CDC published an investigation into a Salmonella outbreak that was linked to a improperly cleaned ice cooler that held beer. Investigators used AI to help them deduce the obvious. Important to point out that this occurred in Illinois (important to know it was not in your state).
"All 13 persons who became ill reported 1) spending time in the infield area and 2) drinking canned beer from the beer tent. No illnesses were identified among persons who did not access the beer tent."
"Fair organizers reported that the large improvised cooler in the beer tent consisted of a 10-ft length of non–food-grade corrugated black plastic farm drainage tile with four internal compartments. The cooler was only meant to contain ice and cans of beer. The ice for the fair was provided by a single local company and produced from a municipal water supply, and all fair vendors had access to the same ice for use in their vendor stalls. The cooler was rinsed out with a hose once at the beginning of the week. The cooler was not rinsed again and was never cleaned with soap, and no means for monitoring the cooler’s internal temperature was available. Staff members handled the ice and cans with their bare hands. Handwashing stations were not available inside the beer tent. Cans were kept submerged in ice, and the melted ice was replenished daily. The cooler was designed to drain through a single spigot; however, standing water was reported, suggesting incomplete drainage. Different staff members worked at the beer tent each night, including two persons who later received test results positive for salmonellosis; both reported drinking beer at the beer tent and were the only staff members who reported illness. The standing water in the cooler was not reported until after the fair had concluded and was not available for testing, nor was the cooler itself. No standardized cleaning or sanitization procedures for the cooler were reported."
"Because the investigation began >1 week after the fair concluded, the ice and water were no longer available for testing, nor was the cooler. In the absence of other common food or environmental exposures, contamination of the ice used for beer storage was considered a plausible source for the outbreak."
Conclusion - "In this outbreak of S. Agbeni among attendees at a county fair, persons who became ill had purchased food from different vendors on different days, and four patients had not eaten at the fair at all, suggesting that an exposure other than food was the source of infection. The outbreak was linked to ice water used to store and chill beverages, which was likely contaminated. Transmission through improper ice- or beverage-handling practices is rarely reported (4). Because all the ice used at the fair was produced by a single local vendor, used a municipal water supply, and was distributed uniformly to all vendors, contamination at the source was considered unlikely. A more plausible explanation is that the ice became contaminated secondarily through improper handling practices, such as direct contact with contaminated food stored in coolers or via fecal-oral transmission from inadequate hand hygiene. Use of improvised beverage storage equipment that could not be adequately drained likely contributed to this outbreak; consequently, routine sanitization of ice coolers is now required. These pathways are consistent with known transmission routes for Salmonella spp. and highlight the importance of strict food safety and hygiene protocols during mass gatherings. Although consumption of contaminated food is the most common route for the spread of Salmonella, this investigation highlights the importance of considering uncommon exposures (7)."
https://www.cdc.gov/mmwr/volumes/75/wr/mm7507a1.htm
Multicounty Outbreak of Salmonella Agbeni Linked to Ice in a Cooler at a County Fair — Illinois, August 2024
Weekly / February 26, 2026 / 75(7);93–97
Katherine E. Houser1 (View author affiliations)
