On August 22, 2000, Marion County Health Department (MCHD) investigators contacted the Oregon Health Department to report that a number of county residents were suffering from E. coli O157:H7 infections.
MCHD conducted a case-control study to determine the source of the apparent E. coli outbreak and quickly learned that several cases had eaten at a Wendy’s restaurant located at 2375 Commercial St. SE in Salem. Pulsed field gel electrophoresis was conducted on E. coli isolates from patients’ stool specimens, and the PFGE pattern, or DNA fingerprint, obtained confirmed the epidemiologic link between case-patients, including one victim whose only exposure to Wendy’s was a restaurant in Tulatin, Oregon.
The health department investigation revealed that cross contamination from contaminated ground beef may have been the outbreak source, as a number of victims had not eaten ground beef products. Marion County Inspectors found several food-handling problems that likely resulted in cross-contamination, causing E. coli bacteria in the meat to contaminate other foods. These included:
- Food-preparation staff soaked lettuce in the first compartment of a three-compartment sink that was used to rinse bloody meat-juice-covered pans in which raw hamburger patties had been held, without cleaning and sanitizing the sink between uses.
- Food-preparation staff used a cleaning and sanitizing “wet towel, dry towel” process, whereby a shelf above the grill that held raw hamburger patties was wiped clean first with a dry towel, then with a sanitized-soaked wet towel. The dry, bloody meat-juice-soaked towel was used for hand wiping in both the grill area and the sandwich assembly area (where raw products are placed on cooked burgers).
- Poor hand washing was observed.
MCHD concluded that cross-contamination occurred between the meat that was supplied to both the Salem and Tualatin Wendy’s Restaurants and other food items that did not undergo a further “kill step.”
Marler Clark represented fifteen victims of the Wendy’s E. coli outbreak in claims against the restaurant chain. The claims were resolved in late 2001 and early 2002.