When a dangerous strain of E. coli sickened more than 60 employees of a large company in Germany last spring, health investigators turned to the electronic billing records kept by two in-house cafeterias to accurately identify fenugreek sprouts as the cause.
Details of the investigation in Frankfurt, Germany, were reported in this month’s issue of Emerging Infectious Diseases published by the Centers for Disease Control and Prevention (CDC). The study authors, including experts from Germany’s Robert Koch Institute and Frankfurt’s Health Protection Authority, said billing data from the company’s two cafeteria sites allowed for a rapid discovery of the outbreak’s cause at a time when intense media speculation over the cause of the outbreak made it difficult to rely on people’s memories of what they had eaten.
The outbreak among cafeteria patrons at the Frankfurt company was termed a “satellite” of the much larger E. coli O104:H4 outbreak that killed 50 people and sickened more than 4,000 others in 15 countries, mostly in Europe. It was the largest outbreak ever described worldwide in terms of hemolytic uremic syndrome (HUS), a complication of toxic E. coli infection that shuts down a person’s kidneys and can lead to other severe illness, including stroke and heart attack.
“Sprouts available in the Frankfurt cafeteria salad bars were traced back to a producer of fenugreek sprouts, which appear to be the common source of primary cases in the entire outbreak,” the study authors wrote.
The investigators identified 60 company employees who were either hospitalized with bloody diarrhea or HUS or who self-reported onset of bloody diarrhea from May 8 through May 23. Only three of the case patients remained unexposed to salad bar items according to the payment system data.