Major U.S. deli supplier Boar's Head was expanding its recall of meat products to an additional 7 million pounds of goods, after one of the company's products was linked to a widespread listeria outbreak tied to sliced deli meats that has sickened more than a dozen New York and New Jersey residents.

The expansion includes 71 products — packaged meat and poultry products sold at retail locations, as well as meats intended for deli slicing — marketed under both the Boar’s Head and Old Country brands, according to the U.S. Department of Agriculture’s Food Safety and Inspection Service. The products were produced between May 10 and July 29, and have "sell-by" dates ranging from July 29 through Oct. 17.

Boar's Head said it was pausing production of "ready-to-eat" products at its facility in Jarratt, Virginia, "out of an abundance of caution" and recommended that consumers throw away or return any of the recalled products. The company also said the USDA told it on Monday evening that its Strassburger Brand Liverwurst was connected to the listeria outbreak. A total 200,000 pounds of that product and nine others made on the same day and production line at the Jarratt facility were voluntarily recalled last Friday.

"On behalf of all of us at Boar’s Head Brand, we want to let our customers and consumers know that we deeply regret that our liverwurst products were found to be adulterated with Listeria monocytogenes," the Florida-based company said on its website. "No words can fully express our sympathies and the sincere and deep hurt we feel for the families that have suffered losses and others who endured illness."

As of Friday, the outbreak had 34 confirmed cases of listeria illness across 13 states, according to the U.S. Centers for Disease Control and Prevention, which is investigating alongside other public health agencies. Those who became ill include 12 New Yorkers and two New Jersey residents, one of whom died. The CDC said a second death linked with the deli meat-related outbreak was reported in Illinois.

"The true number of sick people in this outbreak is likely higher than the number reported, and the outbreak may not be limited to the states with known illnesses," the agency warned. "This is because some people recover without medical care and are not tested for Listeria. In addition, recent illnesses may not yet be reported as it usually takes three to four weeks to determine if a sick person is part of an outbreak."

Symptoms of the infection listeriosis include fever, muscle aches, fatigue and headaches. People who are pregnant, 65 or older, or have weakened immune systems are at higher risk of getting sick, as listeria is more likely to spread from their guts to other parts of their bodies, according to the CDC. Severe listeriosis can cause pregnancy loss, premature birth, life-threatening infections in newborns, hospitalization and occasionally death.

Health officials are advising vulnerable groups to avoid recalled meats and refrain from eating other deli meats sliced at deli counters unless they're first reheated to an internal temperature of 165 degrees or until steaming hot. Officials also recommend that people at higher risk clean any refrigerators, containers and surfaces that might have come into contact with sliced deli meats.

The New York City health department told Gothamist last Friday that it was working to spread the word about the outbreak and make sure the recalled Boar's Head products were removed from stores. The owner of a cafe in SoHo said the company came to take away recalled merchandise, and two deli managers in the neighborhood said they were unaware of the initial recall.