First U.S. Horse Case of Screwworm Confirmed in Texas, Raising Economic Concerns

Federal data has confirmed the first case of New World screwworm in a U.S. horse, an alarming development for the nation's livestock and equine industries. The U.S. Department of Agriculture (USDA) reported the infection by the flesh-eating parasite was confirmed on Wednesday in a working ranch horse in Presidio County, Texas, near the border with Mexico.

State Imposes Quarantine

In response to the detection, the Texas Animal Health Commission issued an immediate order banning the movement of all warm-blooded animals out of a designated "infested" zone. This quarantine area covers parts of Presidio and Jeff Davis counties.

The U.S. Equestrian Federation specified that the infestation was located in the hind limb of the horse. The organization urged owners to be vigilant, stating, "We encourage every horse owner to help protect their horses and the broader equine community by practicing good wound care, fly control, and biosecurity."

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Economic Risks and Background

The re-emergence of screwworm, which follows months of infestations in U.S. cattle, poses a significant economic threat. Experts estimate a widespread outbreak in Texas alone could cost the state's economy up to $1.8 billion. The pest was previously declared eradicated in the United States in the 1960s after an earlier outbreak killed thousands of animals.

While the USDA and Texas authorities have not commented on the origin of this specific case, Reuters previously reported on concerns that smuggled animals, including horses, could serve as hosts for the parasite. The detection in an equine host escalates concerns about the pest's spread beyond the cattle population.