No abstract

This study was conducted to investigate the prevalence of coliforms and Escherichia coli across radish sprout production facilities in the Republic of Korea and to characterize isolated E. coli. A total of 324 samples were collected from three different radish sprout production units in spring and summer. Overall, the levels of coliforms were significantly higher (> 3.75 log CFU/g) in radish sprouts during summer season than in spring. E. coli was detected in the pre-harvest (50%) and post-harvest (39%) sprouts and water samples (33%) from farms B and C. Of the 48 E. coli isolates, five E. coli isolates were positive for the eaeA gene, indicative of EPEC O110, two isolates were eaeA-positive (EPEC ONT) and one isolate was ipaH-positive (ETEC O71). These three E. coli strains were identified as novel sequence types by the multilocus sequence-typing assay based on the combination of allelic profiles. In addition, the EPEC O110 isolates obtained from the stream water stored in container of farm C were toxic to Caenorhabditis elegans. It is necessary to implement safety measures during the production of radish sprouts to prevent E. coli outbreaks.