Protracted, Intermittent Outbreak of Salmonella Mbandaka Linked to a Restaurant — Michigan, 2008–2019

Abstract

What is already known about this topic? Restaurant outbreaks of Salmonella with Salmonella-positive environmental samples might result in a higher proportion of Salmonella-positive food workers and longer outbreaks. What is added by this report? A protracted restaurant-associated outbreak of Salmonella Mbandaka in Michigan was identified through recursive case interviewing, asymptomatic employee testing, and environmental sampling. Multiple efforts to eradicate the organism failed, and the restaurant was permanently closed in 2018. What are the implications for public health practice? Coupling asymptomatic food worker testing and environmental sampling for Salmonella with whole genome sequencing of case isolates in suspected, protracted restaurant outbreaks of Salmonella enhances source identification. Exclusion or restriction of asymptomatic food workers with nontyphoidal Salmonella should be considered part of restaurant outbreak mitigation.