The objectives have been determined by considering the flow of fresh produce in a typical foodservice operation, and by identifying the most important points for transfer of norovirus (NoV) from humans to food and food preparation surfaces. <UL> <LI>Develop efficient methods to recover and detect human norovirus (HNV) and murine norovirus (MNV-1) from food preparation surfaces by quantitative RT-PCR (qRT-PCR) techniques. <LI>Collect transfer data for MNV-1 between surfaces including knives, cutting boards and stainless steel surfaces common in foodservice procedures used in preparation of fresh produce, and in some cases using co-inoculated HNV and MNV-1, such that MNV-1 data can be used as a surrogate for HNV in the risk assessment. <LI>Collect transfer data for MNV-1 between hands and surfaces common in fresh produce preparation, including an evaluation of the effectiveness of hand washing procedures to prevent or reduce MNV-1 transfer, and evaluation of the effect of gloved vs. ungloved hands on the transfer rate. <LI>Collect spread and transfer data for co-inoculated HNV and MNV-1 from a single produce item to others during a food-preparation process, e.g. salad preparation and mixing, such that MNV-1 data can be used as a surrogate for HNV in the risk assessment. <LI>Calculate appropriate virus transfer and reduction rates, and incorporate this information into a quantitative risk assessment using discrete event simulation modeling software. <LI>Develop educational materials based on research findings and evaluate material effectiveness through onsite food safety observational studies and risk modeling. Research findings will also be disseminated via education programs (including on campus teaching, short courses, seminars, webinars, and presentation of research findings at scientific meetings). <LI>Evaluate the impact of outreach and training methods on behavioral change at the food service establishment level.
NON-TECHNICAL SUMMARY: According to the Centers for Disease Control & Prevention, human enteric viruses are estimated to cause two-thirds of the foodborne illness in the U.S. each year, with the great majority of those attributed to norovirus (NoV). Fruits and vegetables have increasingly been implicated as vehicles for NoV gastroenteritis. Such foods may become contaminated at the source, in a farm setting, during processing, in the home or food service kitchen during preparation, or during serving by infected food handlers or patrons. The goal of this proposal is to examine cross-contamination of NoV during common procedures used in preparation of fresh produce and evaluate the risk reduction after workers' exposure to educational materials developed as a result of the research findings. NoV transfer data will be collected using murine NoV (MNV-1) as a surrogate for human NoV (HNV) between hands, fresh produce items, knives and cutting boards. In some cases, HNV transfer data will also be collected and compared with MNV-1 transfer data. The ability of handwashing and gloves to prevent or reduce virus transfer from hands during food preparation will also be examined. Cross-contamination data generated in this study will be incorporated into a quantitative risk assessment, which may be used to determine risk management strategies that will have an impact on reducing the contamination of fresh produce food items in foodservice settings. Results will be communicated to food safety professionals and foodservice operators, with an evaluation of risk reduction based on behavioral change. <P>APPROACH: A multi-institution team has been assembled consisting of researchers from Illinois Institute of Technology (IIT) National Center for Food Safety and Technology (NCFST) and Rutgers University as well as collaborators from the U.S. Food and Drug Administration (FDA) Center for Food Safety and Applied Nutrition and Ecolab USA. The goal of the proposed study is to examine cross-contamination of norovirus (NoV) during common foodservice procedures used in preparation and service of fresh produce, incorporate NoV transfer data into a quantitative risk assessment, and evaluate the risk reduction after workers exposure to educational materials developed as a result of the research findings. The study will address cross-contamination concerns in the preparation of fresh produce commonly used in salad preparation, using three representative commodities: whole red tomatoes, romaine lettuce and green onions. NoV cross-contamination during the preparation of fresh produce and the transfer of viral particles via human contact to clean produce will be investigated. MNV-1 will be used where direct human contact (via human subjects) is required in the experimental protocol. MNV-1 will also be used to investigate the transfer of viral particles between various environmental and food preparatory surfaces and in some of the experiments the transfer rates will be correlated to that of HNV. The data generated will be incorporated into a quantitative risk assessment, which will be used to develop risk management strategies designed to reduce the contamination of fresh produce food items during foodservice preparation, and the results will be broadly communicated to food safety professionals and foodservice operators, with an evaluation of risk reduction based on behavioral change. The extension proposed in this study will be disseminated via short courses, other educational programs and industry meetings, ensuring both the fresh produce industry and the foodservice industries benefit from this research.