Can avocados be a source of Listeria monocytogenes Infections?

CDC researches published (J Food Prot (2021) 84 (7): 1122–1126) a study intended to determine if avocados have been a source of listeriosis. The team conducted a retrospective review of epidemiological data for clinical isolates that were genetically related to isolates from avocados. While to date, avocados have not been identified as the source of any outbreaks of L. monocytogenes infections in the United States, can they be a source of infection. Using a national database, they identified clusters containing clinical and at least one avocado isolate. Clusters were selected based upon isolation dates, cluster and composition size, and available food history data.  For each cluster, they assessed (i) whether avocado consumption was higher among case-patients in the cluster than among those with sporadic illnesses and (ii) whether the only food isolates within the cluster were from avocados. If both conditions were met, the link was considered “likely,” if one condition was met, the link was considered “possible,” and if neither condition was met, evidence was “limited.” Two clusters were classified as having “limited” evidence for a link to avocados, two as “possible,” and one as “likely.”  For the cluster considered “likely,” avocado consumption was significantly higher among case patients than sporadic illnesses. The study suggests that avocados could be a source of listeriosis in the United States.  @ https://meridian.allenpress.com/jfp/article-abstract/84/7/1122/461503/Evaluation-of-Avocados-as-a-Possible-Source-of?redirectedFrom=fulltext