In July and August of 2021, the U.S. Food and Drug Administration (FDA), Centers for Disease Control and Prevention (CDC), and state partners conducted research following several outbreaks of Salmonella Typhimurium. These outbreaks were linked to packaged leafy greens produced at an indoor hydroponic operation.
In total, 31 people fell ill, whilst only 4 people had to visit the hospital. Fortunately, nobody passed away. The outbreaks took place in Illinois (18), Michigan (1), Pennsylvania (2), and Wisconsin (10).
The outbreak response investigation found that the outbreak was associated with the consumption of packaged leafy greens from an indoor hydroponic operation; 26 of 27 (96%) patients reported consuming any leafy greens prior to illness onset, with 20 of 24 cases reporting consumption of prepackaged salads.
Loyalty card data was received for nine cases. The information identified a common brand of packaged salads and the traceback investigation determined all of the points-of-service (POS) were supplied by the same hydroponic operation owned and operated by this firm. The firm’s salad products purchased by ill consumers were confirmed to be produced at the firm’s hydroponic operation.
"Although a conclusive root cause was not identified, the agency identified certain conditions and practices that could result in contamination, including the presence of a different serotype of Salmonella in pond water used to grow the leafy greens, growth media storage practices, water management practices, and general sanitation practices at the CEA that were inadequate to prevent the introduction or spread of microorganisms of public health significance into the leafy greens," stated the FDA.
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