Outbreak appears to have begun in 2016.

As of March 9, 2020, 36 people infected with the outbreak strain of Listeria monocytogenes have been reported from 17 states. Arizona 2, California 9, Florida 2, Hawaii 3, Indiana 1, Kentucky 1, Maryland 2, Massachusetts 2, Michigan 1, Missouri 1, Nevada 1, New Jersey 1, New York 4, North Carolina 1, Rhode Island 1, Tennessee 1, Virginia 3.

Four deaths have been reported from California, Hawaii, and New Jersey. Six cases are pregnancy-associated and two resulted in fetal loss.

Listeria samples from ill people were collected from November 23, 2016 to December 13, 2019. Ill people range in age from less than 1 to 97 years, with a median age of 67. Fifty-eight percent of ill people are female. Of 32 ill people with information available, 30 hospitalizations have been reported.

Epidemiologic and laboratory evidence indicates that enoki mushrooms labeled as “Product of Korea” are the likely source of this outbreak.

State and local public health officials interviewed ill people about the foods they ate in the month before they became ill. Twelve out of 22 (55%) reported eating mushrooms, including enoki, portobello, white, button, cremini, wood ear, maitake, and oyster.

Michigan Department of Agriculture and Rural Development collected mushrooms for testing from a grocery store where an ill person purchased enoki mushrooms. Two samples of enoki mushrooms yielded the outbreak strain of Listeria monocytogenes. These mushrooms are labeled as “Product of Korea” and were distributed by Sun Hong Foods, Inc. Additional product testing is ongoing in California.

On March 9, 2020, Sun Hong Foods, Inc. recalled enoki mushrooms (UPC 7 426852 625810) labeled as “Product of Korea”. Consumers, food service operators, and retailers should not eat, serve, or sell recalled enoki mushrooms. Enoki mushrooms distributed by Sun Hong Foods, Inc. do not account for all illnesses in this outbreak. FDA is working to identify the source of the enoki mushrooms distributed by Sun Hong Foods, Inc. and determine if other distributors received the same enoki mushrooms.

CDC is concerned that enoki mushrooms labeled as “Product of Korea” may be contaminated with Listeria monocytogenes and are advising people at higher risk – pregnant women, adults ages 65 years or older, and people with weakened immune systems – to avoid eating any enoki mushrooms labeled as “Product of Korea”, until investigators determine the source of contamination and if additional products are linked to illness.