L. monocytogenes isolates in persistent clades contained, on average, more prophages and other mobile genetic elements (MGEs) than isolates in nonpersistent clades. (a) L. monocytogenes isolates in this study represented 25 unique sequence types (STs), and persistent clades were detected among the six most prevalent STs. Each circle represents a unique ST, and the area of the circle corresponds to the number of isolates. For each ST in which persistent clades were detected, doughnut charts illustrate the proportion of isolates in persistent (pink) and nonpersistent (aquamarine) clades. (b, c) Distribution of isolates by numbers of nonphage MGEs (b) and prophages (c) per genome among isolates in persistent and nonpersistent clades. The average number of the elements per genome is also given.