State Case Count as an Indicator of Successful Multistate Outbreak Investigation

Background/Objectives: Shiga-Toxin producing Escherichia coli (STEC) is a contaminant found in multiple food types and causes multistate outbreaks due to the industrialization of food production. In this report I examine the differences in outbreaks categorized by the regulating agency responsible in outbreak prevention and compare outbreak case counts when organized by positive outbreak investigation and response outcomes. Methods: STEC Multistate outbreak data was obtained from the Center for Disease Control’s National Outbreak Reporting System (NORS) for outbreaks occurring from 2006-2023. Outbreaks were organized into those regulated by either the US Food and Drug Administration (FDA) or the US Department of Agricultures’ Food Safety and Inspection Service (USDA-FSIS) according to the contaminated food. Description of outbreaks organized by regulating agency was performed for the number of outbreaks, STEC serotype, recall, outbreak cases, hospitalizations, HUS cases, and deaths. Comparison was also performed for total cases, outbreak duration, distribution, and public health response time. Total cases and highest state case counts were also compared between outbreaks organized into binary outbreak investigation variables. Results: Outbreak duration was significantly shorter in the FDA regulated foods. Medians of total cases and highest state case count were also higher in positive outbreak investigation variables.