Agriculture, public domain, via Wikimedia Commons.
- 2026-10-18New World Screwworm Returns to the Southern U.S. as USDA Builds $750 Million Sterile Fly Plant in Edinburg, Texas
- 2026-10-20Follow-Up: USDA Continues Phased Reopening of Southern Border Ports, With Columbus, New Mexico Resuming Cattle Imports From Mexico on October 26
- 2026-10-21Follow-Up: New World Screwworm Confirmed in a Pecos County, Texas Elk, a First Detection in U.S. Wildlife
- 2026-10-22Follow-Up: New World Screwworm Confirmed in a Beef Cow in Otero County, New Mexico; Infested Zone of at Least 20 km Set Around the Site
- 2026-10-23Follow-Up: Texas Modifies New World Screwworm Infested Zone 12.A, Easing Livestock and Pet Movement Rules in Parts of the ZoneThis story
- 2026-10-24Follow-up: New Mexico Confirms New World Screwworm in a Hidalgo County Calf on Oct. 23, Setting a 12.4-Mile Infested Zone
- 2026-10-27Follow-Up: Two New World Screwworm Cases Confirmed in Doña Ana County, New Mexico; Livestock Board Expands Surveillance and Trapping
- 2026-10-28Follow-Up: First New World Screwworm Detection in Arizona Confirmed in a Cochise County Dog, USDA Sets 20-km Infested Zone

