Second Case of New World Screwworm Confirmed in Texas, USDA Steps Up Response

The U.S. Department of Agriculture (USDA) confirmed a second case of New World screwworm in Texas on June 6, 2026, marking a renewed effort to contain the infestation that has resurfaced after decades of eradication. The second case was detected in Zavala County, Texas, approximately 5.6 miles from the first case, which was identified in a three-week-old calf just days prior.

USDA Response and Control Measures

The USDA has escalated surveillance efforts in response to the second case, emphasizing a multi-pronged approach to prevent the spread of the infestation. According to the agency, control measures include trapping flies for testing, establishing detection and quarantine zones, and releasing sterile flies to disrupt breeding cycles. “With our partners in Texas, we are responding with speed and strength,” the USDA stated in a public release. “We have defeated this pest before, and we will do it again.”

The agency also urged residents in the affected areas to monitor livestock and pets for signs of infection, such as draining wounds, enlarging sores, or the presence of maggots or eggs near bodily openings. While human infections are rare, the USDA highlighted the importance of seeking immediate medical attention if symptoms arise.

Historical Context of New World Screwworm

New World screwworm, a parasitic fly species, was eradicated from the United States in the 1960s through a combination of insecticides and sterile insect technique (SIT). However, the pest has reemerged in recent years, with infestations detected in Central America and gradually moving northward. The first confirmed case in the U.S. was reported in 2025, according to the USDA, raising concerns about its potential spread along the southern border.

Historically, the SIT program has proven effective in managing screwworm outbreaks. The USDA’s current strategy mirrors the methods used in the 1960s, leveraging scientific advancements to minimize economic and health risks to livestock and wildlife.

Community and Industry Impact

The resurgence of New World screwworm has prompted warnings from agricultural officials about the threat to Texas’s livestock industry. The USDA has pledged full support to producers, stating that “America’s livestock producers have USDA’s FULL support.” Local farmers and ranchers are advised to remain vigilant, as the infestation could impact cattle, poultry, and other animals.

Public health officials have also emphasized the importance of early detection, noting that while human infections are uncommon, they can occur through exposure to contaminated wounds or open sores. The USDA has launched a public awareness campaign to educate communities on identifying and reporting suspected cases.

What’s Next?

The USDA is closely monitoring the situation, with plans to expand surveillance efforts in neighboring counties. The agency has also partnered with state and local authorities to ensure rapid response to any new cases. “Our priority is to prevent the infestation from gaining a foothold in the U.S.,” a USDA spokesperson said. “We are prepared to take all necessary steps to protect agriculture and public health.”

As the second case highlights the ongoing threat of New World screwworm, the USDA’s actions underscore the importance of sustained vigilance and collaboration between federal agencies, farmers, and the public.