A multi-year outbreak of Listeria infections traced to peaches, nectarines, and plums has been declared over by the Centers for Disease Control and Prevention. In its final update, the CDC reported that the seven-state outbreak had sickened 11 people and killed one. One of the patients was pregnant and went into pre-term labor.

All of the patients except one were hospitalized. The CDC says many more people were likely sickened in the outbreak but were not reported because they did not seek medical attention or were not tested explicitly for Listeria.

Analysis showed that people in this outbreak were 18 times more likely to eat peaches, nectarines, or plums than sick people not in this outbreak. Sick people’s samples were collected from Aug. 22, 2018, to Aug. 16, 2023.

“On Oct. 23, 2023, the FDA collected a sample of HMC Farms peaches for testing and found Listeria. On Nov. 6, 2023, whole genome sequencing showed that the Listeria in the peaches were closely related to bacteria from sick people. This means that people likely got sick from eating those peaches,” according to the CDC’s final outbreak report.

On November 17, 2023, HMC Farms recalled whole peaches, plums, and nectarines sold in stores between May 1 and November 15 in 2022 and 2023.

This outbreak is an example of how whole genome sequencing can identify outbreak patients separated by long periods. Using the technique, investigators can match new cases with previous ones by comparing samples in a database. Then, finding a match between contaminated food and a patient sample reveals the source of an outbreak.

FDA weighs in on end of the outbreak
The case count by state was: California (3), Colorado (1), Florida (3), Illinois (1), Kansas (1), Michigan (1), and Ohio (1). The patient age range was from 30 to 80 years. Illness onset dates ranged from August 22, 2018 to August 16, 2023. Of ten people who gave information to public health investigators, all were hospitalized. One death was reported from California, and one person suffered preterm labor.

For more information: foodsafetynews.com