New York, Sep. 7 - Four large multistate outbreaks of Salmonella infections occurred in 2005 and 2006, affecting Canada and 21 states in the US. Researchers determined that at least 459 culture-confirmed cases of salmonella infection were caused by raw tomatoes eaten in restaurants, with up to 35 percent of those affected requiring hospitalization.
Staff members at local and state public health departments, the Food and Drug Administration, and the Centers for Disease Control and Prevention (CDC) determined the characteristics of the outbreaks, which they report in Friday's edition of the CDC publication, Morbidity and Mortality Weekly Report.
Case-control studies conducted during each outbreak verified that the infections were indeed caused by eating raw tomatoes at restaurants.
"The outbreaks described were widely dispersed, indicating that contamination occurred early in the distribution chain, such as at the farm or packinghouse, rather than in restaurants," CDC investigators pointed out.
Since 2002, clusters of infection with one particular strain of Salmonella have been detected each year, the authors add. "These recurrent multistate outbreaks indicate that the tomato-growing environment is an ongoing source of contamination of tomatoes."
Their diligence revealed that the contaminated tomatoes originated from fields in Florida, Ohio and Virginia.
"Growers, harvesters, repackers, retailers, and food service employees should follow guidelines for good manufacturing practices and good agricultural practices when handling tomatoes," the authors advise.
Consumers, they add, should not purchase or eat tomatoes that are bruised, damaged, or spoiled. Cut, peeled, or cooked tomatoes should be refrigerated within 2 hours, and need to be stored away from other raw produce, raw meat and seafood.