The U.S. Department of Agriculture working to contain an outbreak of the New World screwworm in Texas to prevent the invasive species from spreading to Tennessee livestock and wildlife.
White County Ag Extension Director Scott Swoape said the number of active cases in Texas has already doubled. Swoape said pets and animals can be at serious risk.
“The fly is the problem,” Swoape said. “So the fly actually lays eggs, a mated fly will lay eggs on open, on an open wound. And then those maggots, when that, when that those fly larva or the maggots then, they infest or bury into the living tissue of warm-blooded animals.”
Swoape said the screwworm larvae can affect livestock, pets and wildlife by eating the flesh of the host animal before dropping into the soil to pupate. Swoape said a single female fly can lay up to 3,000 eggs, allowing the population to magnify rapidly in a short period of time.
“It’s not going to affect our food in any way,” Swoape said. “It’s more of an animal welfare concern because it does affect all those species of livestock and wildlife. Especially the livestock, somebody’s tending after them, so they can see those and the pets… you’re going to see that pretty quick. But just for instance, you look at the state of Texas and all the wildlife that’s there in Texas, in some areas it’s going to be real hard to control.”
Swoape said the USDA is releasing approximately four million sterile male flies per week in the affected area to disrupt the mating cycle. Swoape said because the female fly only mates once, mating with a sterile male results in unfertilized eggs that stop the reproductive process.
“If you have an area, an open wound, and say like on a newborn calf, if you have the umbilical cord, that area is an open wound,” Swoape said. “If a fly lands on that and lays eggs, in just a short period of time those eggs are going to turn into larva. That larva is then going to, you know, grow and start eating at that, making that spot bigger and bigger and that’s just going to attract more flies to come lay in that same area.”
Swoape said officials are taking immediate action to limit the interstate transportation of live animals to prevent the screwworm from reaching Tennessee. Swoape said while the risk to humans is very rare, the infestation can cause graphic and severe wounds on animals that require quick identification and treatment.
Swoape said producers should continue to monitor the situation as more cases are expected to be reported.
“It’s an ever-changing issue,” Swoape said. “Just keep aware of what’s going on. And as producers, be vigilant in watching your livestock and stuff. If you have anything that looks abnormal on a wound, you know, that you have any maggots or anything like that that’s on there, please report those to veterinarians immediately. And so we could make sure that we don’t get that spread here in Tennessee.”
