tetano
Editor, Senior Moderator
Am J Infect Control
. 2020 Aug 19;S0196-6553(20)30809-9.
doi: 10.1016/j.ajic.2020.08.022. Online ahead of print.
Effectiveness of 222-nm ultraviolet light on disinfecting SARS-CoV-2 surface contamination
Hiroki Kitagawa[SUP] 1 [/SUP], Toshihito Nomura[SUP] 2 [/SUP], Tanuza Nazmul[SUP] 3 [/SUP], Omori Keitaro[SUP] 4 [/SUP], Norifumi Shigemoto[SUP] 5 [/SUP], Takemasa Sakaguchi[SUP] 3 [/SUP], Hiroki Ohge[SUP] 6 [/SUP]
Affiliations
Abstract
Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), has emerged as a serious threat to human health worldwide. Efficient disinfection of surfaces contaminated with SARS-CoV-2 may help prevent its spread. This study aimed to investigate the in vitro efficacy of 222-nm far-ultraviolet light (UVC) on the disinfection of SARS-CoV-2 surface contamination.
Methods: We investigated the number of viable SARS-CoV-2 after UV irradiation (0.1 mW/cm[SUP]2[/SUP]) at 222 nm for 10-300 s using the 50% tissue culture infectious dose (TCID[SUB]50[/SUB]). In addition, we used quantitative reverse transcription polymerase chain reaction to quantify SARS-CoV-2 RNA under the same conditions.
Results: One and 3 mJ/cm[SUP]2[/SUP] of 222 nm UVC irradiation (0.1 mW/cm[SUP]2[/SUP] for 10 and 30 s) resulted in 88.5 and 99.7% reduction of viable SARS-CoV-2 based on the TCID50 assay, respectively. In contrast, the copy number of SARS-CoV-2 RNA did not change after UVC irradiation even after a 5-min irradiation.
Conclusion: This study shows the efficacy of 222-nm UVC irradiation against SARS-CoV-2 contamination in an in vitro experiment. Further evaluation of the safety and efficacy of 222-nm UVC irradiation in reducing the contamination of real-world surfaces and the potential transmission of SARS-CoV-2 is needed.
Keywords: COVID-19; Disinfection; Environmental contamination; Far-UVC; SARS-CoV-2; Ultraviolet light.
. 2020 Aug 19;S0196-6553(20)30809-9.
doi: 10.1016/j.ajic.2020.08.022. Online ahead of print.
Effectiveness of 222-nm ultraviolet light on disinfecting SARS-CoV-2 surface contamination
Hiroki Kitagawa[SUP] 1 [/SUP], Toshihito Nomura[SUP] 2 [/SUP], Tanuza Nazmul[SUP] 3 [/SUP], Omori Keitaro[SUP] 4 [/SUP], Norifumi Shigemoto[SUP] 5 [/SUP], Takemasa Sakaguchi[SUP] 3 [/SUP], Hiroki Ohge[SUP] 6 [/SUP]
Affiliations
- PMID: 32896604
- DOI: 10.1016/j.ajic.2020.08.022
Abstract
Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), has emerged as a serious threat to human health worldwide. Efficient disinfection of surfaces contaminated with SARS-CoV-2 may help prevent its spread. This study aimed to investigate the in vitro efficacy of 222-nm far-ultraviolet light (UVC) on the disinfection of SARS-CoV-2 surface contamination.
Methods: We investigated the number of viable SARS-CoV-2 after UV irradiation (0.1 mW/cm[SUP]2[/SUP]) at 222 nm for 10-300 s using the 50% tissue culture infectious dose (TCID[SUB]50[/SUB]). In addition, we used quantitative reverse transcription polymerase chain reaction to quantify SARS-CoV-2 RNA under the same conditions.
Results: One and 3 mJ/cm[SUP]2[/SUP] of 222 nm UVC irradiation (0.1 mW/cm[SUP]2[/SUP] for 10 and 30 s) resulted in 88.5 and 99.7% reduction of viable SARS-CoV-2 based on the TCID50 assay, respectively. In contrast, the copy number of SARS-CoV-2 RNA did not change after UVC irradiation even after a 5-min irradiation.
Conclusion: This study shows the efficacy of 222-nm UVC irradiation against SARS-CoV-2 contamination in an in vitro experiment. Further evaluation of the safety and efficacy of 222-nm UVC irradiation in reducing the contamination of real-world surfaces and the potential transmission of SARS-CoV-2 is needed.
Keywords: COVID-19; Disinfection; Environmental contamination; Far-UVC; SARS-CoV-2; Ultraviolet light.