The Olmsted County Public Health Services Department has traced a salmonella outbreak at a local sub shop in October to tomatoes that were contaminated before they reached the store.
Epidemiologist Larry Edmonson said studies showed the problem didn't start in the Quiznos sandwich store where more than 20 customers and employees were sickened last month.
The store closed for a day to have a cleaning company sterilize its equipment, then reopened.
Doug Schultz, a spokesman for the state Health Department, said the fact that there were no reports of illness at other Rochester restaurants suggests that only the shipment received by that Quiznos was contaminated.
Although the case is now considered closed, he said that since none of the tomatoes were available for laboratory testing it was impossible to be 100 percent sure they were the source of the salmonella.
--- Information from: Post-Bulletin, http://www.postbulletin.com