The rapid spread of New World screwworm across Texas is escalating concerns about the state’s livestock industry and testing an emergency campaign to contain a parasite once eradicated from the United States.
As of Monday afternoon, federal authorities have confirmed 12 infestations in the United States since the first was discovered June 3 in a calf in Zavala County. Most have involved animals in Texas, including cattle, goats and a sheep, with detections extending from South Texas into the Hill Country and Sutton County. One case involving a dog was confirmed in New Mexico.
The female screwworm fly deposits eggs in wounds or natural openings of warm-blooded animals. After hatching, the larvae burrow into living tissue, creating wounds that can grow rapidly and become fatal without treatment. Livestock, wildlife and pets are vulnerable, while human cases are uncommon.
Gov. Greg Abbott has declared a statewide disaster and activated the State Emergency Operations Center at an escalated-response level. Authorities have also established infested zones covering portions of several counties. Warm-blooded animals generally cannot leave those zones without authorization from the Texas Animal Health Commission.
The primary containment tool is the release of millions of sterile male flies. Because female screwworm flies typically mate only once, breeding with sterile males produces no offspring and can gradually collapse the population.
Officials are also expanding traps, inspecting animals, treating infestations and restricting livestock movements.
U.S. Agriculture Secretary Brooke Rollins has expressed confidence that the outbreak can be contained. Texas Agriculture Commissioner Sid Miller, however, has criticized the federal response as too slow and called for additional insecticides and suppression tools.
Officials stress that screwworm does not contaminate meat or threaten the food supply directly. But an uncontrolled outbreak could kill animals, disrupt livestock movement and impose significant costs on ranchers.
Animal owners are being urged to inspect wounds daily and immediately report suspicious larvae. Authorities warn that unreported cases could allow adult flies to emerge and spread the infestation farther across Texas.
Guests:
Richard Peña Raymond is a Texas State Representative, District 42, which encompasses western Webb County and includes the city of Laredo.
Dr. Hector Treviño is the mayor of Laredo.
Dr. Gaylon Wilmeth-Burleson is a veterinarian in Dilley, Frio County.
Breyana Segura is the chief staff writer for the Frio-Nueces Current, local newspaper serving Frio, Nueces and surrounding counties in South Texas.
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