Detection of Listeria spp. in food handling areas of retail food stores in the state of Pernambuco, Brazil

Abstract

The identification of Listeria spp. in food handling areas is of great concern to health surveillance agencies, and their control is often hampered by the ability of the bacteria to grow and maintain themselves even under adverse conditions. The present study aimed to isolate and identify Listeria spp. in the food handling areas of 10 retail food stores in the state of Pernambuco, Brazil. Eighty-six swab samples were collected from equipment, utensils and surfaces used for processing ready-to-eat meat products. The Dry and Wet Swabbing Methods (3M" Quick Swabs) and 3M" Petrifilm" Plates were used to identify Listeria spp. Contamination by Listeria monocytogenes was confirmed by the Real-time Polymerase Chain Reaction (qPCR). The hygienic and sanitary conditions of the food handling areas of each store were also assessed. Listeria spp. was isolated in eight stores (80%). Of the 86 swab samples analyzed, 27 (31.2%) [confidence interval 21.81% to 42.30%] were positive for Listeria spp. and only one (3.7%) was confirmed as Listeria monocytogenes. The main contamination sites were the floor (50.0%), the plastic cutting board (42.9%) and the knife (40.0%). None of the hygienic and sanitary conditions assessed in the present study were associated with contamination by Listeria spp. (p = 0.700). It was concluded that Listeria spp. was widely distributed in the retail food stores studied, being a possible risk factor for public health.