Project Summary More than a million of Healthcare-Associated Infections (HAI) occur in the US every year. HAIs affect about one in 30 patients, which makes them the leading risk for morbidity and mortality associated with medical care. Transmission of the infections occurs thorough various routs, with about 30% of transmissions occurring through frequently touched surfaces, such as door handles, elevator buttons, light switches, etc. This, frequently touched surfaces in healthcare settings require regular and thorough cleaning and disinfection. The use of commercially available disinfectants significantly reduces microbial counts on environmental surfaces for only up to 4 hours after treatment. An alcohol-based disinfectant with a compound capable of forming a durable biocidal film that could slowly release an antimicrobial active ingredient could combine high short-term efficacy due to the presence of alcohol and prevent microbial re-contamination due to the long-lasting efficacy of the film, while requiring less frequent applications. VRM Labs has recently developed such disinfectant, which contains 3 wt. % chitosan, 60 % wt. ethanol, and a natural active antimicrobial, sandalwood seed oil. Chitosan is obtained from crustacean shells and its antimicrobial and antiviral efficacy is well-established. However, it has not been used in surface disinfectants because of high viscosity of its aqueous solutions and long drying times required to form a continuous film. Our proposed formulation has low viscosity, outstanding film-forming properties and drying time similar to that for currently used disinfectants. During the Phase I study, frequently touched surfaces treated by this novel formulation completely prevented microbial growth for up to 72 hours after treatment. This natural formulation outperformed currently available synthetic disinfectant Microban24 which showed 24 h compete protection in the same trial. The goal of the proposed Phase II grant is to collect comprehensive data required for regulatory approval and customer acceptance of this product and develop scaled up manufacturing to make this product commercialization ready. During the proposed study, we will optimize the composition of the formulation (Aim I) and perform comprehensive toxicity and efficacy studies required for the regulatory approval (Aim II). We will also perform a multi-site filed study of the efficacy of our product on frequently touched environmental surfaces in two hospitals in the Midwest (Cleveland Clinic, OH) and in the Southeast (Prisma Health, SC) (Aim III). Finally, we will undertake a scaling up in collaboration with the largest domestic chitosan manufacturer, Tidal Vision USA.