Media Contacts: TAHC Communications
public_info@tahc.texas.gov, 512.719.0750
For Immediate Release
June 3, 2026
AUSTIN, TX – On June 3, 2026, the Texas Animal Health Commission (TAHC) received confirmation of a detection of New World screwworm (NWS) in Zavala County, Texas. A sample collected from a three-week-old calf with an umbilical lesion was identified and confirmed as NWS by the National Veterinary Services Laboratory (NVSL) in Ames, Iowa. There are currently no further confirmed detections in animals in Texas.
This is the first detection of NWS in Texas since northward progression from Central America was observed in 2023. The TAHC is working closely with USDA and other state officials in a joint incident response. An infested zone has been established in the area, and animal movement restrictions are in effect to prevent further spread of the pest. The agency is working in coordination with the USDA to expand fly trapping and surveillance efforts to identify any additional flies in the area and investigate potential suspect cases in animals. Epidemiological efforts are underway to learn more about this case and prevent spread of the pest.
According to the USDA, the U.S. food supply is safe. USDA’s Food Safety and Inspection Service (FSIS) ensures that the nation’s commercial supply of meat, poultry, and egg products is safe and properly labeled. NWS do not infest meat, fruits, vegetables, or other food sources.
NWS are larvae or maggots of the NWS fly (Cochliomyia hominivorax), that cause the painful condition NWS myiasis. NWS flies lay eggs in open wounds or orifices of live tissue. These eggs hatch into dangerous parasitic larvae, or maggots, which burrow or “screw” into flesh with sharp mouth hooks. NWS primarily infest livestock, but can also affect any warm-blooded animal, including wildlife, pets, humans, and birds.
“TAHC has been actively preparing for a resurgence of NWS for over two years,” said Dr. Bud Dinges, TAHC state veterinarian and executive director. “We are putting these preparations into action, and we encourage all animal owners and caretakers to continue to remain vigilant for the presence of larvae in animal wounds and immediately report any suspicions.”
Targeted releases of sterile NWS flies are being expedited to eliminate any reproducing populations in the area associated with the detection. When combined with enhanced surveillance, movement restrictions, prompt treatment of wounds, and education and outreach efforts, the sterile insect technique is a proven and effective tool for controlling and eradicating this pest.
In addition to frequently monitoring animals, producers should implement enhanced management practices including keeping open wounds clean and covered. Animals infested with NWS should be immediately treated with an appropriate method under the direction of a veterinarian. If you suspect NWS in your livestock or domestic animals, contact the TAHC immediately and do not move your animals. A representative will advise you on current collection protocols for submitting suspicious maggots. Contact the Texas Parks and Wildlife Department (TPWD) for wildlife infestation information and the Texas Department of State Health Services (DSHS) for human infestation information.
Learn more about New World screwworm at screwworm.gov and get current Texas updates and resources at https://www.tahc.texas.gov/emergency/nws.html.
###
The Texas Animal Health Commission (TAHC) was established in 1893 as the Livestock Sanitary Commission and charged with protecting the state’s domestic animals “from all contagious or infectious diseases of a malignant character.” TAHC remains true to this charge while evolving with the times to protect the health and marketability of all Texas livestock and poultry. Learn more about the TAHC by visiting www.tahc.texas.gov.
