from E. Fidelma Boyd writing in Foodborne and Waterborne Bacterial Pathogens: Epidemiology, Evolution and Molecular Biology:
The acquisition of new phenotypes by bacteria is largely driven by horizontal gene transfer (HGT), a process that is ubiquitous among bacteria and universally present among enteric pathogens. The common vectors of HGT in enteric pathogens include phages, pathogenicity islands and plasmids, all genetic elements that can encode virulence factors essential for host colonization and infection. In this review, Salmonella enterica, Escherichia coli, Vibrio cholerae and V. parahaemolyticus are discussed in terms of their virulence genes encoded within mobile and integrative genetic elements and their role in the mechanism of pathogenesis.
Further reading: Foodborne and Waterborne Bacterial Pathogens: Epidemiology, Evolution and Molecular Biology