Ozone for Inactivation of Aerosolized Bacteriophages

Abstract

Because of increasing incidence of virus-containing aerosols, ozone was potentially considered to be a promising method to inactivate airborne viruses. In this investigation, bacteriophages MS2, phi X174, phi 6, and T7 are under evaluation. The effects of ozone concentration, contact time, different capsid architecture of virus and relative humidity (RH) on inactivating airborne viruses by ozone were evaluated in a laboratory test chamber. It was observed that the survival fraction of airborne virus decreased exponentially with increasing ozone dose. Airborne viruses required ozone doses of 0.34 to 1.98 and 0.80 to 4.19 min-mg/m 3 for 90% and 99% inactivation, respectively. For all four tested, the ozone dose for 99% inactivation was 2 times higher than that for 90% inactivation. At airborne phase with a short contact time, viruses with more complex capsid architectures were observed to be less susceptible to ozone inactivation than those with simple ones. For all tested viruses at the same inactivation, the required ozone concentration at 85% RH was lower than that at 55% RH, possibly because the generation of more radicals from ozone reacting with water vapor at the higher RH. In summary, it was concluded that ozone is highly effective for the inactivation of airborne virus.

Quantification of Airborne Influenza and Avian Influenza Virus in a Wet Poultry Market using a Filter/Real-time qPCR Method

“…For cell-type bacteria, filtered E. coli cells were found to lose more than 70% of the colony after 1 h storage (Li and Lin 2001). Because a virus is more fragile than E. coli and yeast in terms of sampling stress in different samplers and inactivation by ultraviolet germicidal irradiation and ozone (Tseng and Li 2005a;Tseng and Li 2005b;Tseng and Li 2006), the effect of storage on filtered virus analyzed using the culture method should be much stronger than on virus analyzed using real-time qPCR. Therefore, the filter/real-time qPCR technique should successfully detect and quantify airborne influenza virus in field studies.…”

Controlling Indoor Bioaerosols Using a Hybrid System of Ozone and Catalysts

“…Wang (2003) found that low concentrations of ozone have high germicidal efficacy against Escherichia coli bioaerosols, but low germicidal efficacy for yeast bioaerosols in chamber studies. Klánová and Lajcíková (2005) indicated that the levels of Escherichia coli and Pseudomonas aeruginosa bioaerosols decreased to undetectable levels following ozone treatment for 12 h. Tseng (2006) found that ozone is highly effective in disinfecting four airborne viruses; however, viruses are generally difficult to treat with ozone because of their more complex capsid architectures and short contact time.…”

“…Many aerobiological technologies have been developed to control indoor bioaerosols: ventilation, filtration, ultraviolet germicidal irradiation, photocatalytic oxidation, ionization, ozone, negative ion, thermal disinfection (Christopher and Pasquale, 2002;Whitney et al, 2003;Kowalski, 2006;Tseng and Li, 2006;Yu et al, 2008;Yoosook et al, 2009). Ozone is a strong oxidant with a tremendous ability to oxidize odors, organic compounds, microorganisms, and other substances (Franken, 2005).…”

“…Ozone is a strong oxidant with a tremendous ability to oxidize odors, organic compounds, microorganisms, and other substances (Franken, 2005). Due to its powerful oxidation potential, ozone has been applied in the disinfection of microorganisms in many fields, such as food, water, air, soil, and medicine (Franken, 2005;Takayama et al 2006;Tseng and Li, 2006;Naitou and Takahara, 2008;Uhm et al, 2009). Gaseous ozone is particularly effective in odor removal, is largely non-corrosive to equipment, has excellent disinfection capability, and provides complete coverage of all surfaces, making it ideal for application as an interior disinfectant (Franken, 2005).…”

Inactivation of Escherichia coli Cells in Aqueous Solution by Atmospheric-Pressure N 2 , He, Air, and O 2 Microplasmas

“…Due to the reactive species in plasma, gas-based reactive plasmas are thought to be effective in killing various microorganisms (1)(2)(3). Therefore, recently, the inactivation of microorganisms in water by atmospheric-pressure cold plasmas (APCP) has attracted great attention for biomedical and environmental applications due to their lethal effects on bacteria and fungi (4)(5)(6)(7)(8), since APCP include many reactive species similar to those in the conventional methods of microorganism inactivation, such as ozone generation (9), UV irradiation (10), chemical agents (11), electrical fields (12,13), and microwave irradiation (14).…”