LAUSR

Blue light has been already reported as able to counteract different types of microorganisms including Gram‐positive and Gram‐negative bacteria, fungi and viruses, especially the enveloped ones. It has been reported that both blue and visible light can efficiently impact SARS‐CoV‐2 by affecting its ability to replicate in in vitro cellular models of infection. In this study, blue light at 450, 454 and 470 nm was tested on SARS‐CoV‐2 to evaluate the residual viral infectious potential on Vero E6, Caco‐2 and Calu‐3 cells, after the irradiation of viral particles. Following 12' of irradiation at 40 mW/cm2, a drastic block of viral amplification was observed. Indeed, at 7 days post‐irradiation/infection the viral load was the same as the one measured 1 day post‐irradiation/infection, and cellular viability was maintained showing similar levels to the noninfected control cells. Taken together our results indicate that blue LED lamps can be considered as a cheap and convenient tool for SARS‐CoV‐2 disinfection.