bla_NDM-5-encoding ST171 Enterobacter hormaechei: A global genomic and epidemiological perspective

Area of Science:

• Microbiology
• Genomics
• Epidemiology

Background:

• Carbapenem-resistant Enterobacteriaceae (CRE) pose a significant global health threat.
• The blaNDM-5 gene confers resistance to carbapenems, a last-resort antibiotic class.
• Enterobacter hormaechei is an opportunistic pathogen frequently associated with healthcare-associated infections.

Purpose of the Study:

• To conduct a comprehensive genomic and epidemiological analysis of ST171 Enterobacter hormaechei isolates harboring the blaNDM-5 gene.
• To investigate the global emergence and dissemination patterns of these specific strains.

Main Methods:

• Whole-genome sequencing (WGS) using Illumina technology.
• Bioinformatic analysis of genomic characteristics and antimicrobial resistance genes.
• Phylogenetic analysis using single nucleotide polymorphism (SNP) data to determine clonal relationships.

Main Results:

• Six blaNDM-5-positive ST171 E. hormaechei strains were isolated from an emergency intensive care unit in China.
• These strains exhibited multidrug resistance, with 12 antimicrobial resistance genes identified, including blaNDM-5.
• Phylogenetic analysis confirmed a single clonal lineage, indicating nosocomial transmission. A global search identified 75 blaNDM-5-positive ST171 E. hormaechei strains, predominantly from clinical sources, with high prevalence in China and the United States, showing clonal dissemination across healthcare facilities.

Conclusions:

• blaNDM-5-positive ST171 E. hormaechei strains represent an emerging global threat.
• Clonal spread within and between healthcare facilities highlights the need for robust infection control measures.
• Continuous surveillance is essential for effective prevention and control of antimicrobial resistance associated with these strains.