Meat producer Alexander & Hornung has widened its recall of pork products over concerns that they may be contaminated with listeria.

The Michigan-based company announced on December 5 that it was recalling 234,391 pounds of its products after it notified the U.S. Department of Agriculture's Food Safety and Inspection Service that product sampling had found Listeria monocytogenes.

Alexander & Hornung is now increasing the recall tenfold to 2,320,774 pounds, covering an expanded list of fully cooked ham and pepperoni products.

The recall includes Alexander & Hornung-branded items such as spiral sliced ham, as well as private label products made for retail customers. These brands include Niman Ranch, Amish Country Fresh Brand, Big Y and Wellshire.

Alexander & Hornung, a business unit of Perdue Premium Meat Company Inc., already recalled 234,391 and has now expanded that to 2,320,774 pounds of fully cooked ham and pepperoni products because of possible Listeria monocytogenes contamination. https://t.co/CgC2bJUj6J

The items being recalled are of different sizes and sell-by dates, but they all carry the establishment number "EST. 10125" inside the U.S. Department of Agriculture mark of inspection.

Alexander & Hornung said in a statement on its website that there had been "no illnesses or complaints associated with the products."

"There is no conclusive evidence" any of the recalled products "were contaminated at the time of shipment," it said, adding: "The voluntary recall is being initiated out of an abundance of caution."

According to the U.S. Centers for Disease Control and Prevention, consuming food contaminated with listeria bacteria can sicken pregnant women, newborns, older adults, and people with weakened immune systems.

Symptoms are usually reported between one and four weeks after eating contaminated food, but can take up to 70 days to show themselves.

The symptoms can include muscle aches, headache, stiff neck, confusion, loss of balance and diarrhea or other gastrointestinal symptoms.

The CDC said it was "rare" for other groups to get sick with listeria, which is recorded in around 1,600 people in the United States every year.

The Food Safety and Inspection Service said people with at-risk products in their refrigerators or freezers should not consume them. The items should be thrown away or returned to the place of purchase for a refund.

Consumers seeking further information are advised to call the company's hotline on 866-866-3703. The phoneline operates from 9 a.m. to 6 p.m. on Monday to Friday.

Alexander & Hornung was founded in Detroit in 1945 and is a unit of Perdue Premium Meat Co., Inc. It has provided a full list of recalled products.

Newsweek has contacted the company for comment.

Concerns about listeria have sparked other recalls this year. In July, Give and Go Prepared Foods Corp issued a voluntary recall for its blueberry, strawberry, banana nut, chocolate and corn muffins and mini-muffins, which are sold at major stores such as Walmart and 7-Eleven.

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