State and federal officials are working to stop the spread of the New World screwworm while veterinarians are monitoring animals for signs of infestation, treating sick animals, and helping contain further outbreaks.
Dr. Lori Teller, executive director of the Texas Veterinary Medical Association, says preventing the spread remains one of the state’s most urgent animal-health and economic priorities.
The New World screwworm is a pest that threatens livestock, wildlife, pets, and even humans. Teller says that the screwworm is “not actually a worm. It’s a fly larva or maggot,” and unlike ordinary maggots, it feeds on living tissue.
The adult fly seeks out wounds and lays eggs, and the larvae “start eating the flesh and digging pretty deep.” Animals can develop painful infections and, if untreated, may die.
Teller says the pest never actually disappeared. After being pushed south of the Darién Gap decades ago, populations remained largely contained through the release of sterile flies. That system began to fail when the fly population expanded several years ago. “For whatever reason, about three years ago, the fly population just boomed,” she says. “The sterile flies weren’t enough to contain it.”
In June, after months of warnings, the screwworm broke across the Mexico-Texas border, prompting a significant response by local, state, and federal officials.
Containment efforts now depend heavily on international cooperation and containment. Teller points to work involving the U.S. Department of Agriculture, Texas officials, Mexico, and Panama.
New sterile-fly production facilities are being developed, including one planned for Texas. “The U.S. needs to work with Mexico and Panama,” she says, adding that officials are studying how to increase production and improve efficiency.
Failing to contain the pest could have major consequences for Texas agriculture, according to Teller. “The longer it takes us to contain and eradicate the problem, the greater risk to our agricultural industry,” she says.
Livestock losses could affect producers and consumers alike, especially as cattle numbers are already lower than normal. Still, she says that food safety is not at risk. “The food we’re eating is safe,” she says, noting that the screwworm infects live animals and, if infected, animals can be treated and recover before entering the food supply.
Texas has reported a small number of confirmed cases so far, but Teller says that can change rapidly. “It could go quickly,” she says, noting that cases remain active south of the border and that flies can travel significant distances.
She encourages animal owners to seek veterinary care immediately if they notice wounds containing maggots. “If you see a wound, see something suspicious, call your veterinarian,” she says.
The discussion naturally turned to veterinary workforce shortages, particularly in rural communities. Teller says the issue mirrors shortages affecting other sectors of the Texas economy, including doctors, nurses, and other professionals.
Rural practice often presents economic and lifestyle challenges, especially for graduates carrying substantial student debt. “Veterinary students can graduate with upwards of $200,000 of student debt,” she says.
With the real risk of a major spread of the screwworm, the consequences of the lack of rural veterinarians is being felt in real time.