Ethanol Inactivates Feline Calicivirus and Murine Norovirus, as Human Norovirus Surrogates on Stainless Steel Surfaces

Ethanol is a popular agent for preventing cross-contamination with human norovirus (NoV) on stainless steel (STS) surfaces that are used for food preparation and manufacture. A polynomial equation was used to evaluate the anti-viral efficacy of ethanol by feline calicivirus (FCV) and murine norovirus (MNV) as NoV surrogates. The level of FCV VR-782 and MNV on stainless steel surfaces were measured at room temperature over 24 h posttreatment with various concentrations (0-70%) of ethanol for different treatment times (0-10 mins). The amount of FCV and MNV that survived on STS after 24 h were 1.60 +/- 0.01 and 1.23 +/- 0.04 log TCID50/coupon, respectively. FCV and MNV had a higher resistance to STS surfaces than Escherichia call, which was used as a representative comparative pathogenic bacterium. The polynomial equations predicting the inactivation of FCV and MNV were as follows: FCV (log TCID50/coupon)= +0.19379+0.067282x(1)+ 0.058945x(2)-8.57143E-004x(1)x(2)-1.44483E-003x(1)(2)-3.51935E-004x(2)(2) (x(1): time and x(2): concentration); and MNV (log TCID50/coupon)=+1.08790+0.65635x(1)+0.077860x(2)-1.47143E-003x(1)x(2)-0.024552x(1)(2)- 6.56158E-004 x(2)(2) (x(1): time and x(2): concentration). Therefore, these polynomial equation models for reduction of FCV and MNV could be used to predict the minimum concentration of ethanol and exposure time required to control human NoV on food contact surfaces.