Notes from the field: listeriosis associated with stone fruit--United States, 2014

Abstract

On July 19, 2014, a packing company in California (company A) voluntarily recalled certain lots of stone fruits, including whole peaches, nectarines, plums, and pluots, because of concern about contamination with Listeria monocytogenes based on internal company testing. On July 31, the recall was expanded to cover all fruit packed at their facility during June 1-July 17. After the initial recall, clinicians, state and local health departments, CDC, and the Food and Drug Administration (FDA) received many inquiries about listeriosis from concerned consumers, many of whom had received automated telephone calls informing them that they had purchased recalled fruit. During July 19-31, the CDC Listeria website received >500,000 page views, more than seven times the views received during the previous 52 weeks. However, no molecular information from L. monocytogenes isolates was available to assess whether human illnesses might be linked to these products.

FIGURE

Phylogenetic tree by whole-genome multilocus sequence typing (wgMLST) of Listeria monocytogenes isolates from patients in four states and from recalled nectarines and peaches with indistinguishable pulsed–field gel electrophoresis patterns — United States, 2014* * By wgMLST, the Massachusetts patient isolate differed from six closely related nectarine isolates by ≤7 alleles, and the Minnesota patient isolate differed from three closely related peach isolates by ≤5 alleles out of >5,800 loci analyzed in BioNumerics 7.5 wgMLST analysis pipeline. The Illinois and South Carolina patient isolates differed from the most closely related stone fruit isolate by 47 and 69 alleles, respectively.