Topical ozone therapy restores microbiome diversity in atopic dermatitis

•Short-term topical ozone therapy for AD can effectively alleviate disease conditions.•Topical ozone therapy can restore microbiome diversity in AD skin.•We demonstrate that Acinetobacter may be a potential probiotic. Staphylococcus aureus (S. aureus) accounts for 90% of the microbiome in atopic dermatitis (AD) lesions and plays a role in disease flare-ups and worsens disease outcome. Ozone treatment can improve AD conditions by its bactericidal effect on S. aureus. To study the effects of topical ozone therapy on microbiome diversity in AD lesions and explore potential probiotic pathogens correlated with AD progression. Patients with moderate to severe bilateral skin lesions in AD were recruited. Randomized split sides were performed. One side was treated with ozone hydrotherapy followed by ozonated oil; while the contralateral side with tap water and basal oil. Patients’ SCORAD scores and modified EASI were recorded before and after treatments. The microbiological compositions in targeting sites were determined using 16S rDNA sequencing. After three-day ozone therapy, patients showed a significant decrease in SCORAD scores and inflammatory cell infiltration in AD lesions. The micro-ecological diversity was higher in the non-lesional as compared with lesional areas (p