Occurrence of Listeria Species in Fresh Seafood

Abstract

In order to clarify the status of contamination with Listeria spp. in commercial fresh seafood, a total of 683 samples were collected from wholesale and retail shops in the Tokyo metropolitan area and examined. Listeria spp. were detected in 68 (10.0%) of the 683 samples, and the detection rate tended to be higher in samples with a larger standard plate count. In most instances the Listeria species count was less than 10/g. The most frequently found Listeria species was L. innocua, from 51 samples (7.5%). L. monocytogenes was isolated from 12 samples (1.8%). The serotype of L. monocytogenes which was most frequently found was 4b, followed by 1/2a, 1/2b and 3b.