The deadly screw worm fly invades the United States, causing live cattle futures to plunge at market open.

⑴ Chicago Mercantile Exchange live cattle futures opened sharply lower on Thursday, as the U.S. confirmed a case of New World screwworm infection. The larvae of this parasite feed on the host’s living tissue, leading traders to worry that consumers will reduce beef consumption.⑵ The U.S. Department of Agriculture confirmed on Wednesday night that screwworm was detected in a calf in Texas; over the past year, this pest has moved north from Mexico. After the sharp drop at the open, futures prices subsequently rebounded.