New World screwworm cases confirmed in wildlife in Texas, beef cow in New Mexico

The elk was located on a game ranch and was reported after being harvested by a hunter, the USDA said in a statement.

The Texas Animal Health Commission will modify a previously established infested zone, and the USDA and the Texas Parks and Wildlife Department are conducting additional wildlife surveillance in the area, the USDA said.

The New Mexico Department of Agriculture said later that animal health officials confirmed a case of New World screwworm in a beef cow in the state's Otero County.

New Mexico authorities said state and federal officials were continuing to expand surveillance and fly-trapping around affected locations to identify any additional cases and determine whether the pest had spread beyond the affected animals.

Officials have established a minimum 12.4-mile (20 km) radius infested zone around the affected animal's location, the New Mexico Department of Agriculture said. 

Within this zone, animals must be inspected and, if necessary, treated before moving within or out of the area, state authorities added.

Eradicated from the US decades ago, the pest has surged north from Central America through Mexico, prompting Washington to impose a more than year-long ban on Mexican cattle imports.

The US halted livestock imports from Mexico last year to keep out screwworm but resumed trade in August at an Arizona port as part of a phased reopening plan.

The halt tightened US cattle supplies, contributing to a rise in beef prices to record highs for American consumers.

(Reporting by Kanishka Singh in Washington; Editing by Matthew Lewis, Christopher Cushing and Lincoln Feast.)