Several pecorino Romano cheese products that were voluntarily recalled in November due to possible listeria contamination have been reclassified by the U.S. Food and Drug Administration to the highest hazard level.

In a Jan. 6 enforcement report, the FDA updated a prior Nov. 21, 2025, voluntary recall from the Ambriola Company to a Class 1 designation, which means the affected cheese products -- which were recalled after routine testing confirmed the presence of listeria, according to the company -- could cause "serious adverse health consequences or death" if consumed.

The recalled products were distributed to retail stores and food distributors nationwide between Nov. 3, 2025, and Nov. 20, 2025. Products were sold under several brand labels, including Ambriola, Locatelli, Member's Mark, Pinna and Boar's Head.

The 20 states where the cheese was distributed include Arizona, California, Colorado, Connecticut, Delaware, Florida, Georgia, Illinois, Indiana, Massachusetts, Maine, New Jersey, New York, Ohio, Oregon, Pennsylvania, Texas, Virginia, Washington and Wisconsin.

Eight pecorino Romano products sold in various sizes were impacted. Four were retail products that could be found in consumers' refrigerator or freezers and another four were larger bags sold by the pound.

See the list of products below, and click here to see the full recall notice with specific expiration dates and lot numbers.

• Locatelli Pecorino Romano Grated 4 and 8-ounce plastic cups with lids

• Boar's Head Grated Pecorino Romano 6-ounce cup with lid

• Member's Mark (private label from Sam's Club) Pecorino Romano 1.5-pound bag

• Locatelli Grated Pecorino Romano, 5 and 10-pound plastic bags

• Ambriola Piccante Grated Pecorino Romano, 5 and 10-pound plastic bags

• Pinna Grated Pecorino Romano, 10-pound plastic bags

• Boar's Head Pecorino Romano Grated, 5-pound plastic bags

While no illnesses have yet been reported, per Ambriola's most recent press release on the recall on Dec. 3, the company has urged any customers who have symptoms of listeria infection to contact a health care provider.

"We take food safety very seriously and immediately alerted stores and distributors to remove the affected products from shelves," Ambriola CEO Phil Marfuggi stated in the release. "We are working closely with the FDA and continuing to test our products and facilities to fully understand the situation."

Ambriola has suspended production and distribution of affected products as it conducts "a thorough review of all sanitation and food safety procedures," the company said.

The company has instructed customers who purchased the recalled products not to consume them and to "either dispose of them or return them to the place of purchase for a full refund."

Affected customers can call Ambriola for more information at (800) 962-8224, Monday through Friday, from 9 a.m. to 4 p.m. ET.

ABC News has reached out to Ambriola for comment on the recall.

What to know about listeria and its symptoms

Listeria is a bacteria that when ingested can cause an infection known as listeriosis, according to the Centers for Disease Control and Prevention.

The condition is most dangerous for pregnant people, newborns, people with weakened immune systems and adults 65 or older, the agency says. For people who are pregnant, being infected by listeria can cause pregnancy loss or premature birth.

According to the CDC, an estimated 1,250 people get listeriosis annually in the U.S. and approximately 172 people die from it.