Purpose: We investigated the effectiveness of UV-C radiation (10–300 mWs/cm2) in controlling the infectivity of NoV, using murine norovirus-1 (MNV-1) and an HAV on a stainless steel surface that could be a major source of cross-contamination and foodborne enteric viruses and was to compare reduction responses of the viruses on the UV-C treated surface.
Methods: Stainless steel surface was used to examine the effects of low doses of UV-C radiation on MNV-1 and HAV titers (initial, approx. 5 log PFU of MNV-1 or HAV). The Weibull model was used to determine decimal reduction value (dR-values, 90% reduction) of UV-C dose against MNV-1 or HAV.
Results: The Weibull model was used to generate non-linear survival curves and calculate dR-values for MNV-1 (R2 = 0.91) and HAV (R2 = 0.95). Total MNV-1 and HAV titers significantly decreased (P < 0.05) with higher doses of UV-C (10–300 mWs/cm2). MNV-1 and HAV were reduced to 0.03–4.43 and 0.03–2.62 log PFU/ml, respectively, on the stainless steel surfaces by low-dose UV-C treatment. The dR-value for MNV-1 (35.85 mWs/cm2) was significantly (P < 0.05) lower than that of HAV (53.94 mWs/cm2) after UV-C treatment. Therefore, this study shows that HAV is more resistant to UV-C radiation than MNV-1.
Significance: This study suggests that low doses of UV-C light on food contact surfaces could be effective to inactivate human NoV and HAV in restaurant, institutional, and industrial kitchens and facilities.