Virus adhesion to archetypal fomites: A study with human adenovirus and human respiratory syncytial virus

Adhesion of two viruses – one enveloped (human respiratory syncytial virus, HRSV) and one non-enveloped (human adenovirus 5, HAdV5) – to four fomites (silica, nylon, stainless steel, polypropylene) was quantified and interpreted based on physicochemical properties of viruses and fomites. The selected fomites are tentatively identified as “archetypes” representing groups of materials distinctly different in mechanisms of their interfacial interactions. The surfaces are typified on the basis of their surface energy components including the dispersive (Lifshitz-van der Waals) component and two polar (electron donor and electron acceptor) components. Virus-fomite interactions are predicted using the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory and are experimentally assessed in tests with quartz crystal microbalance with dissipation (QCM-D). Polar interactions (manifested as hydrophobic attraction for all virus-fomite pairs but HAdV5/silica) governed virus attachment to fomites from a solution of high ionic strength typical for a respiratory fluid, while dispersive interactions played a relatively minor role. For both HAdV5 and HRSV, the areal mass density of deposited viruses correlated with the free energy of virus-fomite interfacial interaction in water, ΔGvwf. The dependence of virus-fomite attachment probability on ΔGvwf collapsed into one trend for both HAdV5 and HRSV pointing to the possibility of using ΔGvwf as a predictor of virus adhesion. Fomite rinsing with DI water resulted in a partial virus removal attributable to longer range repulsive electrostatic interactions. The proposed methodology can guide screening and selection of materials that discourage virus adhesion. The information on the efficiency of virus attachment to materials as a function of their surface energy components can help design anti-adhesive surfaces, develop surface cleaning solutions and protocols, and inform transport and fate models for viruses in indoor environments.