Commercial Sanitizers Lack Efficacy Against Norovirus

Article By Adrienne Blume Published September 14, 2022
Article Source: Commercial Sanitizers Lack Efficacy Against Norovirus | Food Safety (food-safety.com)

A recent study published in Applied and Environmental Microbiology, titled, "The Efficacy of Commercial Surface Sanitizers against Norovirus on Formica Surfaces with and without Inclusion of a Wiping Step," evaluated four commercial disinfectants that are listed by the U.S. Environmental Protection Agency (EPA) as being "active" against norovirus, the leading cause of acute gastroenteritis and foodborne illness worldwide. The study found that three of the disinfectants did not work well against the virus. The fourth however, was found to be very effective at killing norovirus.

The study specifically looked at the use of commercial sanitizers on Formica surfaces (commonly used in restaurant tabletops), with and without the inclusion of a newly developed wiping application step. The study notes that the impact of inactivation versus removal when the sanitizers were applied via wiping is poorly characterized. 

Four commercially available products with different active ingredients (i.e., ethanol, acid plus anionic surfactant [AAS], quaternary ammonium compound [QAC], and sodium hypochlorite [NaOCl]), and a water control, were evaluated against norovirus GII.4 Sydney, norovirus GI.6, and the surrogate Tulane virus. Only the ethanol-based product significantly reduced virus concentration (> 3.5 log reduction) by surface assay, with all other products resulting in ≤ 0.5 log reduction. 

The inclusion of a wiping step was found to enhance the efficacy of all four products. Wiping resulted in complete virus elimination for the ethanol-based product, as well as log reductions of 1.6 to 3.8 for the other sanitizers. No detectable residual virus was recovered from paper towels used to wipe the ethanol-based product, although high concentrations of virus were recovered from the used paper towel and the wiped coupon for the QAC- and AAS-based products and for the water control. 

The results highlight the variability in efficacy against norovirus of commercial surface sanitizers and underline the value of the wiping step, which physically removes surface microbes. However, the authors note that there is a need for more and better product formulations with demonstrated efficacy against human norovirus to avoid the risk of contamination and transmission in foodservice facilities.