Poultry, leafy vegetables, fruits, and nuts were the main drivers of food borne disease in 2006, according to the Centre for Disease Control and Prevention in the United States.
That year, the most recent for which detailed information is available, there were 1,270 food borne disease outbreaks (>2 cases) accounting for 27,634 cases and 11 deaths, CDC researchers reported in the June 12 issue of Morbidity and Mortality Weekly Report.
Among outbreaks that were attributed to a single food, poultry was blamed for 21%, followed by leafy vegetables (17%) and fruits and nuts (16%).
After a concerted campaign by the federal Department of Agriculture to improve the safety of chickens, the number of people sickened by contaminated poultry in 2006 declined compared with an average of the previous five years, according to C.D.C. researchers.
But problems persist. Most of the poultry-related illnesses, the centres found, were associated with Clostridium perfringens.
The spores from this bacterium often survive cooking, so keeping poultry meat at temperatures low enough to prevent contamination during processing and storage is critical.
Researchers counted leafy vegetables, fungi, root vegetables, sprouts and vegetables from vines or stalks as separate categories.
If all of the produce categories were combined, outbreaks associated with vegetables would have far exceeded those in poultry.
Norovirus and salmonella
While poultry is the most common source of illnesses among the 17 different foods tracked by federal officials, the CDC found that two-thirds of all food-related illnesses traced to a lone ingredient were caused by viruses.
These are often added to food by restaurant workers who fail to wash their hands. Such viruses often cause what many people refer to as a stomach flu.
Among outbreaks with a single cause, norovirus accounted for 54% and Salmonella accounted for 18%.
The 2006 data came from the Foodborne Disease Outbreak Surveillance System, which collects reports from state and local health departments.