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June 30, 2025
Texans prepare for possible outbreak of damaging parasite
By Jessica Nohealapa’ahi
The Bandera Prophet
The New World screwworm was eradicated from Texas in 1964, and the entire country in 1966, according to the National Agriculture Library, after a decade of wreaking havoc on livestock and wildlife nationwide, including Bandera County. Recently, the parasite was detected 600-700 miles south of the U.S. border. Though not in Texas yet, officials are taking action in an effort to combat a potential reinfestation.
The New World screwworm is the larvae of the New World screwworm fly (Cochliomyia hominivorax), which burrow, or “screw” into and feed off of the living tissue of warm-blooded animals, “including livestock, wildlife and humans,” according to the Texas A&M AgriLife Extension Service. The wounds can be serious, and sometimes fatal.
Bandera County native Billy Walker recalled the summer of 1962, when his family’s sheep and goats were injured by a small pack of dogs.
“Although none were killed, the survivors quickly contracted screwworms, and their survival rate was dismal,” Walker shared for a collection of rural American first-hand stories in the Bandera Natural History and Art Museum’s satellite Smithsonian Institution exhibit.
“In the 50s and 60s, the screwworm devastated the sheep and goat population,” Pct. 4 Commissioner Jody Rutherford said. “Measures were taken in the U.S. and Mexico to drive flies further south. They are coming back. We need to begin doing something now…before we get inundated.”
Preemptively, Bandera County commissioners this month passed a resolution requesting federal and state support to ward off the New World screwworm. The Texas Animal Health Commission, Texas Parks and Wildlife Department and U.S. Department of Agriculture have also joined the team.
“There was a place in Texas that raised sterile flies, the screwworms bred with them and ended the infestation,” Pct. 3 Jack Moseley said, referencing the Sterile Insect Technique. “I was a kid, but I remember it.”
The USDA on June 18 announced an international collaboration to open a sterile fly dispersal facility in Texas, using sterile flies produced in Mexico. In May, the southern U.S. border was closed to cattle, bison and equine imports, however today the USDA announced ports would reopen in stages possibly next week, beginning in Arizona, followed by New Mexico and Texas.
Ranchers are encouraged to monitor and report any suspected cases or signs of the damaging pest, which include foul-smelling wounds with visible maggots, animals biting or licking wounds, lesions, unusual restlessness or lethargy, irritated or depressed behaviors, loss of appetite, head shaking, isolation from other animals or people.
“We now have exotics, some worth tens of thousands of dollars,” Bandera County Judge Richard Evans said. “Maybe the rich guys will help us out.”
The New World screwworm is the larvae of the New World screwworm fly (Cochliomyia hominivorax), which burrow, or “screw” into and feed off of the living tissue of warm-blooded animals, “including livestock, wildlife and humans,” according to the Texas A&M AgriLife Extension Service. The wounds can be serious, and sometimes fatal.
Bandera County native Billy Walker recalled the summer of 1962, when his family’s sheep and goats were injured by a small pack of dogs.
“Although none were killed, the survivors quickly contracted screwworms, and their survival rate was dismal,” Walker shared for a collection of rural American first-hand stories in the Bandera Natural History and Art Museum’s satellite Smithsonian Institution exhibit.
“In the 50s and 60s, the screwworm devastated the sheep and goat population,” Pct. 4 Commissioner Jody Rutherford said. “Measures were taken in the U.S. and Mexico to drive flies further south. They are coming back. We need to begin doing something now…before we get inundated.”
Preemptively, Bandera County commissioners this month passed a resolution requesting federal and state support to ward off the New World screwworm. The Texas Animal Health Commission, Texas Parks and Wildlife Department and U.S. Department of Agriculture have also joined the team.
“There was a place in Texas that raised sterile flies, the screwworms bred with them and ended the infestation,” Pct. 3 Jack Moseley said, referencing the Sterile Insect Technique. “I was a kid, but I remember it.”
The USDA on June 18 announced an international collaboration to open a sterile fly dispersal facility in Texas, using sterile flies produced in Mexico. In May, the southern U.S. border was closed to cattle, bison and equine imports, however today the USDA announced ports would reopen in stages possibly next week, beginning in Arizona, followed by New Mexico and Texas.
Ranchers are encouraged to monitor and report any suspected cases or signs of the damaging pest, which include foul-smelling wounds with visible maggots, animals biting or licking wounds, lesions, unusual restlessness or lethargy, irritated or depressed behaviors, loss of appetite, head shaking, isolation from other animals or people.
“We now have exotics, some worth tens of thousands of dollars,” Bandera County Judge Richard Evans said. “Maybe the rich guys will help us out.”