Human norovirus (HuNoV) is considered an important cause of foodborne outbreaks, often attributed to the preparation of fresh produce by... Show moreHuman norovirus (HuNoV) is considered an important cause of foodborne outbreaks, often attributed to the preparation of fresh produce by infected food handlers. In this investigation, methods for recovery of murine norovirus (MNV-1), a surrogate for HuNoV, from food preparatory surfaces were optimized, and MNV-1 crosscontamination between various surfaces common in a food service setting were studied. Fifty microliters of MNV-1 was inoculated onto demarcated 1 x 1 inch squares of polypropylene cutting board, stainless steel knife and spigots. After drying, MNV-1 was recovered from each surface using either a cotton swab, composite tissue or sterile sponge in combination with different eluents such as tissue culture growth medium, 3% beef extract, glycine buffer (50mM glycine, 1% beef extract), stripping solution (0.04% K2HPO4, 1.01% Na2HPO4, 0.1% Triton X-100), and Earle’s Balanced Salt Solution (EBSS). The eluent/recovery tool combinations that recovered the highest percentage of MNV-1 from cutting board were stripping solution/sponge (20%) and growth medium/swab (20%). The greatest recovery from the knife blade was achieved with the growth medium/composite tissue combination (43%), while recovery from spigots was greatest using the stripping solution/sponge (28%) and the growth medium/sponge combinations (27%). In the second phase of this investigation, human volunteers were asked to perform various tasks in order to quantify the amount of MNV-1 cross contamination between various surfaces, including bare hands, fresh-cut lettuce, and spigots. The percentage of MNV-1 transfer from hands to spigots varied from 0.06% to 3.59%, spigots to hands varied from 10% to 90.4% and lettuce to hands varied from 0.30% to 4.33%. x The results of this investigation can be used in developing a model describing the transfer pattern of HuNoV between surfaces common in retail food service, and used in developing educational materials for food service workers. M.S. in Science, Food Safety, and Technology, December 2011 Show less
