Virucidal efficacy of gaseous chlorine dioxide against surface-dried Adenovirus and Herpesvirus

Virucidal efficacy of gaseous chlorine dioxide against surface-dried Adenovirus and Herpesvirus

Chlorine dioxide (ClO₂) has recently emerged as an ideal disinfectant and has shown a wide range of antimicrobial activities in various pathogenic microorganisms. In this study, the virucidal effect of ClO₂ at low concentration (0.02 ppm) and higher concentration (0.06 - 0.09 ppm) against Adenovirus and Herpesvirus was evaluated based on the NF T 72-281 and ASTM 1053-11 standard methods at different exposure times. The virus suspension was dried onto the carrier and then exposed to gaseous ClO₂ (gClO₂) at 22 ± 2℃. For Adenovirus, exposure at a low concentration of ClO₂ at the middle height resulted in the average log10 reduction of 0.95, 2.65, and 5.30 after 1, 3, and 6 h post-exposure (pe), respectively. Moreover, more than 4-log10 reduction was achieved at 4 and 6 h pe with higher concentrations of ClO₂. On the other hand, the antiviral activity of gClO₂ at the middle height was also effective against Herpesvirus. In particular, at 1 h pe, a less than 4-log10 reduction was observed at all examined concentrations of ClO₂, whereas exposure for 3 and 6 h (with low concentration) or 2 h (with higher concentration) inactivated completely viruses attached to the carrier. These results suggested that ClO₂ fumigation is a potential alternative method for disinfecting healthcare facilities, high-containment laboratories, and households with a safe concentration for human health.