# Genomic Modeling of an Outbreak of Multidrug-Resistant Shigella sonnei, California, USA, 2023–2024

## TL;DR

This paper describes a Shigella sonnei outbreak in California and shows how genomic sequencing can help track and manage bacterial disease outbreaks.

## Contribution

The study demonstrates the practical use of phylodynamics in outbreak investigations by local health departments.

## Key findings

- A Shigella sonnei outbreak was detected in the San Francisco Bay area in 2024.
- Genomic sequencing and phylodynamics were used to trace the outbreak's spread and source.

## Abstract

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.