Cases of the New World screwworm in the United States surpassed 10 over the weekend as federal and Texas agencies continue to combat the threat of the parasitic fly to livestock.

Screwworm, a parasitic fly whose flesh-eating larvae feed on living ⁠animals, ⁠re-entered the U.S. Southwest in June for the ⁠first time since the 1970s, posing a threat to the livestock industry as w...

The New World screwworm was a massive problem in U.S. cattle herds for much of the 20th century, killing countless cows and costing the industry hundreds of millions of dollars.