Evaluating the Effect of Coated Filters and Prefilters on the Infectivity and Concentration of Aerosolized Phi6 Virus

Development of efficient indoor air filtration technologies has gained prominence during the COVID-19 pandemic. This study investigated the antiviral effect of various copper and silver-based surface coatings for air filters which were tested in an aerosol chamber using the enveloped model bacteriophage Phi6. Some copper and silver-based surface coatings were shown to fully inactivate Phi6 viruses in up to 15 min. However, when filter and prefilter materials were coated with the chosen antiviral surface material their properties did not differ significantly from uncoated filters or prefilters in aerosol chamber tests, mainly due to uncoated filters already featuring an extremely high efficiency in filtering viral particles from the air. When coated filters were used in purifying systems for three months in populated environments, an improved filter capacity was observed, indicating persistence of the antiviral efficiency.