The Texas Animal Health Commission continues to sound the alarm after New World Screwworm was confirmed about 90 miles from the Texas border. TAHC Deputy Executive Director and Assistant State Veterinarian, Dr. T.R. Lansford, says this should be treated as an immediate concern, but not a reason to panic.
“To coin a phrase from one of my colleagues in Virginia, the best thing we can put on animals for New World screw worms is eyes, and so certainly, it’s going to take all of us being very diligent in performing inspections. There are inspections of our animals, just to make sure that we’re finding any potential infestation early so we can treat it and break that life cycle of the pest, or find it a wound early so that we can treat it and prevent infestation.”
He says the fly’s life cycle is about 21 days, which is why timing and early detection matter.
“The fly can move up to about 12 miles on its own during its life span. But typically, these flies are kind of lazy. They don’t really move very much. So, what most of the movement of this pest is a result of, or comes from, is from the movement of infested animals. I think 90-plus percent of the northward movement of the parasite, the New World screw worms in Mexico, has been attributed to cattle movements at this point.”
He added that predicting how far or fast the pest could spread remains difficult.
“There are a lot of factors that influence that. And so certainly, you think about some of the environmental conditions. Weather plays into this suitable habitat, weather patterns, all of those things certainly factor into any prediction. But the other things that go into that consideration include things like efficacy of mitigation strategies, and so start thinking about movement controls of infested livestock to make sure that we’re not moving that infestation by people, movements of animals, efficacy of treatment protocols, and compliance with those protocols as part of a mitigation strategy, and strategic sterile flight dispersal factors into that as well.”
The U.S. has a sterile fly dispersal facility in Edinburg, Texas, but it doesn’t have its own full production facility online yet. It is still relying heavily on facilities in Panama and Mexico, including one expected to come online this summer. A larger sterile fly facility is under construction in South Texas, but it won’t be fully operational until next year.