Population structure of serotype Mbandaka reveals similar virulence potential irrespective of source and phylogenomic stratification.

: serotype Mbandaka ( ser. Mbandaka) is a multi-host adapted Non-typhoidal (NTS) that can cause foodborne illnesses in human. Outbreaks of ser. Mbandaka contributed to the economic stress caused by NTS due to hospitalizations. Whole genome sequencing (WGS)-based phylogenomic analysis facilitates better understanding of the genomic features that may expedite the foodborne spread of ser. Mbandaka. : In the present study, we define the population structure, antimicrobial resistance (AMR), and virulence profile of ser. Mbandaka using WGS data of more than 400 isolates collected from different parts of the world. We validated the genotypic prediction of AMR and virulence phenotypically using an available set of representative isolates. : Phylogenetic analysis of ser. Mbandaka using Bayesian approaches revealed clustering of the population into two major groups; however, clustering of these groups and their subgroups showed no pattern based on the host or geographical origin. Instead, we found a uniform virulence gene repertoire in all isolates. Phenotypic analysis on a representative set of isolates showed a similar trend in cell invasion behavior and adaptation to a low pH environment. Both genotypic and phenotypic analysis revealed the carriage of multidrug resistance (MDR) genes in ser. Mbandaka. : Overall, our results show that the presence of multidrug resistance along with adaptation to broad range of hosts and uniformity in the virulence potential, isolates of ser. Mbandaka from any source could have the potential to cause foodborne outbreaks as well as AMR dissemination.