Thirty-one new New World screwworm infestations were confirmed in Texas, plus one in New Mexico, with Texas cases spread across 12 counties and 23 premises.
Twenty-one Texas counties are now under movement restrictions, requiring inspections before warm-blooded animals can leave, while all southern ports of entry remain closed to livestock trade.
The latest confirmed case was a sheep in Crockett County on July 3, and infected animals cannot be sold or processed for meat.
Texas officials say the parasite spread north after nearly 28,000 cases were detected in Mexico since November 2024, raising risks to the state's $41 billion cattle industry and potentially higher beef prices.
Gov. Greg Abbott urged livestock owners to check animals daily for worsening wounds or visible larvae, treat injuries quickly and report suspected infections immediately to the Texas Animal Health Commission.
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Screwworm Returns: Tracking the 2026 Outbreak, Livestock Risks, and the Federal $100 Million Response
Overview
In July 2026, the New World screwworm reemerged in the United States, posing a serious threat to animal health and a rare but significant risk to humans. This outbreak began with an initial detection in Panama and Costa Rica in 2023, then spread across Central America and Mexico—regions where the parasite was previously under control—before crossing into Texas. The rapid and critical development of the screwworm’s spread highlights major concerns about its geographic expansion and the challenges of containing such a dangerous pest, emphasizing the urgent need for coordinated response and vigilance.