The agency’s latest report detailing foodborne illness outbreaks, entitled "Surveillance for Foodborne Disease Outbreaks — United States, 2007", and outlined in its Mortality and Morbidity Weekly Report, said that there were 1,097 reported outbreaks in 2007, resulting in 21,244 illnesses and 18 deaths. Poultry was the number one cause of illness for the 235 outbreaks for which a single food source was identified, accounting for 17 percent of those reported, closely followed by beef, at 16 percent and leafy greens, at 14 percent.
However, these figures likely represent just the tip of the iceberg in terms of the actual number of people who get food poisoning over the course of a year, according to the CDC. It estimates that about 76m people suffer from foodborne illness each year in the United States, including 375,000 hospitalizations and about 5,000 deaths – but only a tiny percentage of those are linked to a reported outbreak.
Acting director of the CDC's Division of Foodborne, Waterborne and Environmental Diseases Chris Braden said: "Knowing more about what types of foods and foodborne agents have caused outbreaks can help guide public health and the food industry in developing measures to effectively control and prevent infections and help people stay healthy.”
Norovirus, usually spread by inadequate hand washing after food handlers use the toilet, caused 39 percent of illnesses identified as coming from a single source, while salmonella bacteria, spread in animal feces, accounted for 27 percent.
The CDC collated data from 48 states and Puerto Rico for the report.
The most common reasons for not identifying a particular cause of illness or food were delayed reporting to the health department; too many foods consumed by the ill person to identify a single source; and lack of availability of human and food sample tests, the CDC said.