Nationwide surveillance in Thailand revealed genotype-dependent dissemination of carbapenem-resistant Enterobacterales

Carbapenem-resistant Enterobacterales (CRE) are a serious public health threat because of their rapid dissemination. To determine the epidemiological and genetic characteristics of CRE infections in Thailand, we performed whole-genome sequencing of 577 carbapenem-resistant Klebsiella pneumoniae isolates and 170 carbapenem-resistant Escherichia coli isolates from hospitals across the nation. The four most prevalent carbapenemase genes harboured by these bacteria were bla NDM-1 , bla NDM-5 , bla OXA-181 and bla OXA-232 . The gene bla NDM-1 was identified in diverse sequence types. The gene bla NDM-5 was identified almost exclusively in E. coli . The genes bla OXA-181 , bla OXA-232 , and co-carriage of bla NDM-1 and bla OXA-232 were found in specific sequence types from certain provinces. Replicon typing revealed the diverse backbones of bla NDM-1 - and bla NDM-5 -harbouring plasmids and successful expansion of bla NDM-1 -harbouring IncN2-type plasmids. Core-genome single-nucleotide polymorphism analysis suggested that bla OXA-181 -, bla OXA-232 -, bla NDM-5 -, and co-carriage of bla NDM-1 and bla OXA-232 -associated sub-clonal lineages have recently predominated in the provinces from where these isolates were isolated. Thus, we demonstrate genotype-dependent dissemination of CRE in Thailand, which is helpful for establishing infection-control strategies in CRE-endemic areas.