Antimicrobial resistance and genetic relatedness of Salmonella serotypes isolated from food, asymptomatic carriers, and clinical cases in Shiyan, China

PLoS One. 2024 May 9;19(5):e0301388. doi: 10.1371/journal.pone.0301388. eCollection 2024.

Abstract

Salmonella is a primary cause of foodborne diseases globally. Despite food contamination and clinical infections garnering substantial attention and research, asymptomatic Salmonella carriers, potential sources of infection, have been comparatively overlooked. In this study, we conducted a comparative analysis of serotype distribution, antimicrobial resistance phenotypes, and genetic profiles of archived Salmonella strains isolated from food (26), asymptomatic carriers (41), and clinical cases (47) in Shiyan City, China. Among the 114 Salmonella strains identified, representing 31 serotypes and 34 Sequence Types (STs), the most prevalent serovars included Typhimurium, Derby, Enteritidis, Thompson, and London, with the most predominant STs being ST11, ST40, ST26, ST34, and ST155. Antimicrobial resistance testing revealed that all strains were only sensitive to meropenem, with 74.6% showing antimicrobial resistance (AMR) and 53.5% demonstrating multidrug resistance (MDR). Strains resistant to five and six classes of antibiotics were the most common. Pearson's chi-square test showed no statistically significant difference in the occurrence of AMR (p = 0.105) or MDR (p = 0.326) among Salmonella isolates from the three sources. Our findings underscore associations and diversities among Salmonella strains isolated from food, asymptomatic carriers, and clinical patients, emphasizing the need for increased vigilance towards asymptomatic Salmonella carriers by authorities.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents* / pharmacology
  • Carrier State / microbiology
  • China / epidemiology
  • Drug Resistance, Bacterial / genetics
  • Drug Resistance, Multiple, Bacterial / genetics
  • Food Microbiology
  • Humans
  • Microbial Sensitivity Tests
  • Salmonella Infections / drug therapy
  • Salmonella Infections / epidemiology
  • Salmonella Infections / microbiology
  • Salmonella* / classification
  • Salmonella* / drug effects
  • Salmonella* / genetics
  • Salmonella* / isolation & purification
  • Serogroup*

Substances

  • Anti-Bacterial Agents

Grants and funding

This work was supported by the Hubei Province Health and Family Planning Scientific Research Project (No. WJ2023M168), the Principal Investigator Program (HBMUPI202104); the Science Research and Development Project of Shiyan (2021K20). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.