John Luchansky, U.S. Department of Agriculture-ARS-ERRC, Wyndmoor, PA
Anna Porto-Fett, U.S. Department of Agriculture-ARS-ERRC, Wyndmoor, PA
Sherri Dennis, U.S. Food and Drug Administration, College Park, MD
Yuhuan Chen, U.S. Food and Drug Administration-CFSAN, College Park, MD
Regis Pouillot, U.S. Food and Drug Administration-CFSAN, College Park, MD
Karin Hoelzer, U.S. Food and Drug Administration, Washington, DC
Laura Gathercole, U.S. Food and Drug Administration-HHS, College Park, MD
Lori Papadakis, U.S. Food and Drug Administration-HHS, College Park, MD
Laurie Williams, U.S. Food and Drug Administration-HHS, College Park, MD
Bradley Shoyer, U.S. Department of Agriculture-ARS-ERRC, Wyndmoor, PA
Jeehyun Lee, Drexel University, Philadelphia, PA
James Lindsay, U.S. Department of Agriculture-ARS-NPS, Beltsville, MD
Janell Kause, U.S. Department of Agriculture-FSIS, Manassas, VA
Evelyne Mbandi, U.S. Department of Agriculture-FSIS, Ellicott City, MD
Denise Eblen, U.S. Department of Agriculture-FSIS, Washington, DC
William Shaw, U.S. Department of Agriculture-FSIS, Washington, DC
Daniel Gallagher, Virginia Tech, Blacksburg, VA
L. Victor Cook, U.S. Department of Agriculture-FSIS, Washington, DC
Nathan Bauer, U.S. Department of Agriculture-FSIS, College Station, TX
Rachel Johnson, U.S. Department of Agriculture-FSIS, Washington, DC
John King, Drexel University, Philadelphia, PA
Melissa Murphy, Drexel University, Philadelphia, PA
James Nasella, Drexel University, Philadelphia, PA
Holland Starks, Drexel University, Philadelphia, PA
Sheeri Khokhar, Drexel University, Philadelphia, PA
Christopher Spurlino, Drexel University, Downingtown, PA
Trang Nguyen, Drexel University, Philadelphia, PA
Katrina Berry, Drexel University, Philadelphia, PA
Alisa Kanjanakorn, Drexel University, Philadelphia, PA
Sarah Wadsworth, Food Safety Connect, Blacksville, WV
Elizabeth Baker, Drexel University, Philadelphia, PA
Caitlin Harvey, Drexel University, Philadelphia, PA
China Reed, Drexel University, Philadelphia, PA
Karina Martino, University of Georgia, Athens, GA
Lisa Benjamin, Western Institute of Food Safety and Security, Davis, CA
Introduction: Although significant efforts have been taken to control
Lm in RTE foods over the last decade, a well-designed survey is needed to determine whether changes occur in the “true” prevalence and levels of the pathogen and to provide current data to assess the relative ranking of higher risk foods.
Purpose: A multi-agency, multi-disciplinary study was undertaken to determine the current prevalence and levels of Lmin deli-packaged versus prepackaged RTE foods purchased at retail establishments in four FoodNet sites.
Methods: Phase I of the study included ten product categories: smoked seafood, seafood salad, low acid cut fruits, soft cheese, deli salads (non-meat), raw milk, sandwiches, deli meats, deli salads containing meat, and dried/fermented sausage. Samples were collected in both supermarket chain and independent grocery stores in California, Maryland, Connecticut and Georgia over a 12-month period beginning December 2010. Collaborations between FDA, FSIS, ARS and several universities enabled the collection of a representative and sufficient number of samples. Samples were analyzed using the FDA-BAM method, which includes screening (25 gram or ml per each sample) and enumeration of positive samples by the MPN method and direct plating.
Results: Of the ca.7,500 FDA regulated samples tested to date, the observed prevalence ranged from ca. 0% to 1.0% for seven product categories. The prevalence data for the ca. 3,500 FSIS-regulated products are currently being analyzed. For the 43 samples testing positive during screening, Lm levels ranged from ca. <0.3 MPN/g to 2.4 log CFU/g.
Significance: This is the most comprehensive survey of Lm in retail RTE foods in the past decade. Our findings provide data to assess changes in Lm prevalence and levels in RTE foods and will be used to update the 2003 Interagency Lm risk assessment. The study also underscores the importance of continued research to develop and validate interventions to ensure a wholesome food supply.
