CDC, public health and regulatory officials in several states, and the U.S. Food and Drug Administration (FDA) are collecting different types of data to investigate a multistate outbreak of Listeria monocytogenes infections.

A specific food item has not yet been identified as the source of this outbreak.

Sick people’s samples were collected from July 3, 2018, to March 31, 2023.

Here is an illustration of why it takes so long to figure an outbreak out.

As of April 20, 2023, a total of 18 people infected with the outbreak strain of Listeria have been reported from 15 states – Arkansas 1, California 1, Colorado 1, Illinois 1, Louisiana 1, Michigan 2, Missouri 1, Nebraska 1, New York 1, North Carolina 2, Pennsylvania 1, South Dakota 1, Texas 1, Washington 1 and Wisconsin 2.

Sick people range in age from less than 1 to 96 years, with a median age of 73, and 61% are female. Race or ethnicity information is available for 18 sick people. Two sick people reported Hispanic ethnicity. Of 16 people that did not report Hispanic ethnicity, 15 are White and one is African American/Black. Of 18 people with information available, 17 have been hospitalized. There is one pregnancy-associated illness in a newborn.