Poultry caused about 19 percent of foodborne fatalities in the 10-year period through 2008, the CDC said Tuesday in a study that marks the first time the Atlanta-based agency has estimated how many illnesses may be attributed to specific foods. Dairy accounted for 10 percent of deaths and vine-stalk vegetables such as peppers were responsible for 7 percent.
While fatalities are more common with meat, leaf vegetables such as spinach caused more illnesses than any other product and the second-most hospitalizations after dairy. Large outbreaks during the period studied include E.coli traced to spinach and lettuce, and salmonella in tomatoes and peppers. The CDC said the findings show a need to focus more on preventing contamination of produce and poultry.
"Food regulators and industry have to make decisions about where to put their resources," Patricia Griffin, chief of the CDC's enteric diseases epidemiology branch, said in an interview. "A lot of times you never know what food makes you sick."
The study, published in the agency's Emerging Infectious Diseases journal, looked at outbreaks from 1998 to 2008 that caused deaths, hospitalizations and illnesses after consumers ate 17 common food products. Contaminated food causes an estimated 48 million illnesses each year, with only about 9.6 million of those traced to known major pathogens lurking in food. The study examined a subset of known-pathogen illness.
Of the 277 deaths from poultry, most came from listeria or salmonella, two bacteria that cause diarrhea and other symptoms. Pregnant women, babies, and the elderly are among those at increased risk. Listeria can be more deadly than some other types of contaminants, Griffin said.
The number of deaths from poultry is partly tied to three outbreaks from delicatessen turkey meat tainted during processing after the product was cooked, according to the report. That may also have skewed the data to indicating poultry is more risky, Griffin said.
"The data suggest deli meat is a lot safer today," she said.
Illnesses from produce were largely driven by norovirus, which is highly contagious and causes diarrhea, vomiting and stomach pain. Norovirus caused 1,419 outbreaks, which was the most of all pathogens, the study said. It can get into food when preparers don't wash their hands, according to the CDC.
"Many leaf green outbreaks are caused by norovirus, and it can only be people, not animals, so it could be from not washing their hands," Griffin said.
Dairy caused the most hospitalizations at 16 percent, and botched pasteurization and contamination after pasteurization were potential causes. Dairy may be a more frequent cause of illness because of a high number of outbreaks from consumers who drink raw milk, according to the report.
"Because of the large volume of dairy products consumed, even infrequent contamination of commercial distributed products may result in many illnesses," the authors said in the report.