Effects of Ozone Treatment on Personal Protective Equipment Contaminated with SARS-CoV-2

Abstract

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is causing profound health, economic, and social problems worldwide. Management of personal protective equipment (PPE) and its potential limited availability have created concerns about the increased risks for healthcare professionals at hospitals and nursing homes. Ozone is a powerful oxidant agent. The objectives of this study were to examine the effects of ozone treatment on PPE contaminated with SARS-CoV-2, and to explore whether relative humidity could modify those effects. Methods: PPE contaminated by heat-inactivated SARS-CoV-2 were treated with different ozone concentrations, exposure times, and relative humidity conditions. SARS-CoV-2 gene amplification was assessed by real-time polymerase chain reaction. Results: There was no amplification of SARS-CoV-2 in PPE after the following ozone exposures: 30 s at 10,000 ppm (20 g/m3), 5 min at 4000 ppm, and 10 min at 2000 ppm. At lower ozone concentrations, 4–12 ppm (0.008–0.024 g/m3), the effects were highly dependent on the relative humidity conditions. Conclusions: Oxidative stress induced by ozone exposure eliminated heat-inactivated SARS-CoV-2 in different PPE components under appropriate exposure times, ozone concentrations, and relative humidity conditions. These findings could have implications in decreasing the risk of contamination associated with personal protective equipment management and in increasing its availability. Further research in the original SARS-CoV-2 strain is guaranteed.

Can ozone inactivate SARS-CoV-2? A review of mechanisms and performance on viruses

“… 4.0 (b.d.) 80 24 ( Blanchard et al, 2020 ) c Rhinovirus 1 A and 14 NO 28 a 60 2.500 glass surface 2.0 40 20 ( Hudson et al, 2009 ) Rhinovirus 1 A and 14 NO 20 a 60 1.800 undetermined 3.0 40-95 room ( Hudson et al, 2009 ) SARS-CoV-2 YES 10000 0.500 9.810 PPE gown b RNA undetected 53-65 22 ( Clavo et al, 2020 ) SARS-CoV-2 YES 4000 0.500 3.924 face mask b RNA undetected 53-65 22 ( Clavo et al, 2020 ) SARS-CoV-2 YES 4-6.5 30 0.324 PPE gown b RNA undetected 99 22 ...…”

“…60-65 m ( Dave et al, 2020 ) Poliovirus PV Picornaviridae NO 2 enteric virus, causative of polio ssRNA (+) 6.7–10.1 kB 30–32 nm icosahedral virions comprising 60 protomers ( Bolton et al, 1982 , Hudson et al, 2009 ) PR772 PR772 Tectiviridae NO 1 phage virus, model for adenovirus linear dsDNA, 15 kb icosahedral virion with a pseudo T=25 symmetry.66-80 nm with apical spikes of 20 nm. ( Dubuis et al, 2020 ) Reo type 3 virus RT3 reoviridae NO 1 dsRNA virus, 18.2-30.5 kB icosahedral virion, multilayer capsid structure, 60-80 nm ( Sato et al, 1990 ) Respiratory syncytial virus A2 RSV Pneumoviridae YES 1 human pathogen ssRNA (-) 13-15 kB spherical and filamentous virions, 150 nm ( Blanchard et al, 2020 ) Rhinovirus types 1 A & 14 RV Picornaviridae NO 1 Common cold virus, enterovirus ssRNA (+) 6.7–10.1 kB 30–32 nm icosahedral virions comprising 60 protomers ( Hudson et al, 2009 ) SARS-CoV-2 coronaviridiae YES 2 COVID19 responsible ssRNA (+), 29.9 kB spherical, some pleomorphism, 60-140 nm ( Clavo et al, 2020 ), ( Yano et al, 2020 ) Sendai virus HVJ Paramyxoviridae yes 1 representative respirovirus ssRNA (-) virus 15 kb pleomorphic, but usually spherical or filamentous, >150 nm ( …”

“…Regarding the virus experimentally tested and gathered in Table 3 , it is worth noting that at the time this review was written there were already two publications in which ozone was tested against the responsible agent for current pandemic, that is, SARS-CoV-2 and it was proven effective ( Clavo et al, 2020 , Yano et al, 2020 ). Furthermore, there were also three works ( Blanchard et al, 2020 , Hudson et al, 2009 , Lee et al, 2020 ) which proposed 4 different surrogates for this species (influenza A virus, respiratory syncytial virus, murine coronavirus and HCoV-229E) against which ozone was again operative.…”

“…At the time this publication was submitted, only two very recent, concise works were found in literature where O 3 was applied for the disinfection of SARS-CoV-2 ( Clavo et al, 2020 , Yano et al, 2020 ). Also, a paper reviewing the use of ozone for indoor air treatment against viruses was published ( Alimohammadi and Naderi, 2020 ).…”

The viability of SARS-CoV-2 on solid surfaces

“…SARS-CoV-2 can be inactivated by other methods, such as light-activated coatings[ 62 ], ultraviolet (UV) light [ [63] , [64] , [65] ], atmospheric cold plasma [ 12 ], heat treatment [ 66 ], and ozone [ 67 ].…”