The southern border was closed to imports of the animals after screwworm, eradicated in the U.S. for decades, had been moving northward in Mexico.

Imports of livestock from Mexico will resume in phases starting next week after a ban in May at ports of entry because of fear of the spread of New World screwworm, the U.S. Department of Agriculture announced Monday.

Key progress” has been made against the New World screwworm, the U.S. ag secretary says, adding that there has been no northward spread in eight weeks.