From Therapeutic Hope to Environmental Foe
Once dismissed as alternative medicine, ozone therapy stepped into the pandemic spotlight, revealing a complex molecule with power to both heal and harm.
When the COVID-19 pandemic overwhelmed healthcare systems worldwide, doctors faced a devastating reality: no proven treatments existed for the severe pneumonia and inflammatory cascade the virus triggered. In this desperate climate, an old therapy with a controversial past—ozone treatment—experienced a dramatic resurgence. Meanwhile, environmental scientists were tracking a different ozone story unfolding outdoors, where air pollution was silently impacting agricultural survival. This is the story of ozone's dual role during the COVID era—a tale of medical innovation and environmental challenge that continues to shape our world today.
Ozone (O₃) is a gas composed of three oxygen atoms, best known for forming the protective layer in the Earth's stratosphere that shields us from harmful ultraviolet radiation. Yet at ground level, ozone becomes a harmful component of smog, damaging ecosystems and human health.
When the SARS-CoV-2 virus emerged, researchers noted that ozone's proposed mechanisms of action aligned perfectly with COVID-19's pathology. The virus causes extensive lung inflammation and microvascular thrombosis, leading to life-threatening hypoxia. Ozone therapy appeared to address multiple aspects of this cascade simultaneously1 .
Groundbreaking research published in Scientific Reports in 2021 unveiled exactly how ozone dismantles SARS-CoV-2. Using Atomic Force Microscopy and Transmission Electron Microscopy, scientists observed ozone's triple-action attack on the virus8 :
Ozone attacks the phospholipid bilayers of the viral envelope, creating holes that compromise the virus's structural integrity.
The virus's cysteine residues are oxidized, forming disulfide bonds that prevent proper viral replication.
Ozone causes the release of zinc ions from the virus's non-structural proteins, rendering them inactive.
This multifaceted attack made ozone particularly promising against SARS-CoV-2, especially when combined with its documented immunomodulatory effects. Ozone therapy stimulates interferon production, modulates inflammation, and improves oxygen delivery to tissues by increasing 2,3-diphosphoglycerate in red blood cells—addressing both the viral infection and its devastating complications1 6 .
As hospitals filled with patients experiencing severe respiratory failure, several medical centers began exploring ozone therapy as an adjunct treatment. The results, while mixed, offered glimpses of significant potential.
| Patient | Age | BMI | Baseline PaO₂/FiO₂ | Ozone Sessions | Outcome |
|---|---|---|---|---|---|
| Patient 1 | 49 | 31 | 235 | 6 over 3 days | Discharged day 4 |
| Patient 2 | 61 | 29 | 253 | 4 over 2 days | Discharged day 3 |
| Patient 3 | 64 | 20 | 243 | 6 total | Discharged day 4 |
| Outcome Measure | Effect of Ozone Therapy | Statistical Significance |
|---|---|---|
| Mortality Rate | Lower | P < 0.05 |
| Negative PCR Tests | 41% more patients | P < 0.05 |
| ICU Admissions | Lower (insignificant) | P > 0.05 |
| Hospital Stay | Shorter (insignificant) | P > 0.05 |
| LDH Serum Levels | Significant improvement | P < 0.05 |
A 2025 randomized controlled trial from Iran published in Frontiers of Medicine raised important safety concerns. This study of 60 severe COVID-19 patients found that those receiving ozone therapy had a 3.5-fold increased probability of mortality and a 4.3-times higher odds of ICU transfer, though these results didn't reach statistical significance in their limited sample3 .
This conflicting evidence illustrates the complex nature of medical ozone—its efficacy appears highly dependent on patient selection, ozone concentration, administration method, and treatment timing.
The therapeutic use of ozone represented only one facet of its COVID-era application. With personal protective equipment shortages plaguing healthcare systems worldwide, ozone emerged as a powerful tool for decontaminating difficult-to-clean surfaces and equipment.
Research demonstrated that ozone effectively eliminated SARS-CoV-2 RNA from various materials7 . The optimal conditions varied by context:
| Surface Type | Ozone Concentration | Exposure Time | Efficacy |
|---|---|---|---|
| Face Masks & PPE | 90 ppm | 120 minutes | Virus eliminated |
| Office Supplies | 4000 ppm | 10 minutes | Virus eliminated |
| CPAP Tubes | 10,000 ppm | 10 minutes | Virus eliminated |
| Lab Equipment | 90 ppm | 120 minutes | Virus eliminated |
This application allowed healthcare facilities to safely extend the life of precious protective equipment during critical shortages. Design studios even created open-source UV-C decontamination toolkits using ozone principles, shipping units to hospitals in Uganda as part of pilot programs5 .
While medical researchers explored ozone's therapeutic potential, environmental scientists documented a different COVID-era ozone story. As reported in 2025, research from Zhejiang A&F University and Boston College revealed how rising surface ozone pollution threatened food security in China2 .
This research highlighted the delicate balance between industrial activity and environmental health—while pandemic restrictions devastated economies, they offered temporary relief from the relentless increase in ozone pollution that threatens global food systems.
The investigation of ozone's potential against COVID-19 required specialized equipment and methodologies. Key research components included:
The COVID-19 pandemic forced a reexamination of many therapeutic approaches, including ozone therapy. While definitive conclusions about its medical efficacy remain elusive, the evidence suggests ozone may find a place as an adjunct therapy for viral infections and inflammatory conditions, particularly when conventional treatments are limited.
The environmental findings remind us that despite its potential medical benefits, ground-level ozone pollution remains a serious threat to ecosystem stability and food security. This duality captures the essence of ozone in the COVID era—a molecule of paradoxes, capable of both destruction and healing.
As research continues, the lessons learned from ozone's pandemic journey will undoubtedly influence how we approach future health crises, environmental challenges, and the complex interplay between human activity and the natural world.
This article synthesizes findings from clinical case reports, randomized controlled trials, meta-analyses, and environmental studies to present a comprehensive picture of ozone's role during the COVID-19 pandemic.