Bayesian phylogeographic analysis infers cross-border transmission dynamics of drug-resistant <i>Salmonella</i> Enteritidis

Antimicrobial resistance and disease severity in nontyphoidal <i>Salmonella</i> have constituted a serious public health challenge worldwide. Drug-resistant <i>Salmonella</i> Enteritidis is a leading pathogen that causes human infections primarily through the consumption of contaminated food products. Previous research focuses on the whole-genome analysis of antimicrobial resistance and virulence factors in <i>S</i>. Enteritidis; however, details on how this bacterium localized, expanded, and diversified from location to location remain unknown. Our study for the first time addresses this gap by investigating the phylogeographic transmission to estimate the frequency and location of cross-border spread. By evidence-based inferred transmission, we aim to uncover novel insights into the dynamic spread of <i>S</i>. Enteritidis, revealing the route of emergence and migration. This research is crucial for enhancing our understanding of the control strategies to safeguard human health.