As of November 15, 2022, two people infected with the outbreak strain of Listeria have been reported from two states. Sick people’s samples were collected from October 5, 2022, to October 8, 2022.

The two sick people are 30 and 42 years old, and they are both males. Both have been hospitalized, and no deaths have been reported.

Both sick people reported eating enoki mushrooms or eating at restaurants with menu items containing enoki mushrooms.

Public health investigators are using the PulseNet system to identify illnesses that may be part of this outbreak. CDC PulseNet manages a national database of DNA fingerprints of bacteria that cause foodborne illnesses. DNA fingerprinting is performed on bacteria using a method called whole genome sequencing (WGS). WGS showed that bacteria from sick people’s samples are closely related genetically. This suggests that people in this outbreak got sick from the same food.

In November 2021, FDA found Listeria in one sample of enoki mushrooms that they collected at import, as part of the FDA’s strategy to prevent Listeria outbreaks linked to imported enoki mushrooms. These enoki mushrooms were destroyed. The Listeria from this sample is closely related genetically to the Listeria that made the people in this outbreak sick. However, to date, the firm associated with this sample has not been identified as a potential source of enoki mushrooms in this outbreak.

CDC advises people who are pregnant, aged 65 or older, or have a weakened immune system to not eat raw enoki mushrooms. CDC also advises restaurants to not serve raw enoki mushrooms. Cook enoki mushrooms thoroughly to kill any foodborne germs. Currently, FDA has issued three import alerts that include enoki mushrooms.