APHIS releases 2 Texas zones from New World screwworm restrictions

The US Department of Agriculture's (USDA’s) Animal and Plant Health Inspection Service (APHIS) has approved the release of 2 New World screwworm (NWS) infested zones in Texas, the agency announced August 31, 2026.¹ It is the first NWS infested-zone release in the state since the first case was detected on June 3.¹

"The Texas Animal Health Commission has been an outstanding partner throughout our response to New World screwworm," Dudley Hoskins, USDA under secretary for marketing and regulatory programs, said in the announcement.¹

The decision followed concurrence from Texas State Veterinarian Bud Dinges, DVM, and the Texas Animal Health Commission (TAHC).¹ The 2 zones being released are Infested Zone 02.A, which includes portions of La Salle and Webb counties, and Infested Zone 03, which includes portions of Gillespie, Kerr, and Kimble counties.¹

What the release changes

State and federal experts confirmed both zones met all requirements in APHIS' New World Screwworm Response Playbook before the release was approved, according to the agency.¹ Response activities conducted jointly by TAHC and APHIS in the zones included establishing domestic animal movement requirements with inspections, wildlife and fly surveillance, and strategic releases of sterile NWS flies.¹

Releasing the zones removes NWS-related movement requirements for livestock and pets within their boundaries. All non-NWS interstate movement requirements and international export requirements remain in effect, APHIS said.¹ Several infested zones in Texas remain in place, and the agency said it will continue working with TAHC to evaluate conditions for additional releases.¹

Background on the outbreak

APHIS confirmed the first US case in the outbreak on June 3, 2026, identifying NWS larvae in the umbilical region of a 3-week-old calf in Zavala County.² In response, USDA and Texas officials established a 20-kilometer infested zone with quarantines and movement controls, began ground-based releases of sterile flies alongside existing aerial releases of 4 million sterile flies weekly, and intensified border surveillance and wildlife management.²

"The United States has defeated this pest before, and we will do it again," Hoskins said at the time.²

NWS larvae burrow into the living flesh of warm-blooded animals through open wounds, causing tissue damage that can be fatal to livestock, pets, and wildlife if untreated, according to APHIS.² The agency has said screwworms do not contaminate meat or other food products, and Food Safety and Inspection Service protocols are designed to identify infected animals before they enter the commercial supply.²

References

1. APHIS approves release of New World screwworm infested zones in Texas. News release. US Department of Agriculture Animal and Plant Health Inspection Service. August 31, 2026. Accessed September 2, 2026. https://www.aphis.usda.gov/news/agency-announcements/aphis-approves-release-new-world-screwworm-infested-zones-texas
2. USDA confirms presence of New World screwworm in the United States. News release. US Department of Agriculture Animal and Plant Health Inspection Service. June 3, 2026. Accessed September 2, 2026. https://www.aphis.usda.gov/news/agency-announcements/usda-confirms-presence-new-world-screwworm-united-states