06/17/2026
The State of Wyoming has been made aware of the New World screwworm (NWS) affecting Texas and New Mexico at this time.
No cases have been reported in Wyoming.
NWS is a serious pest that affects livestock, pets, wildlife, and, less commonly, people and birds. Adult screwworm flies are about the size of a common housefly or slightly larger. Their larvae feed on the living tissue of warm-blooded animals.
Please visit https://Screwworm.gov for further information.
Given that it can infest wildlife, G&F is asking outfitters to be even more vigilant about inspecting their livestock before heading into the back country.
โWyoming State Board of Outfitters
Learn how the U.S. Government prevents New World screwworm and what to know about risks, surveillance, sterile-fly control, travel, and more.