Screwworm infection reported in Texas ranch horse as animal-movement restrictions continue
A ranch horse in Presidio County has reportedly contracted New World screwworm, as Texas maintains animal-movement restrictions in designated infested zones.
In short
- A ranch horse in Presidio County has reportedly contracted New World screwworm, as Texas maintains animal-movement restrictions in designated infested zones.
A working ranch horse in Presidio County, Texas, has been infected with New World screwworm, according to a September 10, 2026 equestrian-sector statement cited by The Guardian. The newspaper described it as the first US equine case in the current outbreak.
The parasite was found on the horse’s hind limb. The report did not specify the date of diagnosis. Screwworm larvae infest wounds and can cause serious injury to animals, making the detection a concern for horse owners as well as livestock producers.
Texas has imposed animal-movement restrictions in designated infested zones. The Texas Animal Health Commission’s official outbreak page lists affected areas in parts of Presidio and Jeff Davis counties and identifies a September 9, 2026 order covering those counties. The restrictions apply to designated zones, rather than automatically to every location in a listed county.
The outbreak follows the parasite’s return to the United States earlier in 2026. US agricultural authorities confirmed a detection in a bovine in Zavala County, Texas, on June 3, 2026. Federal response measures include surveillance and sterile-fly releases intended to suppress reproduction.
