For most hunters in far West Texas, the work after the shot follows a familiar order: find the animal, take a breath, roll up the sleeves and get the knife out. This season, Texas Parks and Wildlife Department officials want one step added before any of that, a slow and deliberate look at the animal itself. The reason is a cow elk taken in Pecos County that turned out to be carrying New World screwworm, a parasite most American sportsmen had only read about in history books until recently.
TPWD said it received confirmation on Oct. 21 that New World screwworm, often shortened to NWS, had been detected in a hunter-harvested female elk in Pecos County. A sample from the animal was collected and then identified and confirmed as NWS at the ARS Knipling-Bushland U.S. Livestock Insects Research Laboratory in Kerrville, the federal research facility that carries the names of the two scientists most associated with the pest's defeat in the twentieth century.
The agency framed the find as proof that people in the field matter. In its release, TPWD said the detection highlights the critical role that hunters, landowners, outdoor enthusiasts and wildlife professionals play in spotting the parasite and managing its spread.
"We encourage all hunters and landowners to be vigilant for signs of New World screwworm while they are out in the field this season," said Alan Cain, Wildlife Division Director. "The partnership between TPWD biologists and local hunters and landowners expedited the identification and confirmation of this new detection."
A Cow Elk, a Federal Lab and a Map That Is About to Change
The elk detection does not stand alone. According to TPWD, the Texas Animal Health Commission (TAHC) will modify a previously established infested zone in response, and the U.S. Department of Agriculture and TPWD are conducting additional wildlife surveillance in the area. In plain terms, the boundaries that govern animal movement in that part of the state are being redrawn, and biologists are actively looking for more cases in wild animals nearby.
Pecos County was already part of the story before this fall. Earlier in 2026, reporting from West Texas outlets described a TAHC emergency order covering Crockett, Pecos and Terrell counties after a detection in a dog in Pecos County at the end of June, with movement restrictions applied to livestock, exotic livestock and fowl. TPWD's own background material on the outbreak notes that the first Texas case this year was found in a calf in early June. The elk confirmation is significant because it puts the parasite in a free-ranging big-game animal taken by a hunter, which is exactly the scenario wildlife managers have been asking sportsmen to watch for.
For a hunter, the practical meaning is straightforward. Anyone hunting in or near the affected region of the Trans-Pecos this fall should assume that the parasite could be present, should know what infestation looks like and should know the rules about what can and cannot leave the property where an animal was killed.
Why This Fly Is Not Like the Others
Hunters see maggots on carcasses every season, and most of them are harmless scavengers doing what nature intends. The New World screwworm is a different animal entirely. According to TPWD's New World Screwworm Guide for Hunters and Landowners, the adult flies (Cochliomyia hominivorax) lay eggs in open wounds or in mucous membranes such as the nostrils, eyes, genitalia, newborn navels or mouths of live warm-blooded animals. The eggs hatch into parasitic larvae that feed only on live tissue, while other species of fly larvae prefer dead or rotting tissue.
The name comes from how the larvae behave. TPWD's guide describes them burrowing, or "screwing," into living tissue with sharp mouth hooks, which gives them a screw-like appearance. Infested wounds become infected quickly, and the agency warns that infested animals will die if left untreated. That is why the pest has such a fearsome reputation among ranchers: a small scratch from barbed wire, a fight between bucks or a tick bite can become a fatal wound in a matter of days.
For the sportsman, that biology carries two lessons. First, a living animal that looks sick, isolated or unusually distressed may be telling you something. Second, a harvested animal can carry live larvae that are still capable of completing their life cycle if the carcass is handled carelessly, which is why TPWD's disposal guidance is so specific.
Reading the Animal Before the Knife Comes Out
TPWD's core request this season is simple: inspect the harvest before field dressing or moving the carcass. With hunting season getting underway across Texas, the agency is encouraging every hunter to make that inspection a habit, not just those in counties with known detections.
Signs in a Live Animal
While glassing or still-hunting, TPWD says hunters should watch for animals that may be showing signs of infestation. The agency's list includes irritated or depressed behavior, loss of appetite, head shaking, the smell of decaying flesh, the presence of fly larvae (maggots) in wounds, and isolation from other animals or people. None of those signs alone proves an animal has screwworm, but an elk or deer that hangs apart from the herd, shakes its head repeatedly or carries an obvious open wound deserves a closer look through the binoculars and a note in the hunting journal.
The Post-Shot Inspection
Once an animal is down, TPWD asks hunters to check the eyes, ears, nose, mouth, genitalia and any mucous membranes. The agency also recommends running your hands along the body of the animal and checking the feet and between the toes, looking for any wounds that might have a foul smell or maggots. Experienced hunters already do some version of this when they look for an old wound or a broadhead from a previous season; the difference now is doing it carefully and in good light before the carcass is opened up or loaded into a truck.
A pair of disposable gloves and a small flashlight make the job easier, especially at last light. TPWD has also published a video on how to inspect harvested game for NWS, and the agency's hunter and landowner guide lays out the full process.
If You Find Larvae: TPWD's Carcass Rules
The stakes of a suspected infestation are not just about one animal. TPWD's guide states that ensuring no viable NWS larvae are left on or in a carcass is of paramount importance to stop the parasite's life cycle. Its guidance for hunters who suspect an infested animal is detailed, and it is worth knowing before heading out rather than reading it on a phone in the dark.
