SalmonellaSenftenberg isolated from wastewater is linked to a 2022 multistate outbreak

The ability of wastewater-based surveillance (WBS) to infer viral loads in communities was showcased during the COVID-19 pandemic. Whether WBS could be used to track other microorganisms is less studies. We tested for Salmonella enterica , a common foodborne pathogen, in community wastewater and investigated whether such isolates could be linked to past or ongoing outbreaks. During June 2022, composite wastewater samples were collected from treatment facilities in two communities in central Pennsylvania. A total of 42 confirmed S. enterica isolates were whole genome sequenced, revealing 7 different serovariants. Four isolates identified as S. enterica ser. Senftenberg were in a cluster, separated by 0-4 SNPs from clinical isolates uploaded to the web-based National Centers for Biotechnology Information Pathogen Detection platform. Most isolates in the cluster were previously associated with a 2022 multistate foodborne outbreak that was caused by contaminated peanut butter. Our targeted study suggests that wastewater-based surveillance for Salmonella would complement public health efforts by providing information about the extent of an outbreak and help focus public health resources and guidance to areas most impacted.