Fate and transport of enveloped viruses in indoor built spaces - through understanding vaccinia virus and surface interactions.

The current coronavirus disease 2019 (COVID-19) pandemic has reinforced the necessity of understanding and establishing baseline information on the fate and transport mechanisms of viruses under indoor environmental conditions. Mechanisms governing virus interactions in built spaces have thus far been established based on our knowledge on the interaction of inorganic particles in indoor spaces and do not include characteristics specific to viruses. Studies have explored the biological and kinetic processes of microbes' attachments on surfaces in other fields but not in the built environment. There is also extensive literature on the influence of indoor architecture on air flow, temperature profiles, and forces influencing aerosol transport. Bridging the gap between these fields will lead to the generation of novel frameworks, methodologies and know-how that can identify undiscovered pathways taken by viruses and other microbes in the built environment. Our study summarizes the assessment of the influence of surface properties on the adhesion kinetics of vaccinia virus on gold, silica, glass, and stainless-steel surfaces. We found that on gold the virus layer was more viscoelastic compared to stainless-steel. There was negligible removal of the layer from the stainless-steel surface compared to the others. The results further highlight the importance of converging different fields of research to assess the fate and transport of microbes in indoor built spaces.