Global phylogeny and evolutionary history of four major Brucella species

• 1、Pasteurien College,Soochow University,Suzhou 215004

Abstract：rucellosis is a serious zoonotic disease caused by Brucella species, posing a significant threat to public health worldwide. Although different Brucella species show high genetic similarity at the genomic level, they still exhibit different host preferences, zoonotic risks, and virulence. To better understand the genetic diversity of this pathogen, we selected a total of 1999 strains representing the four major Brucella species from public databases, and performed phylogenetic analysis based on whole genome sequencing. We constructed the core SNPs based phylogenetic tree and subdivided the Brucella population using the PopPunk software. We then used Bayesian inference to analyze the global evolution and systematic geographic spread of Brucella. We found that their most recent common ancestor could be traced back to approximately 5565 BC, suggesting that the genetic diversification of these major global Brucella lineages may be related to the early domestication and distribution of livestock. In addition, with the globalization since around AD 1000 and the further strengthening of global connections in the past two centuries, the four major Brucella lineages have undergone rapid subtype differentiation and population expansion, accompanied by accelerated global dissemination within their respective lineages. Our study provides important insights into the evolution and transmission of Brucella, which can aid in the development of better prevention and control strategies against Brucella .

Keywords： Brucella phylpgeny temporal evolution geographic dissemination