We report the detection of a Shigella sonnei outbreak from a small investigation in the San Francisco Bay area, California, USA, in 2024. By combining outbreak investigation with genomic sequencing, we show the utility of phylodynamics to aid outbreak investigations of bacterial pathogens by state or local public health departments.
Keywords: California; Shigella sonnei; United States; antimicrobial resistance; bacteria; epidemiology; multidrug resistance; outbreak; phylodynamic modelling.