blaNDM-1 Carried by a Transferable Plasmid in a Salmonella Strain Isolated from Healthy Individuals

• Published in: Biomedical and environmental sciences Vol. 37; no. 11; pp. 1252 - 1261
• Main Authors: Zeng, Wei, Luo, Ming, Du, Pengcheng, Li, Zhenpeng, Peng, Yao, Wang, Mengyu, Zhao, Wenxuan, Zhang, Huayao, Li, Yang, Luo, Pengjie, Wu, Yannong, Xu, Jialiang, Li, Xu, Lu, Xin, Kan, Biao
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.11.2024; National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases,National Institute for Communicable Disease Control and Prevention,Chinese Center for Disease Control and Prevention,Beijing 102206,China; Yantai Center for Disease Control and Prevention,Yantai 264003,Shandong,China; School of Public Health,Shandong University,Jinan 250012,Shandong,China%NHC Key Laboratory of Food Safety Risk Assessment,China National Center for Food Safety Risk Assessment(CFSA),Beijing 100022,China%School of Food and Chemical Engineering,Beijing Technology and Business University,Beijing 100048,China; School of Public Health,Shandong University,Jinan 250012,Shandong,China%Yulin Center for Disease Control and Prevention,Yulin 537000,Guangxi,China%Qitan Technology Ltd.,Chengdu 610044,Sichuan,China%National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases,National Institute for Communicable Disease Control and Prevention,Chinese Center for Disease Control and Prevention,Beijing 102206,China%National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases,National Institute for Communicable Disease Control and Prevention,Chinese Center for Disease Control and Prevention,Beijing 102206,China
• Subjects: Carbapenems; Healthy individual; IncHI2/IncHI2A plasmid; NDM-1; Salmonella Typhimurium; NDM-1; Healthy individual; Carbapenems; IncHI2/IncHI2A plasmid; Salmonella Typhimurium; lncHI2/lncHI2A plasmid
• ISSN: 0895-3988
• DOI: 10.3967/bes2024.104

Our study aimed to conduct genomic characterization of Salmonella strains carrying the blaNDM-1 gene in the intestinal tract of healthy individuals. The objectives were to underscore the importance of genomic surveillance for drug resistance in both commensal and pathogenic bacteria among healthy populations, and to establish protocols for regulating drug resistance plasmids based on the completion of a comprehensive map of drug resistance plasmid genomes. We performed antimicrobial susceptibility testing and employed second- and thirdgeneration sequencing techniques to analyze Salmonella strains harboring the blaNDM-1 gene, to surveil drug-resistant bacteria in the intestines of healthy subjects. Sequence comparison was conducted using both core- and pan-genome approaches. Concurrently, conjugation experiments were carried out to assess the efficiency of plasmid transfer. We isolated a carbapenem-resistant Salmonella enterica serovar Typhimurium strain from a healthy food worker in China. This strain harbored an IncHI2/IncHI2A plasmid carrying blaNDM-1 along with multiple antibiotic resistance genes (ARGs). Our findings highlight the potential for asymptomatic carriers to facilitate the transmission of ARGs. Pan-genomic analysis revealed that blaNDM-1-positive plasmids could traverse bacterial species barriers, facilitating cross-host transmission. This study marks the first detection of blaNDM-1 in Salmonella strains isolated from healthy individuals. We underscore the risk associated with the transmission of conjugative hybrid plasmids carrying blaNDM-1, which have the potential to be harbored and transmitted among healthy individuals. Enhanced surveillance of drug-resistant pathogens and plasmids in the intestinal microbiota of healthy individuals could provide insights into the risk of ARG transmission and pathways for population-wide dissemination via ARG transfer factors.