LA MARQUE — A parasite that was eradicated from the United States decades ago is once again raising concerns among animal health officials, but experts say there is no reason for panic.
KGTX 7 recently spoke with Galveston County Extension Agent Brock Sanford about the New World screwworm, a fly whose larvae, commonly known as maggots, infest open wounds on animals and feed on living tissue. If left untreated, infestations can cause severe injury and even death.
“The screwworm is a fly that drops its larvae or maggots on open wounds of an animal,” Sanford explained. “That could be anything from a cut that an animal gets on a fence to animals giving birth and screwworm dropping eggs on their umbilical cords.”
According to Texas A&M AgriLife Extension, the United States successfully eliminated the pest in the 1960s using a process known as the sterile insect technique.
Officials say the threat is not limited to cattle. Companion animals, wildlife, and other livestock can also become infected if flies deposit larvae into open wounds.
Sanford encouraged animal owners to regularly inspect their animals and watch for signs of infestation.
“Signs can be anything from a really bad odor to animals acting depressed,” he said. “We just want to be vigilant and check all of our animals. If you see something going on, report it. Talk to your veterinarian, your county extension agent, or the Texas Animal Health Commission.”
One challenge facing animal owners is identifying the pest. Sanford said adult screwworm flies closely resemble many other fly species, making visual identification difficult.
“The best way to do it is based on the maggot, based on the larvae that the fly drops in an open wound,” Sanford said. “That is the easiest and most efficient way to identify the New World screwworm.”
While concern has grown across Texas, Sanford emphasized that state and federal agencies are actively working to contain the threat and have successfully defeated the pest before.
“Back in the 1960s, we eradicated screwworm through a technique called the sterile insect technique,” Sanford said. “We produce sterile male flies. A screwworm fly will only reproduce once in her lifetime. If she reproduces with a sterile male, we practically erase the population and get rid of it.”
Sanford said reports and discussions on social media have led to increased concern among some residents, but he believes the situation remains manageable.
“Right now we’re seeing a lot of panic in Galveston County, and that’s something we want to avoid,” Sanford said. “All of our state agencies are working diligently down in South Texas to control this and get it under control using that sterile insect technique. We have eradicated this before, and I believe we can do it again.”
He added, “I don’t want people to panic. This is not the end of times right now.”
Animal owners seeking additional information can contact Texas A&M AgriLife Extension, the Texas Animal Health Commission, the Texas Department of Agriculture, or the Texas Parks and Wildlife Department.
