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Society for Risk Analysis Presents Several Studies on the Continued Threat of Foodborne Illnesses

Oct. 2017

Although the quality and safety of food produced and sold in the U.S. remains high, outbreaks of foodborne illness continue to occur. Risk assessments are needed to better monitor and control foodborne pathogens. Measuring the risk of foodborne illnesses, along with the burden associated with them, helps the public understand their impact and could inform public policy and regulations.

Fourteen studies from universities, the U.S. Food and Drug Administration (FDA) and the U.S. Department of Agriculture (USDA) exploring risks associated with foodborne illnesses and public health regulations will be presented at the 2017 Society for Risk Analysis (SRA) Annual Meeting. 

Preventing foodborne illness remains a top priority for public health agencies. There are several factors that affect how often foodborne illness occur. Specifically, it is important to understand how individual food handling practices contribute to the incidence of foodborne illnesses. Researchers from the FDA will discuss the Food Handling Practices Model (FHPM). 

According to the researchers, the top five factors leading to foodborne illness are: inappropriate behavior related to cooling, thawing, cold holding, advance preparation and hot holding. Safety interventions relating to these five practices could greatly reduce how often foodborne illness occurs. 

Food workers infected with norovirus pose a health threat to consumers through direct and indirect contact with food and surfaces throughout restaurants. FDA researchers evaluated the risk consumers face when ill or recently ill employees return to work either after their symptoms have ended or before they have ended. The results provide insights for developing strategies to limit norovirus transmission in retail food establishments. 

Another article, from the USDA, presents a foodborne illness risk ranking that factors in consumption rates for eight major animal product food categories and 28 fruit and vegetable categories. The rankings show that some products, like milk or beef, which are associated with a large number of foodborne illnesses turn out to have a relatively low risk per serving, while other products, like fish & shellfish or chili peppers, which are not associated with as many foodborne illnesses have a relatively high risk per serving. 

As a whole, leafy greens are particularly susceptible to contamination with bacteria such as Listeria, Salmonella and E. coli. Researchers have developed a model to maximize quality and safety of leafy greens. This model can help predict optimal storage temperatures to prevent foodborne illnesses. 

Longer average transit times, decaying transportation infrastructure and rapidly increasing food imports are all factors threatening the safety of food and feed supply. Poor practices, such as failure to protect food during transport, to properly refrigerate food and to adequately clean vehicles between loads, increases the risks of contamination. The 2016 Food Safety Modernization Act (FSMA) Sanitary Transportation rule established requirements for those shipping and receiving food. The FDA has examined the costs and benefits of this regulation to estimate the economic impacts. 

Before the 2016 Act, the 2011 FSMA required a study of the transportation of food for human consumption including the unique needs of rural and frontier areas. The researchers found that lack of infrastructure and insufficient employee training had the greatest impact on the safe delivery of foods. 

Another study analyzed a leading consumer packaged goods company’s effort to mitigate food safety concerns during low acid pudding, acid gels and dried milk products production. Researchers applied the principles of Failure Modes, Effects and Criticality Analysis (FMECA), a risk assessment methodology. FMECA was evaluated as a mechanism for continuous improvement in the food production environment and to verify how well preventive controls worked in a manufacturing facility’s food safety plan. The researchers analyzed potential food safety issues occurring at different steps throughout the manufacturing process. The results revealed that the preventive controls implemented in the manufacturing process significantly minimized or prevented food safety hazards.  

Within food manufacturing facilities, the entry and persistence of microbial pathogens can lead to food contamination and cross-contamination, which occurs when bacteria are spread from one place to another. However, the details of cross-contamination are not well understood. Mathematical models provide a cost-effective way to assess the risks of cross-contamination and the effects of risk management strategies. The researchers developed a way to simulate interactions between food handlers, food and objects present in different areas within the facility, as well as cross-contamination.

Results from a case study involving Listeria contamination show that areas where food is not prepared (such as the loading dock, storage areas and restrooms) can become cross-contaminated after food workers spread the bacteria there. This can result in re-contamination of areas where food is being prepared. Ensuring food workers wash their hands and maintain personal hygiene is the best way to avoid spreading microbes.

The USDA has proposed rules aimed at reducing the incidence of Listeria in ready-to-eat meat and poultry products. In the wake of recent product recalls and outbreaks of foodborne listeriosis, the USDA has analyzed whether the final environmental testing requirements reduced the number of meat-related listeriosis illnesses. Although the results show the final testing requirements had no effect, proposed requirements reduced the number of illnesses by roughly 10 per year. 

These studies will be presented during three sessions at the 2017 SRA Annual Meeting at the Crystal Gateway Marriott in Arlington, Virginia. 

Melanie Preve