Food Illness Outbreaks That Cross State Lines Are the Most Deadly

The CDC analyzed data from its Foodborne Disease Outbreak Surveillance System during 2010-2014 for the report.

They found that the 120 multistate outbreaks accounted for 11 percent of illnesses, 34 percent of hospitalizations and 56 percent of deaths.

The CDC is now investigating an outbreak of disease caused by Escherichia coli in Oregon and Washington that has led the Chipotle restaurant chain, implicated in the outbreak, to close many of its outlets in those states.

Salmonella accounted for 82% of cases and 65% of the hospital admissions, while Listeria was the most deadly pathogen, accounting for 86% of the 66 fatalities, including 33 in a single outbreak linked to cantaloupe.

Fruits, vegetables and beef were the biggest carriers of these germs, although Frieden noted that new techniques mean more unusual foods are turning up, such as the contaminated caramel apples that killed seven people last winter.

Frieden said state-of-the-art disease tracking tools, and the introduction of gene tools, are helping to quickly track down the source of food-borne outbreaks. “Food imported from Mexico was the leading source in these outbreaks, followed by food imported from Turkey”, the CDC said.

The CDC said the report sheds light on a larger safety role for food companies-for example, following best practices for growing, processing, and shipping, keeping detailed records to help trace foods from source to destination, using store loyalty cards to help identify contaminated foods during outbreaks, and notifying customers of food recalls.

But researchers believe more people are dying in the multi-state outbreaks because the infections are deadlier. Salmonella (63 outbreaks), Shiga toxin-producing E. coli (34), and Listeria monocytogenes (12) were the leading pathogens.

“Americans should not have to worry about getting sick from the food they eat“, said CDC Director Tom Frieden, MD.

Federal health officials said today that their agencies are taking more steps to improve food safety, driven by implementation of the 2011 Food Safety Modernization Act. Only 3 percent of all reported outbreaks of foodborne illness crossed state lines, but they caused 7 percent of the illnesses – almost 8,000 out of more than 71,000 reported illnesses.

Craig Hedberg, PhD, a food safety expert in the University of Minnesota’s School of Public Health, told CIDRAP News that multistate outbreaks are clearly very important, but he raised issues with how the CDC compared the two types of outbreaks. So far, officials say, they’ve been able to solve a few “cold cases” by finding contaminated food responsible for unsolved illnesses. Imported foods were linked to 18 multistate outbreaks.

Although bacteria are more likely to contaminate foods like beef, chicken, and fresh fruits and vegetables, health officials have also seen the unexpected contamination of certain foods.

But Frieden said rapid detection of outbreaks, combined with advanced genetic methods of tracing the pathogen, can slow their spread and help prevent further illness.