In late July of 1999, Ohio public health officials began receiving reports that patients at local hospitals in Cincinnati were suffering from E. coli O157:H7 infections. By August 2, 1999, fifteen cases had been confirmed, and through investigative interviews the Ohio Department of Health learned that eleven of those fifteen people had eaten foods purchased from KFC restaurants in southwestern Ohio counties in the week before becoming ill.
The Centers for Disease Control and Prevention (CDC) joined the epidemiologic investigation, and isolates were requested from all culture-confirmed cases so that pulse-field gel electrophoresis (PFGE) analysis, or “genetic fingerprinting” could be performed at the Ohio Department of Health Laboratory. Twelve culture-confirmed cases were found to have identical PFGE patterns in their E. coli O157:H7 isolates. This PFGE pattern was recognized as the outbreak strain.
Subsequent case-control studies conducted by public health investigators identified KFC coleslaw as the source of the E. coli outbreak. When sanitarians visited the implicated KFC restaurants, they found a number of deficiencies in the preparation of the coleslaw that could have contributed to the outbreak. Three particular food-handling errors were noted as possible explanations for the E. coli contamination in the coleslaw: inclusion of outer cabbage leaves, insufficient washing of cabbage, and the use of unpeeled carrots in the coleslaw.
We represented a woman who became ill with an E. coli O157:H7 infection and hemolytic uremic syndrome. She was hospitalized for nearly a month with acute renal failure and other life-threatening complications and nearly died twice. As a result of her E. coli O157:H7 infection, the woman suffered permanent and irreversible injury to her kidneys, pancreas, heart, lungs, and brain.
A Case-control study implicated KFC coleslaw as the vehicle for transmission of E. coli O157:H7. According to an Ohio Department Press Release:
“Sanitarians visited the involved KFCs and found a number of deficiencies in the preparation of the coleslaw, such as inclusion of outer cabbage leaves, insufficient washing of cabbage, and use of unpeeled carrots in the coleslaw.”
The final report found that the “[c]abbage was the likely contaminated ingredient in the coleslaw.” The Department of Health also noted:
“In response to this outbreak, KFC’s throughout Ohio are changing preparation procedures for coleslaw. Previously, coleslaw was made from cabbage and carrots that were cleaned, chopped, and mixed with dressing at the individual store.”
According to a Summary of the FDA’s traceback investigation of Hollar & Greene, “The team found that the product contamination could have occurred through several routes. Findings included: Prior to packing, storage and shipping, surface water had the potential to become contaminated from animals; Use of wooden carts for transporting cabbage could cause cross-contamination and Lack of personal hygiene of field workers.”
To appreciate the liability posture of the 1999 case, it was interesting to know that a virtually identical outbreak occurred just a year before. In May 1998 an outbreak of E. coli O157:H7 involving a franchised KFC had occurred in Indianapolis, Indiana. According to the Indiana State Department of Health, in May 1998, two county health departments confirmed four cases of E. coli O157:H7. Eventually, 27 confirmed outbreak-related cases were identified. Food handlers who made coleslaw were interviewed about food preparation and storage procedures:
“Reportedly, a 100-pound batch of coleslaw was made the morning of Tuesday, May 5. Due to the unavailability of cabbage from their regular suppliers, the restaurant obtained cabbage from a different supplier. The cabbage was reportedly of low quality (i.e. had rotten and tom leaves, was “mushy,” and was unusually soiled). Some of the cabbage was discarded due to its poor condition. The outer leaves of the cabbage and the stalks were removed. Although the restaurant’s standard operating procedures for preparing coleslaw called for the heads to be washed after the outer leaves were removed, the food handlers reported that they did not wash it. The unwashed heads were then cut into quarters on cutting boards. A food handler commented that the cutting boards were noticeably soiled with dirt after this process. “
After the 1998 outbreak, according to the Indiana Department of Health, KFC’s “[c]oleslaw preparation practices [were] modified at this establishment to include the use of pre-washed and pre-shredded cabbage rather than whole cabbage.”
In both the May 1998 and July 1999 outbreaks, the E. coli O157:H7 bacteria was introduced into the coleslaw by the use of contaminated, whole cabbage. Following the Indiana outbreak in 1998, KFC required all franchisees to use pre-washed, pre-shredded coleslaw, however, KFC did not institute this rudimentary food safety practice in the restaurants it owned and operated.
This is another it what will be a long – too long – series of outbreak investigations where we have represented consumers in what I hope will be a cautionary tale, and a learning experience, for manufacturers of food.