Deli-sliced meats and cheeses are to blame for a multistate outbreak of Listeria infections involving eight people, one of whom has died. The Centers for Disease Control and Prevention late Wednesday announced a state and federal investigation into the Listeria outbreak is underway.

Both the U.S. Department of Agriculture’s Food Safety and Inspection Service( FSIS) and the U.S. Food and Drug Administration have joined the effort.

Listeria specimens from ill people were collected from Nov. 13, 2016, through March 4, 2019. People confirmed with Listeria monocytogenes infections range in age from 40 to 88 years, with a median age of 57. Thirty-eight percent are female. All eight confirmed patients were hospitalized. Michigan officials reported one patient in their state died.

Epidemiologic and laboratory evidence indicates that deli-sliced meats and cheeses might be contaminated with Listeria monocytogenes and could make people sick, according to the CDC.

In interviews, ill people answered questions about the foods they ate and other exposures in the four weeks before they became ill. Of six patients who have been interviewed by public health officials, five reported eating products sliced at a deli counter, including meats and cheeses. Delis wher ill people shopped served many different brands of products and there is limited information available about the brands’ ill people bought.

FSIS and FDA evaluated records state inspectors collected from delis wher the ill people ate to determine whether a common meat or cheese product was served at the delis. The analysis of the available documentation could not identify a common product. The FSIS and FDA will continue to assist with the investigation should additional information become available.

The outbreak strain of Listeria monocytogenes has been identified in samples from meat sliced at a deli, and from deli counters in multiple retail locations in New York and Rhode Island. Whole genome sequencing showed that the Listeria strain from these samples is closely related genetically to the Listeria strain from ill people. This result provides more evidence that people in this outbreak got sick from eating deli-sliced products. At this time, the investigation has not identified a common product that was sliced or prepared in the delis.

CDC’s advice to consumers and retailers
People who are at higher risk for Listeria infection should avoid eating lunch meats, cold cuts, or other deli meats unless they are heated to an internal temperature of 165 degrees F just before serving.

If you develop symptoms of a Listeria infection after eating deli-sliced products, contact a healthcare provider and tell them you ate deli-sliced products. This is especially important if you are pregnant, age 65 or older, or have a weakened immune system.

If you have eaten deli-sliced products and do not have any symptoms of a Listeria infection, most experts believe that tests or treatment are not needed, even for people who have a higher chance of Listeria infection.

Listeria bacteria can survive at very low temperatures and can spread easily to other foods and surfaces. Consumers should clean refrigerators, kitchen countertops, utensils, and other surfaces that touch deli-sliced products.

You can take steps to prevent Listeria infection:

Don’t let juice from lunch meat and hot dog packages get on other foods, utensils, and food preparation surfaces.

Wash hands after handling deli meats, lunch meats, deli cheeses, and hot dogs.

Store opened packages of meat sliced at a local deli no longer than 3 to 5 days in the refrigerator.

Retailers should clean and sanitize deli slicers frequently and other areas wher deli products are prepared, stored or served. Staff should follow the manufacturer’s recommendations for sanitizer strength and application to ensure they is effective.

Regularly clean food contact surfaces, equipment, and utensils in direct contact with deli products, such as cutting boards, tables, cheese slicers, and knives.

Make sure food contact surfaces, such as cutting boards, are smooth, sealed, non-porous, and easily cleanable.

The FDA website has printable materials and more information about sanitizing commercial deli slicersExternal.

CDC will updat the advice to consumers and retailers if more information comes available, such as a supplier or type of deli product linked to illness.