A horse in Grant County, New Mexico has been confirmed infected with New World screwworm, just days before the state was scheduled to resume livestock imports from Mexico.
The case marks the second confirmed screwworm infection in New Mexico since the flesh-eating parasite entered the United States in June from Mexico.
The infected horse was located in Grant County, near the Mexican border, according to the Department of Agriculture.
The confirmation came shortly after Agriculture Secretary Brooke Rollins announced that the USDA was preparing to reopen the Santa Teresa port of entry to livestock from Mexico on September 24.
According to the New Mexico Department of Agriculture, the horse’s infection had not yet been confirmed at the time Rollins made her announcement at a news conference in Santa Teresa on Thursday.
The Trump administration halted livestock imports along the southern border last year in an effort to curb the spread of New World screwworm across the United States.
That halt helped tighten U.S. cattle supplies and pushed beef prices to record highs for American consumers, adding pressure to household budgets already strained by broader inflation.
Trade partially resumed last month at an Arizona port as part of a phased reopening plan, signaling cautious optimism before this latest case emerged.
Last week, the first U.S. horse to be infested with screwworm was detected in southern Texas near the Mexican border, raising alarm among livestock officials.
Reuters has reported on growing concerns that smuggled animals, including horses, could be serving as possible hosts for the parasite as it spreads northward.
The USDA has tracked 50 confirmed cases of screwworm in the United States since the first outbreak report occurred on June 3.
As of Thursday, only three of those cases remained active, according to the department’s online dashboard, including the horses in New Mexico and Texas and a dog in Texas.
Officials said they were investigating how the horse in New Mexico became infested, as the source of transmission had not been immediately determined.
New World screwworm infestations occur when fly larvae enter an open wound and feed on the living tissue of warm-blooded animals, and the parasite can kill animals if left untreated.
A previous screwworm outbreak killed thousands of animals across the United States before the pest was declared eradicated in the 1960s, making this resurgence a serious concern for ranchers and federal officials alike.
