Norovirus is highly infective, as only a low dose is needed to cause disease. Infection occurs from contact with infected people, food, water, or environments. Because the virus cannot be grown in vitro, evaluating efficacy of various disinfectants has been difficult. This virus is related to feline calicivirus (FCV), however, and FCV is a suitable alternative for testing of disinfectants. In this study, surfaces were contaminated with FCV, allowed to dry, and then treated for 10 minutes with a quaternary ammonium compound (QAC) disinfectant that included dialky dimethyl ammonium chloride and appropriate controls, including 100 and 1000 ppm sodium hypochlorite solutions. After the 10 minutes, complete inactivation of the FCV on hard surfaces was achieved by the QAC. Previous studies have shown that QAC-based disinfectants are not efficacious against norovirus or FCV. However, the manufacturer of this product hypothesizes that the unique QAC combination and the high alkaline pH is what makes the product so effective. Pilot studies in this paper revealed that a contact time of 10 minutes vs 5 minutes and a dilution of 1:256 were very effective in inactivating FCV in the presence of 5% organic soil. This product is considered a one-step disinfectant in that it cleans and disinfectants in one application. However, it is important to note that a wetting contact time of 10 minutes is needed. Study funded by the manufacturer, Lonza Inc, Allendale, NJ
COMMENTARY: Although the goal of the study was to produce data to get label claim for norovirus, an unexpected benefit was an investigation on the use of QAC for disinfecting hard surface areas exposed to FCV. Most cleaning protocols include a 2-step process: cleaning to remove organic debris followed by disinfection. Bleach is commonly used as a disinfectant for FCV, and this study again shows that it is very effective. This product, marketed as Lonza R-82 Formulation 1:256, may be of interest to veterinarians and people working in shelters because it is a one-step cleaning product. It received EPA approval in March 2000.
Virucidal activity of a quaternary ammonium compound disinfectant against feline calicivirus: A surrogate for norovirus. Jimenez L, Chiang M. Am J Infect Control 34: 269-273, 2006.