Treatment with Ozone significantly decreased mortality, polymerase chain reaction (PCR) positivity, and duration of stay in hospital in COVID-19 patients, according to a systematic review and meta-analysis. The purpose of this study was to evaluate the effectiveness of Ozone on COVID-19 patient mortality.

Without language restrictions, databases such as clinicaltrials.gov, Embase, Cochrane Library, and PubMed were explored for relevant literature search. A review was conducted on prospective controlled studies comparing Ozone therapy for COVID-19 to placebo or blank. With 95% confidence intervals (CIs), studies were pooled to weighted mean differences (WMDs) and risk ratios (RRs).

The inclusion criteria were satisfied by eight studies (n = 371). Significant effects of Ozone treatment were shown for PCR positivity (RR 0.07), hospital stay duration (WMD -1.63 days), and mortality (RR 0.38). Thus, Ozone treatment should be taken into account for COVID-19 patients.