New World Screwworm Reaches the US, Deepening Mexico’s Cattle Crisis

Economy · Agriculture

Key Facts

—First US Case in Decades The USDA confirmed the first U.S. detection of New World screwworm in decades on June 3, 2026, in a bovine in Zavala County, Texas, signaling the parasite has spread north.

—Border Remains Mostly Closed The U.S. has kept its border mostly closed to Mexican live cattle since May 2025, disrupting a trade that previously supplied more than 1 million animals annually to U.S. feedlots.

—Massive Financial Losses Ranchers are losing about $1,000 per head, and the state of Chihuahua alone is losing about $500 million a year in opportunity cost, squeezing producers on both sides of the border.