Betancor et al. [5] examine 266 isolates of
Salmonella enterica serovar Enteritidis comparing their genomes and looking for genetic variability in the strains that have been causing a Salmonellosis epidemic in Uruguay. An important take home message from this study was that much of the genetic variability of these isolates has come from phage infection and excision. Phage may turn out to be a major mechanisms of genetic change and may be involved in modulating virulence.