Purpose: To characterize microbial contamination and foodborne pathogens found in consumer kitchens in order to better understand the role that the domestic environment serves as a potential reservoir for infectious organisms.
Methods: Environmental samples were collected from the homes of 100 consumers in Philadelphia, PA. A total of 559 samples were collected from various surfaces in the kitchen, including the sink (n = 100), counter (n = 100), refrigerator shelf (n = 102), refrigerator drawer (n = 61), refrigerator door handle (n = 100), and a used dishcloth or sponge (n = 96). Each sample was tested for coliforms, fecal coliforms, E. coli, Staphylococcus aureus, Salmonella, Campylobacter and Listeria according to methods described by the Food and Drug Administration (FDA).
Results: Staphylococcus aureus was isolated from 13.1% of all 559 samples, most often from kitchen counter tops (17.0%), refrigerator door handles (16.0%), and kitchen sinks (14.0%). Listeria spp., including L. monocytogenes and L. innocua, were present on 2.3% of all samples and 9.8% of refrigerator drawers. Escherichia coli was isolated from 6% of kitchen sinks and 2.1% of kitchen sponges/dishcloths. Campylobacter jejuni was isolated from 3 households (3%), one time each from a sink, counter and dishcloth. Salmonella was not isolated from any kitchens in this study.
Significance: These results indicate that the domestic kitchen may serve as a reservoir for infectious organisms including Staphylococcus aureus, E. coli, C. jejuni and Listeria monocytogenes.