William A. Rutala Research Award: Virucidal Activity of Quaternary Ammonium Compound Formulations Against Feline Calicivirus, a Surrogate of Norovirus

BACKGROUND/OBJECTIVES: Norovirus, formerly known as Norwalk virus, is an important cause of gastroenteritis outbreaks. Infection control practices to eliminate noroviruses from surfaces and environmental samples reduce the morbidity and spread of virus outbreaks. Two different quaternary ammonium compounds formulations were evaluated to determine the virucidal activity against feline calicivirus. METHODS: Since there is no cell culture system for norovirus, feline calicivirus was used as a surrogate in disinfectant studies using hard surface carriers where virus was loaded, dried, and treated with disinfectant solutions. RESULTS: Two quaternary ammonium compound one step disinfectant cleaner formulations, R-82 and 205M-10%, were found to be virucidal after a 10 minute contact time against feline calicivirus (FCV), a surrogate for norovirus, using dilutions of 1:256 in 400 parts per million of hard water and 1:222 in distilled water, respectively, in the presence of 5% organic soil. More than 4 log10 reductions in cytopathic effects of FCV during initial and confirmatory testing, where complete inactivation of the virus occurred at all dilutions tested were obtained, compared to plate recovery control. CONCLUSIONS: Because of their virucidal activity, these two formulations provide an additional tool for infection control practitioners to optimize virus reduction from hard surfaces in hospitals, schools, correctional facilities, cruise ships, and nursing homes. Effective disinfection of contaminated surfaces provides efficacious control of virus outbreaks reducing the potential for norovirus transmission.