Antimicrobial Resistance in Salmonella Isolated from Food Workers and Chicken Products in Japan

Yoshimasa Sasaki; Hiromi Kakizawa; Youichi Baba; Takeshi Ito; Yukari Haremaki; Masaru Yonemichi; Tetsuya Ikeda; Makoto Kuroda; Kenji Ohya; Yukiko Hara-Kudo; Tetsuo Asai; Hiroshi Asakura

doi:10.3390/antibiotics10121541

Antimicrobial Resistance in Salmonella Isolated from Food Workers and Chicken Products in Japan

Antibiotics (Basel). 2021 Dec 16;10(12):1541. doi: 10.3390/antibiotics10121541.

Authors

Yoshimasa Sasaki^{1

2}, Hiromi Kakizawa³, Youichi Baba³, Takeshi Ito³, Yukari Haremaki⁴, Masaru Yonemichi⁴, Tetsuya Ikeda⁵, Makoto Kuroda⁶, Kenji Ohya⁷, Yukiko Hara-Kudo⁷, Tetsuo Asai², Hiroshi Asakura^{1

2}

Affiliations

¹ Division of Biomedical Food Research, National Institute of Health Sciences, 3-25-26, Tonomachi, Kawasaki-ku, Kawasaki 210-9501, Kanagawa, Japan.
² Department of Applied Veterinary Science, The United Graduate School of Veterinary Science, Gifu University, 1-1, Yanagido, Gifu 501-1193, Gifu, Japan.
³ Incorporated Foundation Tokyo Kenbikyo-in, 1-100-38 Takamatsu-cho, Tachikawa 190-0011, Tokyo, Japan.
⁴ BML Food Science Solutions, Inc., 1549-7, Matoba, Kawagoe 350-1101, Saitama, Japan.
⁵ Department of Infectious Diseases, Hokkaido Institute of Public Health, Kita19 Nishi 12, Kita-ku, Sapporo 060-0819, Hokkaido, Japan.
⁶ Pathogen Genomics Center, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan.
⁷ Division of Microbiology, National Institute of Health Sciences, 3-25-26, Tonomachi, Kawasaki-ku, Kawasaki 210-9501, Kanagawa, Japan.

Abstract

Salmonella is an enteric bacterial pathogen that causes foodborne illness in humans. Third-generation cephalosporin (TGC) resistance in Salmonella remains a global concern. Food workers may represent a reservoir of Salmonella, thus potentially contaminating food products. Therefore, we aimed to investigate the prevalence of Salmonella in food workers and characterize the isolates by serotyping and antimicrobial susceptibility testing. Salmonella was isolated from 583 (0.079%) of 740,635 stool samples collected from food workers between January and December 2018, and then serotyped into 76 Salmonella enterica serovars and 22 untypeable Salmonella strains. High rates of antimicrobial resistance were observed for streptomycin (51.1%), tetracycline (33.1%), and kanamycin (18.4%). Although isolates were susceptible to ciprofloxacin, 12 (2.1%) strains (one S. Infantis, one S. Manhattan, two S. Bareilly, two S. Blockley, two S. Heidelberg, two S. Minnesota, one S. Goldcoast, and one untypeable Salmonella strain) were resistant to the TGC cefotaxime, all of which harbored β-lactamase genes (bla_CMY-2, bla_CTX-M-15, bla_CTX-M-55, and bla_TEM-52B). Moreover, 1.3% (4/309) of Salmonella strains (three S. Infantis and one S. Manhattan strains) isolated from chicken products were resistant to cefotaxime and harbored bla_CMY-2 or bla_TEM-52B. Thus, food workers may acquire TGC-resistant Salmonella after the ingestion of contaminated chicken products and further contaminate food products.

Keywords: Salmonella; antimicrobial resistance; chicken product; food worker.