The effect of ultraviolet light treatment on the viability of a SARS surrogate virus (MS2) after aerosolization onto porous and non-porous surfaces

Coronaviruses including SARS-CoV, MERS, and SARS-CoV-2 are highly contagious viruses that cause respiratory illness and can be attributed to over 2,000,000 deaths worldwide (World Health Organization, 2021). Ultraviolet light treatment, as a means of decontaminating surfaces, should be assessed to determine its effectiveness at inactivating the virus so that it may be used to protect those in highly exposed occupations (health care, emergency response, etc.).

The study determined the effectiveness of ultraviolet light treatment on the viability of MS2 virus, a conservative SARS-CoV surrogate, after it has been aerosolized onto surfaces. Eight laboratory trials, four with UV-C light treatment and four without UV-C light treatment, were conducted by aerosolizing the virus onto porous and non-porous surfaces. After aerosolization, a resting period, and UV-C treatment for treated trials, surface samples were taken using foam tipped swabs prewetted in a buffer solution. The swabs were then placed back into the buffer solution and vortexed to remove any viral particles from the swabs. A serial dilution and plaque assay was completed in triplicate for each sample and control to determine viability of each sample.

Surface Concentration of virus was significantly less for UV-C treated surfaces compared to untreated surfaces, showing a 99% reduction in viable MS2, however, there was no significant difference in viability between surface types (p= 0.260). These data suggest that UV-C light treatment is effective at inactivating MS2 on surfaces, and from these data, we can conclude that UV-C light treatment may be effective in inactivating SARS viruses across surface types.