New Mexico reports 2 more New World screwworm cases
Oct 16, 2026 | 7:43 am ET
Description
The New Mexico Department of Agriculture on Oct. 15, 2026, reported the state's third and fourth cases of New World screwworm (pictured above) in Grant County. (Image via Texas A&M)
The New Mexico Department of Agriculture on Thursday reported two more New World screwworm cases in the state, both in Grant County, inflicting a horse and a calf.
“We are working closely with our state and federal partners to investigate these cases, increase surveillance and monitor for additional infestations,” State Veterinarian Dr. Samantha Holeck with the New Mexico Livestock Board said in a statement.
The cases mark the third and fourth for the state, which in September expanded surveillance for the pest following the detection of the second case in a horse, also in Grant County. New Mexico reported its first case in June — in a Lea County dog — just days after the first U.S. incursion of the devastating parasitic fly in a south Texas calf.
Named for the maggot’s behavior of feeding on live tissue, the New World screwworm Thas advanced rapidly through Mexico after being mainly contained in Central America for several decades. The state launched a one-stop website in mid-May to track cases.
A Thursday news release says state and federal officials continue to expand surveillance and fly-trapping to identify possible additional cases, with a minimum 12.4-mile radius infested zone established around each animal’s location, and the most northern zones combined into one.
“We appreciate the continued cooperation of livestock producers, veterinarians and animal owners as we respond to these additional cases,” New Mexico Secretary of Agriculture Jeff Witte said in a statement. “Early detection and prompt reporting are critical to limiting the spread of this pest. We encourage everyone to remain vigilant and work closely with animal health officials.”
Officials encouraged animal owners to monitor them for: un-healing wounds, wounds with maggots and other abnormal signs of injury and to contact the Livestock Board if they suspect the presence of New World screwworm.
Santa Fe, NM
