Main content area

Serotypes and Pulsotypes Diversity of Listeria monocytogenes in a Beef-Processing Environment

Camargo, Anderson Carlos, Dias, Mariane Rezende, Cossi, Marcus Vinícius Coutinho, Lanna, Frederico Germano Piscitelli Alvarenga, Cavicchioli, Valéria Quintana, Vallim, Deyse Christina, Pinto, Paulo Sérgio de Arruda, Hofer, Ernesto, Nero, Luís Augusto
Foodborne pathogens & disease 2015 v.12 no.4 pp. 323-326
Listeria monocytogenes, cross contamination, hands, knives, meat cuts, meat processing, public health, pulsed-field gel electrophoresis, screening, serotypes
Utensils and equipment from meat-processing facilities are considered relevant cross-contamination points of Listeria monocytogenes to foods, demanding tracking studies to identify their specific origins, and predict proper control. The present study aimed to detect L. monocytogenes in a beef-processing facility, investigating the diversity of serotypes and pulsotypes in order to identify the possible contamination routes. Surface samples from knives (n=26), tables (n=78), and employees hands (n=74) were collected before and during the procedures from a beef-processing facility, in addition to surface samples of end cuts: round (n=32), loin (n=30), and chuck (n=32). All samples were subjected to L. monocytogenes screening according ISO 11.290-1, and the obtained isolates were subjected to serotyping and pulsed-field gel electrophoresis. Listeria spp. were identified in all processing steps, in 61 samples, and L. monocytogenes was detected in 17 samples, not being found only in knives. Eighty-five isolates were identified as L. monocytogenes, from serotypes 1/2c (n=65), 4b (n=13), and 1/2b (n=7), being grouped in 19 pulsotypes. Considering these results, cross-contamination among hands, tables, and beef cuts could be identified. The obtained data indicated the relevance of cross-contamination in the beef-processing facility, and the occurrence of serotypes 1/2b and 4b in beef cuts distributed for retail sale is a public health concern.