New York, 10 Dec - Improperly cooked frozen pot pies are to blame for an outbreak of salmonella infections across dozens of U.S. states last year, according to health officials.
The outbreak, which sickened 401 people, highlights the importance of thoroughly cooking microwavable, not-ready-to-eat frozen foods, says the U.S. Centers for Disease Control and Prevention (CDC). Individuals in 41 states developed salmonellosis and 32 percent of those affected were hospitalized.
Salmonella bacteria are a common cause of foodborne illness. Symptoms include diarrhea, abdominal cramping and fever within 12 to 72 hours of eating contaminated food.
CDC investigators were able to link the 2007 outbreak to Banquet-brand frozen, microwavable pot pies. Three quarters of the 236 victims who were interviewed said they had eaten the product the week before becoming ill, the researchers report in the CDC's Morbidity and Mortality Weekly Report.
Because not-ready-to-eat frozen foods contain some raw ingredients, they must be thoroughly cooked in order to kill any Salmonella bacteria that might be present.
The CDC investigation found that most consumers who were sickened during the outbreak had microwaved the culprit pies, and confusion over the package cooking instructions might have played a role in the outbreak, the agency says.
For example, investigators found, different parts of the package recommended different cooking times. In addition, the cooking times varied according to microwave wattage, and most consumers who were asked did not know the wattage of their microwave.
After issuing a voluntary recall of the implicated products, manufacturer ConAgra Foods changed the labeling to make the microwaving instructions more clear.
Other frozen foods have been linked to Salmonella outbreaks in the past, the CDC points out. To reduce the risk, the agency advises consumers to follow the cooking instructions for their specific microwave wattage, and to always cook the product as recommended.
A number of patients in this latest outbreak said they did not let the product stand after microwaving, as recommended on the labeling.
Several others said they microwaved more than one pie at a time, which would have kept them from cooking fully.