Incidence and characterization of Listeria monocytogenes from domestic andimported foods in Korea

A total of 1,537 domestic and imported food products were examined for the incidence of Listeria monocytogenes between 1993 and 1997 in Korea. L. mono cytogenes was detected using the U.S. Department of Agriculture isolation m ethod. Isolated L. monocytogenes was confirmed by polymerase chain reaction with hly1 and hly2 primers designed from the listeriolysin O. Overall, 122 samples (7.9%) contained L. monocytogenes. The rate of isolation was 4.3% for beef, 19.1% for pork, 30.2% for chicken, 1.2% for shellfish, 4.4% for r aw milk, 4.4% for frozen smoked mussels, and 6.1% for ice cream. No L, mono cytogenes was found in pasteurized milk pasteurized processed cheese, saltw ater fish, dried seafoods, or ham. The overall incidence was lower than tha t reported in previous studies from other countries. Most isolates were ser otype 1/2b except for chicken, in which serotype 1/2a was predominant. The serotyping results might imply the presence of food or geography-specific L . monocytogenes strains.