Prevalence and Antimicrobial Susceptibility of Enterobacteriaceae Isolated from Retail Pepper in Vietnam

Tetsuya Harada; Ryoko Yamane; Van Chinh Dang; Do Phuc Nguyen; Thi Anh Dao Nguyen; Michio Jinnai; Shinya Yonogi; Ryuji Kawahara; Masashi Kanki; Takao Kawai; Kentaro Kawatsu; Yuko Kumeda; Yuji Isegawa; Yoshimasa Yamamoto

doi:10.4315/0362-028X.JFP-16-501

Prevalence and Antimicrobial Susceptibility of Enterobacteriaceae Isolated from Retail Pepper in Vietnam

J Food Prot. 2016 May 1;80(5):716-724. doi: 10.4315/0362-028X.JFP-16-501.

Authors

Affiliations

¹ Osaka Prefectural Institute of Public Health, Nakamichi 1-3-69, Higashinari-ku, Osaka 537-0025, Japan.
² Mukogawa Women's University, 6-46 Ikebiraki, Nishinomiya, Hyogo 663-8558, Japan.
³ Institute of Public Health, 159 Hung Phu, District 8, Ward 8, Ho Chi Minh City 751301, Vietnam; and.
⁴ Global Collaboration Center, Osaka University, 2-7 Yamadaoka, Suita, Osaka 565-0871, Japan.

PMID: 28350183
DOI: 10.4315/0362-028X.JFP-16-501

Abstract

To investigate the microbial quality of retail pepper in Vietnam, the enumeration and detection of Enterobacteriaceae and the screening of cefotaxime (CTX)-resistant coliforms were performed by using 84 commercial samples. Although Enterobacteriaceae were isolated from 78 samples, the number of Enterobacteriaceae was lower than 1.0 log CFU/g in 46 samples. For the detection of Enterobacteriaceae with the International Organization for Standardization methods, Salmonella spp., Escherichia coli, Klebsiella pneumoniae, Cronobacter sakazakii, and Enterobacter cloacae complex were isolated from 5, 12, 36, 19, and 30 samples, respectively. During screening of CTX-resistant coliforms, K. pneumoniae, C. sakazakii, and E. cloacae complex were isolated from 8, 1, and 21 samples, respectively. Seven K. pneumoniae and seven E. cloacae complex isolates obtained in the screening of CTX-resistant coliforms were resistant to at least one of the three third-generation cephalosporins (CTX, ceftazidime, and cefpodoxime). Moreover, one E. cloacae complex cluster IV and all K. pneumoniae isolates were positive for extended-spectrum β-lactamase genes or plasmid-mediated AmpC β-lactamase genes or both. Additionally, two extended-spectrum β-lactamase-producing K. pneumoniae isolates and one AmpC β-lactamase-producing E. cloacae complex cluster IV isolate were positive for the plasmid-mediated quinolone resistance determinants and also had amino acid alterations in the quinolone resistance-determining regions of GyrA and ParC. Furthermore, 10 E. cloacae complex isolates were positive for the plasmid-mediated fosfomycin resistance gene fosA. As pepper is often consumed without a heating process, the possible spread to humans of foodborne, opportunistic, and nosocomial infection pathogens or resistance genes from foods prepared or seasoned with pepper cannot be excluded. Therefore, it is necessary to handle pepper by using hygienic conditions during the cultivation, harvesting and processing steps.

Keywords: Enterobacteriaceae; Vietnam; pepper.