A new route of transmission for Escherichia coli: infection from dry fermented salami.

Objectives: This study evaluated the production of dry fermented salami associated with an outbreak of Escherichia coli O157.H7 infection in Washington State and California.

Methods: Facility inspections, review of plant monitoring data, food handler interviews, and microbiological testing of salami products were conducted.

Results: Production methods complied with federal requirements and industry-developed good manufacturing practices. No evidence suggested that postprocessing contamination occurred. Calculations suggested that the infectious dose was smaller than 50 E. coli O157:H7 bacteria.

Conclusions: Dry fermented salami can serve as a vehicle of transmission for O157:H7 strains. Our investigation and prior laboratory studies suggest that E. coli O157:H7 can survive currently accepted processing methods.