The U.S. has again ceased livestock imports from Mexico related to the presence of the parasitic New World screwworm fly closer to the border.

New cases of screwworms on July 8 in Veracruz, Mexico has caused the U.S. to close southern borders to livestock imports.

The U.S. has shut its southern border to livestock imports again after a flesh-eating parasite was found further north in Mexico than previously reported, raising alarm among American agriculture officials.