AUSTIN, Texas — The U.S. Department of Agriculture confirmed a second case of New World screwworm in Zavala County on Friday, hours after Texas Gov. Greg Abbott expanded a statewide disaster declaration in response to the pest’s detection in the state.
The USDA said in a social media post that officials found the second case in a one-month-old calf located 5.6 miles from the site of the first confirmed case earlier in the week. The agency said it deployed mobile response teams and increased surveillance in the area following the detection.
Abbott signed the expanded disaster declaration during a news conference in Austin. The order authorizes the use of all state resources to respond to the outbreak and directs agencies to reassign personnel, including staff from university systems, to support response efforts such as sterile fly shipments and construction of a production facility in South Texas.
The governor said the state is prioritizing Zavala County and nearby Uvalde County and is coordinating with federal officials on containment and response measures.
The USDA established a 20-kilometer infested zone around the affected area, restricting the movement of animals without inspection, and created a wider surveillance zone that includes surrounding counties.
Abbott said state agencies will support the response without requiring additional funding, while federal authorities continue financing key infrastructure projects, including sterile fly production facilities.
He said officials are accelerating efforts to complete a Texas-based sterile fly facility, which is intended to help control the pest by disrupting its reproduction cycle.
USDA officials said the federal response includes deployment of sterile flies, increased field operations, and ongoing collaboration with local partners. The agency said it has already released more than 130 million sterile flies in Texas since January.
The screwworm, a parasitic fly that can infest wounds in livestock and wildlife, is expected by federal officials to continue spreading in warmer months. The USDA estimated that a wider outbreak could cause up to $1.8 billion in economic losses to Texas’ livestock industry.
State and federal officials have said the infested calf identified in Zavala County showed no additional cases within its herd following inspection.
Local officials in South Texas have raised concerns about communication from federal authorities, saying they lack detailed information about confirmed cases and surveillance zones.
Some ranchers also expressed concern about potential impacts on livestock and wildlife, including deer populations that support hunting industries in the state.
The USDA said its strategy relies on the release of sterile male flies, which mate with wild females and prevent reproduction. Federal officials said they plan to expand dispersal operations in affected regions while additional production facilities are completed in Texas and Mexico.