An Outbreak Investigation of Salmonella Typhimurium Illnesses in the United States Linked to Packaged Leafy Greens Produced at a Controlled Environment Agriculture Indoor Hydroponic Operation - 2021.

In 2021, the U.S. Food and Drug Administration (FDA), the Centers for Disease Control and Prevention (CDC), and state partners investigated a multistate outbreak of Salmonella Typhimurium illnesses linked to packaged leafy greens from a controlled environment agriculture (CEA) operation in Illinois. Thirty-one illnesses and four hospitalizations were reported in four states, with a significant epidemiologic signal for packaged leafy greens from Farm A. A traceback investigation for leafy greens included seven points of service (POS) with food exposure data from eight ill people. Each POS was supplied leafy greens by Farm A. FDA investigators observed operations at Farm A and noted that 1) the firm did not consider their indoor hydroponic pond water as agricultural water, 2) condensate dripping from the chiller water supply line inside the building, and 3) unprotected outdoor storage of packaged soilless growth media and pallets used for finished product. FDA collected 25 product, water, and environmental samples from Farm A. The outbreak strain was recovered from a water sample collected from a stormwater drainage basin located on the property adjacent to Farm A. In addition, an isolate of Salmonella Liverpool was recovered from two indoor growing ponds within the same growing house, but no illnesses were linked to the isolate. Farm A voluntarily recalled all implicated products and provided their root cause analysis (RCA) and return-to-market plan to FDA. While the source and route of the contamination were not determined by the RCA, epidemiologic and traceback evidence confirmed the packaged salads consumed by ill persons were produced by Farm A. This was the first investigation of a multistate foodborne illness outbreak associated with leafy greens grown in a CEA operation. This outbreak demonstrated the need for growers using hydroponic methods to review their practices for potential sources and routes of contamination and to reduce food safety risks when identified.

Vitamin D deficiency in a nonrandom sample of southeast Alaska Natives.

Serum vitamin D has recently been inversely associated with risk for type 2 diabetes. Recent literature suggests that many more individuals than generally thought suffer from vitamin D deficiency. Southeast Alaskan Natives are at an increased risk due to limited sunlight exposure and possible inadequate vitamin D intake. Therefore, the relationship between vitamin D and glucose should be investigated specifically in the southeast Alaska Native population. A review of lab records yielded 83 charts of patients found to have a serum 25-hydroxyvitamin D during a 2-year period. Upon review of these charts, only nine of 83 vitamin D levels were found to exceed the 32 ng/mL (80 nmol/L) threshold. Age and vitamin D levels were associated in a positive linear relationship (r=0.354, P=0.028). The patients in the lowest vitamin D quartile were younger in age compared to the highest quartile (14.6 years, 95% confidence interval: 4.9, 24.29; P=0.004). The high rate of deficiency noted in this sample suggests this population should be further assessed for vitamin D deficiency. Future studies are needed to confirm the association between a vitamin D deficiency and diabetes incidence in this population.