(CBS News) — An outbreak of salmonella infections linked to pig ears purchased as dog treats has expanded to 27 states — including Maryland, Delaware and Virginia —  with 93 people stricken, including 20 hospitalizations, according to federal health officials.

Since Pet Supplies Plus in early June recalled bulk pig ears sold at more than 400 stores in 33 states, another 48 illnesses have been reported, bringing the total count of known infections to 93, the U.S. Centers for Disease Control said late Tuesday. When the retail chain posted its recall, the outbreak involved 45 illnesses in 13 states.

A New Salmonella Outbreak Could Be Caused By Pig Ear Dog Treats, CDC Says

The CDC and the Food and Drug Administration are investigating contaminated pig ears, with evidence pointing to contact with the dog treats as the likely source of the outbreak.

Bulk pig ears were distributed to Pet Supplies Plus stores in Alabama, Arizona, California, Colorado, Connecticut, Delaware, Florida, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Maryland, Massachusetts, Michigan, Minnesota, Missouri, Nebraska, New Hampshire, New Jersey, New York, North Carolina, Ohio, Oklahoma, Pennsylvania, Rhode Island, South Carolina, Tennessee, Texas, Virginia, Wisconsin and West Virginia.

Consumers who purchased bulk pig ears should throw them away. (Anyone with further questions can call (734) 793-6564 Monday through Friday from 9 a.m. to  4 p.m. Eastern time, Pet Supplies said.)

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