Ozone potential to fight against SAR-COV-2 pandemic: facts and research needs

Abstract

The greatest challenge the world is facing today is to win the battle against COVID-19 pandemic as soon as possible. Until a vaccine is available, personal protection, social distancing, and disinfection are the main tools against SARS-CoV-2. Although it is quite infectious, the SARS-CoV-2 virus itself is an enveloped virus that is relatively fragile because its protective fatty layer is sensitive to heat, ultraviolet radiation, and certain chemicals. However, heat and liquid treatments can damage some materials, and ultraviolet light is not efficient in shaded areas, so other disinfection alternatives are required to allow safe re-utilization of materials and spaces. As of this writing, evidences are still accumulating for the use of ozone gas as a disinfectant for sanitary materials and ambient disinfection in indoor areas. This paper reviews the most relevant results of virus disinfection by the application of gaseous ozone. The review covers disinfection treatments of both air and surfaces carried out in different volumes, which varies from small boxes and controlled chambers to larger rooms, as a base to develop future ozone protocols against COVID-19. Published papers have been critically analyzed to evaluate trends in the required ozone dosages, as a function of relative humidity (RH), contact time, and viral strains. The data have been classified depending on the disinfection objective and the volume and type of the experimental set-up. Based on these data, conservative dosages and times to inactivate the SARS-CoV-2 are estimated. In small chambers, 10–20 mg ozone/m3 over 10 to 50 min can be sufficient to significantly reduce the virus load of personal protection equipment. In large rooms, 30 to 50 mg ozone/m3 would be required for treatments of 20–30 min. Maximum antiviral activity of ozone is achieved at high humidity, while the same ozone concentrations under low RH could result inefficient. At these ozone levels, safety protocols must be strictly followed. These data can be used for reducing significantly the viral load although for assuring a safe disinfection, the effective dosages under different conditions need to be confirmed with experimental data.

Potent Activity of High Concentration Ozone Therapy Against Antibiotic-Resistant Bacteria

“…Although few studies have investigated the relationship between ozone concentration and the microclimate conditions of different environments [88], some experiments have demonstrated that ozone concentration and relative humidity values played an important role in ozone efficiency and antimicrobial effect [89]. Humidity is an important parameter and must be considered because, in arid environmental conditions, the disinfection procedure may require a considerably longer exposure time.…”

<p>Efek paparan gas ozon terhadap mikroba saliva rongga mulut secara in-vitro<p></p>Effects of ozone gas exposure on oral saliva microbes in-vitro<p>

“…5,11 Ozon membunuh mikroba dalam waktu yang singkat dengan cara merusak dinding sel. 12,13 Ozon dengan konsentrasi 10 ppm efisien untuk membunuh virus dalam waktu 10 menit dalam ruangan kecil. 14 Penggunaan ozon dalam prosedur asepsis di klinik gigi khususnya di Indonesia, belum banyak dilakukan, mengingat ketersediaan alat penghasil gas ozon.…”

“…20 Mikroba jamur mempunyai struktur polisakarida, lipid dan protein rantai panjang, lebih resisten terhadap efek oksidasi dari ozon. 13,27 Resistensi mikroba terhadap ozon diduga juga berhubungan dengan umur koloni.…”

SARS-CoV2 neutralizing activity of ozone on porous and non-porous materials

“…Moreover, the virus-inactivating activity of ozone was demonstrated for different metals, contaminated with a corona pseudovirus and HuCoV-229E, such as stainless steel, nickel and copper as well as glass [ 19 ]. Since ozone dosages for disinfection of different surfaces vary, a process is needed that is suitable for hard materials and PPE [ 20 , 21 ].…”