First Steps in the Field
According to the guide, a hunter who suspects screwworm should report the case to the local TPWD wildlife biologist. The carcass should be placed on a tarp, plastic sheeting or a hard surface to keep larvae from migrating into the soil. The hunter should then remove all larvae from the wound or cut out the entire affected area.
Removed larvae should go into a tightly sealed container and be completely submerged in 70 percent isopropyl alcohol, and TPWD says those samples should be handed off quickly to the local wildlife biologist. Any infested parts that are cut away should be double-bagged and kept in a freezer until frozen solid, after which they may be disposed of. It is worth tossing a small bottle of rubbing alcohol, a screw-top vial and a few heavy contractor bags into the truck kit for the season.
What Happens to the Carcass
TPWD's guide says carcasses of animals suspected of having or infested with NWS should be burned, completely frozen, or buried to a depth of 4 feet or more with tightly compacted soil on the premises of harvest, so larvae cannot travel through the soil. The agency is explicit that infested carcasses should not be removed from the property of harvest, and that hunters should avoid leaving a carcass with unmitigated larvae on the landscape.
Meat, Mounts and Moving Parts
TPWD does not recommend consuming apparently sick or infested wildlife. If parts of an infested animal are kept, the guide says no infested animal parts shall be transported outside an infested area, and any non-infested parts should be thoroughly inspected before they leave. For animals taken inside infested areas generally, the agency encourages hunters to debone meat and properly dispose of unused carcass parts, a step that reduces the chance of carrying larvae out in a hide, a skull or a quarter wrapped in a game bag.
That last point affects trophy hunters and anyone who takes a cape to a taxidermist. Before driving a head or a hide out of the region, it pays to inspect it carefully and to ask the outfitter, landowner or local biologist about the current infested-zone boundaries, which TAHC is in the process of adjusting.
Who to Call, and When
TPWD's message on reporting is blunt: early detection and reporting is critical, and all suspected and confirmed cases of NWS should be reported immediately. The agency has split the reporting lines by animal type.
For a wild animal suspected of having an infestation, hunters should contact their local TPWD wildlife biologist or call 512-389-4505. Suspected cases in livestock and companion animals go to TAHC, either through a region office or the Veterinarian on Call at 1-800-550-8242. TPWD's guide adds that people with concerns about their own health should contact a healthcare provider, and it points to the Texas Department of State Health Services for human-health information. The state's broader resource hub is listed by TPWD as screwworm.texas.gov.
Hunters who photograph a suspicious wound before handling it will make a biologist's job easier. TPWD's guide specifically invites people to share applicable photos or videos when they contact their local biologist.
The Old Enemy Behind the Kerrville Lab's Name
The facility that confirmed the elk sample carries a lot of history. Edward Knipling and Raymond Bushland, the entomologists for whom the Kerrville lab is named, developed the sterile insect technique in the mid-twentieth century: rearing huge numbers of flies, sterilizing them with radiation and releasing them so that wild females mated with sterile males and laid eggs that never hatched. The approach drove the screwworm out of the United States in the decades that followed and then pushed it south through Mexico and Central America, where a biological barrier was maintained for years near Panama.
That success is the reason several generations of American hunters never had to think about the pest. Older ranchers in the Hill Country and the Trans-Pecos remember a time when doctoring screwworm cases was routine work every summer, and when a newborn calf or fawn's navel was a common entry point. The current outbreak, which has moved north from Central America and Mexico in recent years, has brought that history back into the present.
There is also a wildlife precedent. In 2016, an outbreak in the Florida Keys killed a number of endangered Key deer before federal and state officials used sterile fly releases to stamp it out. That episode showed both how quickly the parasite can hit a wild deer population and how effective coordinated response can be once it is detected.
What It Means for a Texas Hunting Season
None of this is a reason to cancel a West Texas hunt. TPWD's message is about vigilance, not avoidance. The agency is relying on the same people who are already in the field glassing ridges and checking game cameras. Its hunter guide notes that regularly reviewing game camera footage, observing wildlife while hunting and inspecting harvested animals are all important surveillance tools, and that field observations from hunters and landowners will be important for early detection.
The guide also lists a few general precautions that apply well beyond Pecos County: keep open wounds on animals and people clean and covered, treat clothing, gear and people with proper repellents, and comply with all state and federal regulations related to animal movement out of infested areas. For a hunter who nicks a hand on a broadhead or gets torn up by catclaw, that first point is worth taking seriously.
For landowners and outfitters, the elk confirmation is a reminder that hunters are a real asset in disease surveillance. A client who checks a harvested animal thoroughly, reports anything odd and follows the carcass rules is helping protect the ranch's livestock, its deer herd and its neighbors. For the hunter, a few extra minutes of inspection and a properly stocked truck kit are a small price for a season that keeps a dangerous parasite from going any further.
Hunters planning a trip to the region can find TPWD's inspection video and its New World Screwworm Guide for Hunters and Landowners through the department's website, and should check with TAHC for the updated infested-zone boundaries before moving any animal, carcass or trophy out of the area.
