SHERMAN, Texas (KXII) – New World screwworm cases have been confirmed in southern Texas, prompting concerns among ranchers and pet owners as officials work to contain the parasite before it spreads further north.
There are 11 confirmed cases in Texas and one case has also been confirmed in New Mexico.
“That’s just the ones they’ve located. You get some wildlife that may be further in, they just haven’t been able to detect it,” said Ben Wible, local farmer.
What makes screwworm dangerous
Screwworm does not need a large opening to infect an animal. The parasite can enter through a small cut, scratch or bite. The larvae then feed on live flesh, leaving animals severely injured and sometimes dead.
“It’s white or cream colored, oh, maybe an inch long,” Wible said, describing what the larvae look like to the naked eye.
Wible said he remembers seeing screwworm firsthand as a child on his own pet.
“We were petting him and then you can actually see where the screwworm was in there,” he said.
Containment efforts underway
Texas and the United States are ramping up production of sterile screwworms as the primary defense against the parasite’s spread.
“Texas and the United States is ramping up that sterile screwworm operation,” Wible said. “And that’ll, that’s our only real defense to stop them.”
Officials are working to increase production from 1 million sterile flies per week to 4 million per week. The sterile flies mate with wild screwworms, preventing reproduction.
Economic impact
If the outbreak spreads north, it could affect ranchers economically. Ranches with confirmed cases could face quarantine, preventing the sale of cattle until herds are proven clean.
“If you had it come up on your ranch here, you might have your ranch quarantined until, not be able to move them off of it to sell them for a little while until they were proven, you know, clean,” Wible said.
The outbreak could also impact meat prices and create additional costs for ranchers who may need to treat animals before shipping.
“It can raise the price of meat,” Wible said. “And it’s just, it hurts the economy if you have that in there.”
Texas has launched a free online training to help residents identify screwworm infestations. Click here to download the course.
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