title: Prevalence and contamination levels of listeria monocytogenes in ready-to-eat foods in Tokyo, Japan.
abstract: We surveyed prevalence and contamination levels of Listeria monocytogenes in ready-to-eat foods between 2000 and 2012 in Tokyo. L. monocytogenes was isolated from 52 (1.7%) out of 2,980 samples. Comparing the prevalence in the study period, 2.2% were positive in the former period (2000-2005) and 1.2% in the latter (2006-2012). Using the most probable number (MPN) technique, 32 samples were contaminated with fewer than 0.3 L. monocytogenes/g, 10 samples with 0.3-1.0/g and 4 samples with more than 1.0/g (the maximum was 2.3/g). The most common serovar was 1/2a, followed by 1/2b, 4b and 1/2c. We revealed that ready-to-eat foods in Tokyo were contaminated with L. monocytogenes, although the contamination levels were low.
authors.affiliation: Department of Microbiology, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunin-cho, Shinjuku-ku, Tokyo 169-0073, Japan.
authors.forename: Yukako
authors.initials: Y
authors.lastname: Shimojima
authors.forename: Miki
authors.initials: M
authors.lastname: Ida
authors.forename: Akiko
authors.initials: A
authors.lastname: Nakama
authors.forename: Yukari
authors.initials: Y
authors.lastname: Nishino
authors.forename: Rie
authors.initials: R
authors.lastname: Fukui
authors.forename: Sumiyo
authors.initials: S
authors.lastname: Kuroda
authors.forename: Akihiko
authors.initials: A
authors.lastname: Hirai
authors.forename: Akemi
authors.initials: A
authors.lastname: Kai
authors.forename: Kenji
authors.initials: K
authors.lastname: Sadamasu
mesh_terms: D057140:Fast Foods / Q000382:microbiology*; D005506:Food Contamination / Q000706:statistics & numerical data; D005516:Food Microbiology; D007564:Japan; D008089:Listeria monocytogenes / Q000302:isolation & purification*; D015995:Prevalence