A virus that kills young pigs is roiling the U.S. pork industry, boosting prices in the $9 billion hog-futures market and threatening to create more pain for food shoppers.

The disease, which has spread to farms in 22 states, is cutting into pork supplies and prompting some traders and investors to wager that hog prices could set records this year. Lean-hog futures rose to a seven-week high a week ago and are up 6% since mid-December.