The coronavirus (COVID-19) pandemic induced by SARS-CoV-2 coronavirus remains a worldwide health problem for almost a year, where no end is in sight. There are several forms of COVID-19 infection with a variety of symptoms, with no clear predictors of disease outcome. Furthermore, clinical data imply the possibility of damage to various organs and tissues by COVID-19 infection manifesting several months after recovery. The pathogenesis of infection induced by SARS-CoV-2 still hides many unknowns and doubts, and the main conundrum is the patient's different immune response to infection. One of the possible factors contributing to outcome determination is oxidative stress, given that oxidative stress is one of the mechanisms of cell and tissue damage induced by coronaviruses such as influenza. Given that SARS-CoV-2 penetrates the cells via the ACE2 receptor, a highly represented protein in various cells and tissues in the body, COVID-19 infection can result in oxidative damage in a number of different organs and tissues.

The antioxidative defense system of the patient and oxidative damage by SARS-CoV-2 virus could be an important factor in the immune response to COVID-19 infection. The analysis of oxidative stress biomarkers and components of the antioxidative defense system in various forms of disease induced by COVID-19 infection, as well as in different section points during the disease could indicate the role of oxidative stress, as well as the need for timely intervention using various antioxidants. Correlations of oxidative stress with the immune response could provide insight into the interaction between the immune system and oxidative damage. Furthermore, the highlight of some causal relationship between the disturbance in the body redox balance, and components of the immune system could indicate the possibility of causal use of some immunomodulators, and cytokine antagonists combined with target antioxidative substances. Moreover, an important issue which could be answered is the rationality of antioxidant to prevent the occurrence of mild and severe COVID-19 infection.

The aim of this Special Issue is to solicit original research articles that highlight experimental and clinical results addressing the role of oxidative stress in the pathogenesis of COVID-19 infection. Submissions focussing on the modalities, and the effects of antioxidants as a therapeutic intervention in COVID-19 infection are also encouraged. In addition, authors are welcome to submit research containing novel data regarding the molecular mechanisms of oxidative damage in COVID-19 infection, and the possibility of antioxidative interventions as a therapeutic strategy for COVID-19 infection. Review articles discussing the state of the art are also welcome.

Potential topics include but are not limited to the following:

• Pathophysiology of COVID-19 infection
• Molecular mechanisms underlining the oxidative stress in COVID-19 infection
• Role of oxidative damage in the pathogenesis of COVID-19 infection
• Interplay between oxidative damage, and immune response in COVID-19 infection
• Activity of antioxidative defence system in prediction of outcome in COVID-19 infection
• Effects of antioxidant supplementation in COVID-19 infection
• Use of antioxidants to prevent COVID-19 infection
• Effects of antioxidant therapy in the severe forms of COVID-19 infection
• Age-dependent and gender-dependent changes in oxidative stress biomarkers in COVID-19
• Correlation between oxidative stress biomarkers, and other indicators of interest in COVID-19